Matt Williams is a space journalist and science communicator for Universe Today and Interesting Engineering. He's also a science fiction author, podcaster (Stories from Space), and Taekwon-Do instructor who lives on Vancouver Island with his wife and family.
For the remainder of 2016, all payloads traveling to the US National Lab aboard the ISS will feature a mission patch with Marvel characters. Credit: NASA
In 2011, the US government created the Center for the Advancement of Science in Space (CASIS) to manage the US National Laboratory aboard the International Space Station,. With the purpose of ensuring that research opportunities provided by the ISS are used to their full potential, CASIS also seeks to inspire new generations of students to become involved in STEMs research and space exploration.
With the next generation in mind, CASIS recently announced the creation of a new mission patch that is sure to appeal to sci-fi fans and space enthusiasts! The patch features Groot and Rocket Raccoon, two characters from the Guardians of the Galaxy franchise, and was designed by Marvel Comic’s Custom Solution Group. For the remainder of 2016, it will represent all payloads that are destined for the ISS’ US National Laboratory.
The announcement came at the 2016 San Diego Comic Con, where tens of thousands of fans were gathered to witness the latest from their favorite sci-fi, fantasy, and comic book franchises. In between all the trailers and fanfare, members of CASIS held a panel discussion to talk about their collaboration with Marvel, and explained why it was these two Guardians characters that were selected to promote activities aboard the ISS.
This mission patch, featuring Groot and Rocket Racoon, will adorn all cargo going to CASIS labs in 2016. Credit: iss-casis.org
As Patrick O’Neill, a representative of CASIS, was quoted by The Verge as saying: “These are characters who have a bit of a space-based background to begin with. So both of [these] characters already embody some of the characteristics associated with what’s happening on the space station.”
The patch – which was designed by famed Marvel artist “Juan Doe” – features Groot and Rocket Racoon staring up at the ISS, which is floating overhead. In and around them, stars that are made to look like the flames from the Guardian of the Galaxy shield are positioned. In addition to being artistically creative, the symbolism could not be more clear: pop-culture icons and the ISS National Lab coming together to raise awareness about important scientific research!
During 2016, the U.S. National Lab plans to conduct over 100 science investigations aboard the ISS, with experiments involving the physical and material sciences, technological development, Earth observation and student inquiries. Thanks to its partnership with Marvel, the Guardians-inspired patch will adorn every payload that is sent to the ISS as part of these research initiatives.
Obviously, this partnership has been a good way for Marvel to promote one of the latest installments in its cinematic universe (not to mention its upcoming sequel). But for CASIS, it was also an opportunity to draw attention to the work of the U.S. National Lab. Traditionally, CASIS is responsible for providing seed money to research projects and product development. But a major aspect of their work also includes providing expertise, access, support, and educational outreach.
The Center for the Advancement of Science in Space (CASIS), shown here as part of the ISS. Credit: iss-casis.org
As Ken Shields, the CASIS Director of Operations and Educational Opportunities, said in a CASIS press release:
“A major mission for us here at CASIS is to find unique and innovative ways to bring notoriety to the ISS National Laboratory and the research that is being conducted on our orbiting laboratory. There are very few brands in the world who have as large an impact as Marvel, and we are thrilled to partner with them on this project and look forward to Rocket and Groot inspiring a new generation of researchers interested in the space station.”
Later this year, CASIS also hopes to use these characters in an upcoming educational flight contest intended to inspire children to become the next generation of scientists and engineers. News of the mission patch also came amidst announcements that Rocket and Groot will be star in their own Rocket Raccoon and Groot comic, and will be returning to the big screen next summer for Guardians of the Galaxy 2.
Obviously, this is going to be a good year for a certain tree alien and hyper-raccoon! And be sure to check out this video of the creation of the new mission patch, courtesy of CASIS:
The Saturn V (left) and the Falcon Heavy (right). Credit: NASA/SpaceX
Its an Epic Rocket Battle! Or a Clash of the Titans, if you will. Except that in this case, the titans are the two of the heaviest rockets the world has ever seen. And the contenders couldn’t be better matched. On one side, we have the heaviest rocket to come out of the US during the Space Race, and the one that delivered the Apollo astronauts to the Moon. On the other, we have the heaviest rocket created by the NewSpace industry, and which promises to deliver astronauts to Mars.
And in many respects, the Falcon Heavy is considered to be the successor of the Saturn V. Ever since the latter was retired in 1973, the United States has effectively been without a super-heavy lifter. And with the Space Launch System still in development, the Falcon Heavy is likely to become the workhorse of both private space corporations and space agencies in the coming years.
So let’s compare these two rockets, taking into account their capabilities, specifications, and the history of their development and see who comes out on top. BEGIN!
Launch of the modified Saturn V rocket carrying the Skylab space station. Credit: NASA
Development History:
The development of the Saturn V began in 1946 with Operation Paperclip, a US government program which led to the recruitment of Wernher von Braun and several other World War II-era German rocket scientists and technicians. The purpose of this program was to leverage the expertise of these scientists to give the US an edge in the Cold War through the development of intercontinental ballistic missiles (ICBMs).
Between 1945 and the mid-to-late 50s von Braun acted as an advisor to US armed forces for the sake of developing military rockets only. It was not until 1957, with the Soviet launch of Sputnik-1 using an R-7 rocket – a Soviet ICBM also capable of delivering thermonuclear warheads – that the US government began to consider the use of rockets for space exploration.
Thereafter, von Braun and his team began developing the Jupiter series of rockets – a modified Redstone ballistic missile with two solid-propellant upper stages. These proved to be a major step towards the Saturn V, hence why the Jupiter series was later nicknamed “an infant Saturn”. Between 1960 and 1962, the Marshall Space Flight Center began designing the rockets that would eventually be used by the Apollo Program.
After several iterations, the Saturn C-5 design (later named the Saturn V) was created. By 1964, it was selected for NASA’s Apollo Program as the rocket that would conduct a Lunar Orbit Rendezvous (LRO). This plan called for a large rocket to launch a single spacecraft to the Moon, but only a small part of that spacecraft (the Lunar Module) would actually land on the surface. That smaller module would then rendezvous with the main spacecraft – the Command/Service Module (CSM) – in lunar orbit and the crew would return home.
A Saturn V launching the historic Apollo 11 mission. Credit: NASA/Michael Vuijlsteke. Public Domain image.
Development of the Falcon Heavy was first announced in 2011 at the National Press Club in Washington D.C. In a statement, Musk drew direct comparisons to the Saturn V, claiming that the Falcon Heavy would deliver “more payload to orbit or escape velocity than any vehicle in history, apart from the Saturn V moon rocket, which was decommissioned after the Apollo program.”
Consistent with this promise of a “super heavy-lift” vehicle, SpaceX’s original specifications indicated a projected payload of 53,000 kg (117,000 lbs) to Low-Earth Orbit (LEO), and 12,000 kgg (26,000 lbs) to Geosynchronous Transfer Orbit (GTO). In 2013, these estimates were revised to 54,400 kg (119,900 lb) to LEO and 22,200 kg (48,900 lb) to GTO, as well as 16,000 kilograms (35,000 lb) to translunar trajectory, and 13,600 kilograms (31,000 lb) on a trans-Martian orbit to Mars, and 2,900 kg (6,400 lb) to Pluto.
In 2015, the design was changed – alongside changes to the Falcon 9 v.1.1 – to take advantage of the new Merlin 1D engine and changes to the propellant tanks. The original timetable, proposed in 2011, put the rocket’s arrival at SpaceX’s west-coast launch location – Vandenberg Air Force Base in California – at before the end of 2012.
The first launch from Vandenberg was take place in 2013, while the first launch from Cape Canaveral was to take place in late 2013 or 2014. But by mid-2015, delays caused by failures with Falcon 9 test flights caused the first launch to be pushed to late 2016. The rocket has also been relocated to the Kennedy Space Center Launch Complex in Florida.
Artist’s concept of the SpaceX Red Dragon spacecraft launching to Mars on SpaceX Falcon Heavy as soon as 2018. Credit: SpaceX
SpaceX also announced in July 0f 2016 that it planned to expand its landing facility near Cape Canaveral to take advantage of the reusable technology. With three landing pads now planned (instead of one on land and a drone barge at sea), they hope to be able to recover all of the spent boosters that will be used for the launch of a Falcon Heavy.
Design:
Both the Saturn V and Falcon Heavy were created to do some serious heavy lifting. Little wonder, since both were created for the sole purpose of “slipping the surly bonds” of Earth and putting human beings and cargo onto other celestial bodies. For its part, the Saturn V‘s size and payload surpassed all other previous rockets, reflecting its purpose of sending astronauts to the Moon.
With the Apollo spacecraft on top, it stood 111 meters (363 feet) tall and was 10 meters (33 feet) in diameter, without fins. Fully fueled, the Saturn V weighed 2,950 metric tons (6.5 million pounds), and had a payload capacity estimated at 118,000 kg (261,000 lbs) to LEO, but was designed for the purpose of sending 41,000 kg (90,000 lbs) to Trans Lunar Insertion (TLI).
Later upgrades on the final three missions boosted that capacity to 140,000 kg (310,000 lbs) to LEO and 48,600 kg (107,100 lbs) to the Moon. The Saturn V was principally designed by NASA’s Marshall Space Flight Center in Huntsville, Alabama, while numerous subsystems were developed by subcontractors. This included the engines, which were designed by Rocketdyne, a Los Angeles-based rocket company.
Diagram of Saturn V Launch Vehicle. Credit: NASA/MSFC
The first stage (aka. S-IC) measured 42 m (138 feet) tall and 10 m (33 feet) in diameter, and had a dry weight of 131 metric tons (289,000 lbs) and a total weight of over 2300 metric tons (5.1 million lbs) when fully fueled. It was powered by five Rocketdyne F-1 engines arrayed in a quincunx (four units arranged in a square, and the fifth in the center) which provided it with 34,000 kN (7.6 million pounds-force) of thrust.
The Saturn V consisted of three stages – the S-IC first stage, S-II second stage and the S-IVB third stage – and the instrument unit. The first stage used Rocket Propellant-1 (RP-1), a form of kerosene similar to jet fuel, while the second and third stages relied on liquid hydrogen for fuel. The second and third stage also used solid-propellant rockets to separate during launch.
The Falcon Heavy is based around a core that is a single Falcon 9 with two additional Falcon 9 first stages acting as boosters. While similar in concept to the Delta IV Heavy launcher and proposals for the Atlas V HLV and Russian Angara A5V, the Falcon Heavy was specifically designed to exceed all current designs in terms of operational flexibility and payload. As with other SpaceX rockets, it was also designed to incorporate reusability.
The rocket relies on two stages, with the possibility of more to come, that measure 70 m (229.6 ft) in height and 12.2 m (39.9 ft) in width. The first stage is powered by three Falcon 9 cores, each of which is equipped with nine Merlin 1D engines. These are arranged in a circular fashion with eight around the outside and one in th middle (what SpaceX refers to as the Octaweb) in order to streamline the manufacturing process. Each core also includes four extensible landing legs and grid fins to control descent and conduct landings.
Chart comparing SpaceX’s Falcon 9 and Falcon Heavy rocket. Credit: SpaceX
The first stage of the Falcon Heavy relies on Subcooled LOX (liquid oxygen) and chilled RP-1 fuel; while the upper stage also uses them, but under normal conditions. The Falcon Heavy has a total sea-level thrust at liftoff of 22,819 kN (5,130,000 lbf) which rises to 24,681 kN (5,549,000 lbf) as the craft climbs out of the atmosphere. The upper stage is powered by a single Merlin 1D engine which has a thrust of 34 kN (210,000 lbf) and has been modified for use in a vacuum.
Although not a part of the initial Falcon Heavy design, SpaceX has been extending its work with reusable rocket systems to ensure that the boosters and core stage can be recovered. Currently, no work has been announced on making the upper stages recoverable as well, but recent successes recovering the first stages of the Falcon 9 may indicate a possible change down the road.
The consequence of adding reusable technology will mean that the Falcon Heavy will have a reduced payload to GTO. However, it will also mean that it will be able to fly at a much lower cost per launch. With full reusability on all three booster cores, the GTO payload will be approximately 7,000 kg (15,000 lb). If only the two outside cores are reusable while the center is expendable, the GTO payload would be approximately 14,000 kg (31,000 lb).
Cost:
The Saturn V rocket was by no means a small investment. In fact, one of the main reasons for the cancellation of the last three Apollo flights was the sheer cost of producing the rockets and financing the launches. Between 1964 and 1973, a grand total of $6.417 billion USD was appropriated for the sake of research, development, and flights.
A Saturn V rocket viewed from the rear, showing its five Rocketdyne F-1 engines. Credit: Infinity Science Center
Adjusted to 2016 dollars, that works out to $41.4 billion USD. In terms of individual launches, the Saturn V would cost between $185 and $189 million USD, of which $110 million was spent on production alone. Adjusted for inflation, this works out to approximately $1.23 billion per launch, of which $710 million went towards production.
By contrast, when Musk appeared before the US Senate Committee on Commerce, Science and Transportation in May 2004, he stated that his ultimate goal with the development of SpaceX was to bring the total cost per launch down to $1,100 per kg ($500/pound). As of April 2016, SpaceX has indicated that a Falcon Heavy could lift 2268 kg (8000 lbs) to GTO for a cost of $90 million a launch – which works out to $3968.25 per kg ($1125 per pound).
No estimates are available yet on how a fully-reusable Falcon Heavy will further reduce the cost of individual launches. And again, it will vary depending on whether or not the boosters and the core, or just the external boosters are recoverable. Making the upper stage recoverable as well will lead to a further drop in costs, but will also likely impact performance.
Specifications:
So having covered their backgrounds, designs and overall cost, let’s move on to a side-by-side comparison of these two bad boys. Let’s see how they stack up, pound for pound, when all things are considered – including height, weight, lift payload, and thrust.
Saturn V:
Falcon Heavy:
Height:
110.6 m (363 ft)
70 m (230 ft)
Diameter:
10.1 m (33 ft)
12.2 m (40 ft)
Weight:
2,970,000 kg
(6,540,000 lbs)
1,420,788 kg
(3,132,301 lb)
Stages:
3
2+
Engines
(1st Stage):
5 Rocketdyne F-1
3 x 9 Merlin 1D
2nd stage
5 Rocketdyne J-2
1 Merlin 1D
3rd stage
1 Rocketdyne J-2
Thrust
(1st stage):
34,020 kN
22,918 kN (sea level);
24,681 kN (vacuum)
2nd stage
4,400 kN
934 kN
3rd stage
1,000 kN
Payload (LEO):
140,000 kg
(310,000 lbs)
54,400 kg
(119,900 lbs)
Payload (TLI):
48,600 kg
(107,100 lbs)
16,000 kg
(35,000 lbs)
When put next to each other, you can see that the Saturn V has the advantage when it comes to muscle. It’s bigger, heavier, and can deliver a bigger payload to space. On the other hand, the Falcon Heavy is smaller, lighter, and a lot cheaper. Whereas the Saturn V can put a heavier payload into orbit, or send it on to another celestial body, the Falcon Heavy could perform several missions for every one mounted by its competitor.
But whereas the contributions of the venerable Saturn V cannot be denied, the Falcon Heavy has yet to demonstrate its true worth to space exploration. In many ways, its like comparing a retired champion to an up-and-comer who, despite showing lots of promise and getting all the headlines, has yet to win a single bout.
But should the Falcon Heavy prove successful, it will likely be recognized as the natural successor to the Saturn V. Ever since the latter was retired in 1973, NASA has been without a rocket with which to mount long-range crewed missions. And while heavy-lift options have been available – such as the Delta IV Heavy and Atlas V – none have had the performance, payload capacity, or the affordability that the new era of space exploration needs.
In truth, this battle will take several years to unfold. Only after the Falcon Heavy is rigorously tested and SpaceX manages to deliver on their promises of cheaper space launches, a return to the Moon and a mission to Mars (or fail to, for that matter) will we be able to say for sure which rocket was the true champion of human space exploration! But in the meantime, I’m sure there’s plenty of smack talk to be had by fans of both! Preferably in a format that rhymes!
For decades, Canada has made significant contributions to the field of space exploration. These include the development of sophisticated robotics, optics, participation in important research, and sending astronauts into space as part of NASA missions. And who can forget Chris Hadfield, Mr. “Space Oddity” himself? In addition to being the first Canadian to command the ISS, he is also known worldwide as the man who made space exploration fun and accessible through social media.
And in recent statement, the Canadian Space Agency (CSA) has announced that it is looking for new recruits to become the next generation of Canadian astronauts. With two positions available, they are looking for applicants who embody the best qualities of astronauts, which includes a background in science and technology, exceptional physical fitness, and a desire to advance the cause of space exploration.
Over the course of the past few decades, the Canadian Space Agency has established a reputation for the development of space-related technologies. In 1962, Canada deployed the Alouette satellite, which made it the third nation – after the US and USSR – to design and build its own artificial Earth satellite. And in 1972, Canada became the first country to deploy a domestic communications satellite, known as Anik 1 A1.
The “Canadarm”, pictured here as part of Space Shuttle mission STS-2, it’s first deployment to space, in November of 1981. Credit: NASA
Perhaps the best-known example of Canada’s achievements comes in the field of robotics, and goes by the name of the Shuttle Remote Manipulator System (aka. “the Canadarm“). This robotic arm was introduced in 1981, and quickly became a regular feature within the Space Shuttle Program.
“Canadarm is the best-known example of the key role of Canada’s space exploration program,” said Maya Eyssen, a spokeperson for the CSA, via email. “Our robotic contribution to the shuttle program secured a mission spot for our nation’s first astronaut to fly to space –Marc Garneau. It also paved the way for Canada’s participation in the International Space Station.”
It’s successor, the Canadarm2, was mounted on the International Space Station in 2001, and has since been augmented with the addition of the Dextre robotic hand – also of Canadian design and manufacture. This arm, like its predecessor, has become a mainstay of operations aboard the ISS.
“Over the past 15 years, Canadarm2 has played a critical role in assembling and maintaining the Station,” said Eyssen. “It was used on almost every Station assembly mission. Canadarm2 and Dextre are used to capture commercial space ships, unload their cargo and operate with millimeter precision in space. They are both featured on our $5 bank notes. The technology behind these robots also benefits those on earth through technological spin-offs used for neurosurgery, pediatric surgery and breast-cancer detection.”
Canada’s Dextre robotic “handyman” and Canadarm2 pictured digging out the trunk of a SpaceX’s Dragon cargo vessel docked to the ISS. Credit: NASA
In terms of optics, the CSA is renowned for the creation of the Advanced Space Vision System (SVS) used aboard the ISS. This computer-vision system uses regular 2D cameras located in the Space Shuttle Bay, on the Canadarm, or on the hull of the ISS itself – along with cooperative targets – to calculate the 3D position of objects around of the station.
But arguably, Canada’s most enduring contribution to space exploration have come in the form of its astronauts. Long before Hadfield was garnering attention with his rousing rendition of David Bowie’s “Space Oddity“, or performing “Is Someone Singing (ISS)” with The Barenaked Ladies and The Wexford Gleeks choir (via a video connection from the ISS), Canadians were venturing into space as part of several NASA missions.
Consider Marc Garneau, a retired military officer and engineer who became the first Canadian astronaut to go into space, taking part in three flights aboard NASA Space shuttles in 1984, 1996 and 2000. Garneau also served as the president of the Canadian Space Agency from 2001 to 2006 before retiring for active service and beginning a career in politics.
And how about Roberta Bondar? As Canada’s first female astronaut, she had the additional honor of designated as the Payload Specialist for the first International Microgravity Laboratory Mission (IML-1) in 1992. Bondar also flew on the NASA Space Shuttle Discovery during Mission STS-42 in 1992, during which she performed experiments in the Spacelab.
The Soyuz TMA-15 crew (from left to right), showing Robert Thirsk, Roman Romanenko, and Frank De Winne. Credit: NASA/Victor Zelentsov
And then there’s Robert Thirsk, an engineer and physician who holds the Canadian records for the longest space flight (187 days 20 hours) and the most time spent in space (204 days 18 hours). All three individuals embodied the unique combination of academic proficiency, advanced training, personal achievement, and dedication that make up an astronaut.
And just like Hadfield, Bonard, Garneau and Thirsk have all retired on gone on to have distinguished careers as chancellors of academic institutions, politicians, philanthropists, noted authors and keynote speakers. All told, eight Canadians astronauts have taken part in sixteen space missions and been deeply involved in research and experiments conducted aboard the ISS.
Alas, every generation has to retire sooner or later. And having made their contributions and moved onto other paths, the CSA is looking for two particularly bright, young, highly-motivated and highly-skilled people to step up and take their place.
The recruitment campaign was announced this past Sunday, July 17th, by the Honourable Navdeep Bains – the Minister of Innovation, Science and Economic Development. Those who are selected will be based at NASA’s Johnson Space Center in Houston, Texas, where they will provide support for space missions in progress, and prepare for future missions.
Canadian astronaut Chris Hadfield, the first Canadian to serve as commander of the ISS. Credit: CTV
Canadian astronauts also periodically return to Canada to participate in various activities and encourage young Canadians to pursue an education in the STEM fields (science, technology, engineering and mathematics). As Eyssen explained, the goals of the recruitment drive is to maintain the best traditions of the Canadian space program as we move into the 21st century:
“The recruitment of new astronauts will allow Canada to maintain a robust astronaut corps and be ready to play a meaningful role in future human exploration initiatives. Canada is currently entitled to two long-duration astronaut flights to the ISS between now and 2024. The first one, scheduled for November 2018, will see David Saint-Jacqueslaunch to space for a six-month mission aboard the ISS. The second flight will launch before 2024. As nations work together to chart the next major international space exploration missions, our continued role in the ISS will ensure that Canada is well-positioned to be a trusted partner in humanity’s next steps in space.
“Canada is seeking astronauts to advance critical science and research aboard the International Space Station and pave the way for human missions beyond the Station. Our international partners are exploring options beyond the ISS. This new generation of astronauts will be part of Canada’s next chapter of space exploration. That may include future deep-space exploration missions.”
The recruitment drive will be open from June 17th to August 15th, 2016, and the selected candidates are expected to be announced by next summer. This next class of Canadian astronaut candidates will start their training in August 2017 at the Johnson Space Center. The details can be found at the Canadian Space Agency‘s website, and all potential applicants are advised to read the campaign information kit before applying.
Alongside their efforts to find the next generation of astronauts, the Canadian government’s 2016 annual budget has also provided the CSA with up to $379 million dollars over the next eight years to extend Canada’s participation in the International Space Station on through to 2024. Gotta’ keep reaching for those stars, eh?
The Falcon Heavy, once operational, will be the most powerful rocket in the world. Credit: SpaceX
Since 2000, Elon Musk been moving forward with his vision of a fleet of reusable rockets, ones that will restore domestic launch capability to the US and drastically reduce the cost of space launches. The largest rocket in this fleet is the Falcon Heavy, a variant of the Falcon 9 that uses the same rocket core, with two additional boosters that derived from the Falcon 9 first stage. When it lifts off later this year, it will be the most operational powerful rocket in the world.
More than that, SpaceX intends to make all three components of the rocket fully recoverable. This in turn will mean mean that the company is going to need some additional landing pads to recover them all. As such, the company recently announced that it is seeking federal permission to create second and third landing zones for their incoming rockets on Florida’s Space Coast.
The announcement came on Monday, July 18th, during a press conference at their facility at the Cape Canaveral Air Force Station. As they were quoted as saying by the Orlando Sentinel:
“SpaceX expects to fly Falcon Heavy for the first time later this year. We are also seeking regulatory approval to build two additional landing pads at Cape Canaveral Air Force Station. We hope to recover all three Falcon Heavy rockets, though initially we may attempt drone ship landings [at sea].”
Artist’s concept of the SpaceX Falcon Heavy launching in 2018. Credit: SpaceX
At present, SpaceX relies on both drone ships and their landing site at Cape Canaveral to recover rocket boosters after they return to Earth. Which option they have used depended on how high and how far downrange the rockets traveled. But with this latest announcement, they are seeking to recover all three boosters used in a single Falcon Heavy launch, which could prove to be essential down the road.
Since December, SpaceX has managed to successfully recover five Falcon 9 rockets, both at sea and on land. In fact, the announcement of their intentions to expand their landing facilities on Monday came shortly after a spent Falcon 9 returned to the company’s landing site, shortly after deploying over 2268 kg (5000 lbs) of cargo into space during a nighttime launch.
But the planned launch of the Falcon Heavy – Falcon Heavy Demo Flight 1, which is scheduled to take place this coming December – is expected to break new ground. For one, it will give the private aerospace company the ability to lift over 54 metric tons (119,000 lbs) into orbit, more the twice the payload of a Delta IV Heavy – the highest capacity rocket in service at the moment.
Chart comparing SpaceX’s Falcon 9 and Falcon Heavy. Credit: SpaceX
Foremost among these are Elon Musk’s plans to colonize Mars. These efforts will begin in April or May of 2018 with the launch of the Dragon 2capsule (known as the “Red Dragon”) using a Falcon Heavy. As part of an agreement with NASA to gain more information on Mars landings, the Red Dragon will send a payload to Mars that has yet to be specified.
Beyond that, the details are a bit sketchy; but Musk has indicated that he is committed to mounting a crewed mission to Mars by 2024. And if all goes well with Demo Flight 1, SpaceX expects to follow it up with Falcon Heavy Demo Flight 2 in March of 2017. This launch will see the Falcon Heavy being tested as part of the U.S. Air Force’s Evolved Expendable Launch Vehicle (EELV) certification process.
The rocket will also be carrying some important payloads, such as The Planetary Society’s LightSail 2. This 32 square-meter (344 square-foot) craft, which consists of four ultra-thin Mylar sails, will pick up where its predecessor (the LightSail 1, which was deployed in June 2015) left off – demonstrating the viability of solar sail spacecraft.
Apollo 11’s Saturn V rocket prior to the launch July 16, 1969. Screenshot from the 1970 documentary “Moonwalk One.” Credit: NASA/Theo Kamecke/YouTube
The Falcon Heavy boasts three Falcon 9 engine cores, each of which is made up of 9 Merlin rocket engines. Together, these engines generate more than 2.27 million kg (5 million pounds) of thrust at liftoff, which is the equivalent of approximately eighteen 747 aircraft. Its lift capacity is also equivalent to the weight of a fully loaded 737 jetliner, complete with passengers, crew, luggage and fuel.
The Saturn V rocket – the workhorse of the Apollo Program, and which made its last flight in 1973 – is only American rocket able to deliver more payload into orbit. This is not surprising, seeing as how the Falcon Heavy was specifically designed for a new era of space exploration, one that will see humans return to the Moon, go to Mars, and eventually explore the outer Solar System.
Fingers crossed that everything works out and the Falcon Heavy proves equal to the enterprise. The year of 2024 is coming fast and many of us are eager to see boots being put to red soil! And be sure to enjoy this animation of the Falcon Heavy in flight:
The planet Venus, as imaged by the Magellan 10 mission. The planet's inhospitable surface makes exploration extremely difficult. Credit: NASA/JPL
Venus is often refereed to as “Earth’s sister planet”, thanks to the number of things it has in common with our planet. As a terrestrial planet, it is similarly composed of silicate rock and metals – which are differentiated between a metal core and a silicate crust and mantle. It also orbits within our Sun’s habitable zone, and had a similarly violent volcanic past.
But of course, there are also some major differences between our two planets. For one, Venus has an atmosphere that is incredibly dense (92 times that of Earth, in fact) and reaches temperatures that are hot enough to melt lead. In addition, the planet’s rotation is immensely slow by comparison, taking 243.025 days to complete a single rotation, and rotating backwards relative to Earth.
When discussing Venus’ rotation, it is important to note certain distinctions. Rotation is the time it takes for a planet to spin once on its axis. This is different from a planet’s revolution, which is the time it takes for a planet to orbit around another object (i.e. the Sun). So while it takes the Earth one day (24 hours) to rotate once on its axis, it takes one year (365.256 days) to revolve once around the Sun.
Earth and Venus’ orbit compared. Credit: Sky and Telescope
Orbital Period:
In Venus’ case, things work a little differently. For starters, it orbits the Sun at an average distance of about 0.72 AU (108,000,000 km; 67,000,000 mi) with almost no eccentricity. In fact, with its farthest orbit (aphelion) of 0.728 AU (108,939,000 km) and closest orbit (perihelion) of 0.718 AU (107,477,000 km), it has the most circular orbit of any planet in the Solar System.
The planet completes a revolution around the Sun every 224.65 Earth days, which means that a year on Venus last about 61.5% as long as a year on Earth. Evey 584 days, Venus completes an interior conjunction, where it lies between Earth and the Sun. It is at this point that Venus makes the closest approach to Earth of any planet, at an average distance of 41 million km.
Rotational Period:
Unlike most other planets in the Solar System, which rotate on their axes in an counter-clockwise direction, Venus rotates clockwise (called “retrograde” rotation). It also rotates very slowly, taking 243.025 Earth days to complete a single rotation. This is not only the slowest rotation period of any planet, it also means that a single day on Venus lasts longer than a Venusian year.
Phases of Venus during 2004 photographed through a telescope. When very close to inferior conjunction (bottom right) the crescent is seen to extend fully around the planet. Credit: Statis Kalyva / Wikipedia
And, as noted earlier, Venus’ rotation is backwards, relative to Earth and the other bodies in the Solar System. Technically, this means that its rotational period is -243,025 days. It also means that if you could view the Solar System from the position above its celestial north pole, all of the planets (except for Uranus, which rotates on its side!) would appear to be rotating clockwise.
Venus, however, would appear to be rotating in a clockwise direction. Because of this, if you could stand on the surface of Venus, you would witness the Sun rising in the west and setting in the east. But you would be waiting a very long time to see this happen! Read on to find out why…
Sidereal vs. Solar Day:.
Another important thing to consider is the difference between a sidereal day and a solar day. A sidereal day corresponds to the amount of time it takes for a planet to rotate once on its axis, which in Venus’ case takes 243.025 Earth days. A solar day, by contrast, refers to the amount of time it takes for the Sun to reappear at the same point in the sky (i.e. between one sunrise/sunset and the next).
A Venusian (aka. Cytherean) Solar Day is the equivalent to 116.75 days on Earth, which means that it takes almost 117 days for the sun to rise, set, and return to the same place in the sky. Doing the math, we then see that a single year on Venus (224.65 Earth days) works out to just 1.92 Venusian (solar) days. Not exactly the basis for a good calendar system, is it?
View of Venus from the Solar Dynamics Observatory. If viewed from the surface of Venus, the Sun would be moving from west to east in the sky. Credit: NASA/SDO
Yes, when it comes to the planet Venus, things work quite differently than they do here on Earth. Not only does a day last over half a year on our “Sister Planet”, but the Sun rises and sets on the opposite horizons, and travels across the sky in the opposite direction. The reason for this, according to astronomers, is that billions of years ago (early in the planet’s history) Venus was impacted by another large planet.
The combined momentum between the two objects averaged out to the current rotational speed and direction, causing Venus to spin very slowly in its current retrograde motion. Someday, if human beings colonize there (perhaps in floating cities) they will have to learn to get used to a day that lasts over 2800 Earth hours, not to mention sunrises and sunsets happening on the wrong horizon!
NASA has unveiled a new exercise device that will be used by Orion crews to stay healthy on their mission to Mars. Credit: NASA
Going into space comes with its share of risks. In addition to the possibility of a catastrophic failure happening during take-off or landing, and having your craft pinholed by a micrometeorite, there are also the dangers of spending extended periods in space. Beyond that, there are also the slow, degenerative effects that spending an extended amount of time in a weightless environment can have on your body.
While astronauts on the ISS have enough space for the work-out equipment they need to help reduce these effects (i.e. muscle degeneration and loss of bone density), long-range missions are another matter. Luckily, NASA has plans for how astronauts can stay healthy during their upcoming “Journey to Mars“. It’s known as the Resistive Overload Combined with Kinetic Yo-Yo (ROCKY) device, which will be used aboard the Orion spacecraft.
For years, engineers at NASA and in the private sector have been working to create the components that will take astronauts to the Red Planet in the 2030s. These include the Space Launch System (SLS) and the Orion Multi Purpose Crew Capsule. At the same time, scientists and engineers at the Ohio-based Zin Technologies company – with the support of the NASA Human Research Program’s Exploration Exercise Equipment project – were busy developing the equipment needed to keep the Martian crews healthy and fit in space.
Cutaway of the Orion crew module, showing the ROCKY exercise device in blue, below the side hatch that astronauts will use to get in and out of the spacecraft. Credit: NASA
One of the biggest challenges was making a device that is robust enough to provide a solid work-out, but still be compact and light-weight enough to fit inside the space capsule. What they came up with was ROCKY, a rowing machine-like tool that can accommodate both aerobic activity and strength training. Using loads that simulate up to 180 kg (400 pounds) of resistance, astronauts will be able to perform excises like squats, deadlifts and heel raises, as well as upper body exercises like bicep curls and upright rows.
In the past, astronauts aboard the ISS have relied on equipment like the Mini Exercise Device-2 or the Treadmill Vibration Isolation System (TVIS) to reduce the risks of bone-density loss and muscle degeneration. But as Gail Perusek – the deputy project manager for NASA’s Exploration Exercise Equipment project – explained, developing exercise equipment for the Journey to Mars required something new:
“ROCKY is an ultra-compact, lightweight exercise device that meets the exercise and medical requirements that we have for Orion missions. The International Space Station’s exercise devices are effective but are too big for Orion, so we had to find a way to make exercising in Orion feasible.”
The device can also be customized, and incorporates the best features from a second device known as the Device for Aerobic and Resistive Training (DART). These include a servo-motor programmed to deliver a load profile that feels very similar to free weights. The DART was developed by TDA Research, a Denver-based R&D company, with the support of NASA’s Small Business Innovation Research Program. It was evaluated alongside the ROCKY during the equipment selection process.
The ROCKY device in action. Credit: NASA
In addition to being used for the crewed mission to Mars, the ROCKY device is likely to become a permanent feature aboard the Orion capsule, which will make it a mainstay for all of NASA’s proposed long-duration missions.
As Cindy Haven, the project manager for the Exploration Exercise Equipment Project, explained: “Our long-term goal is to develop a device that’s going to work for us for exploration. Between now and the mission, we’ll have different phases where we’re going to evaluate it for functionality, usability and durability to refine its design.”
The ROCKY device will be tested for the first time on Exploration Mission-2 (EM-2), the first mission where the spacecraft will be launched with a crew aboard. Th ROCKY will be located near the side hatch of the spacecraft, which astronauts will use to get in and out of the capsule. After the Orion is launched, the crew’s seats will be collapsed to provide more interior space for the astronauts as they work out.
And while the early missions using the Orion capsule will span only a few weeks at a time, staying fit will be important in the unlikely event that the astronauts need to get out of the crew module unassisted after splashdown. In the meantime, NASA will be spending the next few years refining the device to optimize it not only for near-term crewed Orion missions, but for potential uses on future long-duration missions.
The ROCKY is likely to become a mainstay for future long-term missions using the Orion space capsule. Credit: NASA
These will include the all-important launch where the Orion will dock with a habitat in the area of space around the moon. These missions are part of Phase II of NASA’s Mars mission, which is known as the “Proving Ground” phase. Scheduled to begin in 2030, this phase will involve the last elements of the mission being launched to cis-lunar orbit, and then all the equipment being sent to near-Mars space for pre-deployment.
The development team that will oversee future refinements will include engineers and scientists from Glenn Research Center in Cleveland, Ohio, and Johnson Space Center in Houston. In addition to building the hardware and ensuring that it is certified for flight, they will also be responsible for incorporating lessons learned from the development of equipment built for the ISS.
If all goes well in the coming years, the team even plans to include ROCKY into the International Space Station’s already impressive array of workout machines. Just another way for the astronauts to beat the slow, degenerative effects of floating freely in space!
Rough visual comparison of Jupiter, Earth, and the Great Red Spot. Approximate scale is 44 km/px. Credit: NASA/Brian0918/ Wikipedia Commons
Ever since Galileo Galilei first observed Jupiter closely in 1610 using a telescope of his own design, scientists and astronomers have been immensely fascinated by the Jovian planet. Not only is it the Solar System’s largest planet, but there are still things about this world – despite centuries of research and numerous exploration missions – that continue to mystify even our greatest minds.
One of the main reasons for this is because Jupiter is so starkly different from what we Earth-dwellers consider to be normal. Between its incredible size, mass, composition, the mysteries of its magnetic and gravitational fields, and its impressive system of moons, its existence has shown us just how diverse planets can truly be.
Size, Mass and Density:
Earth’s has a mean radius of 6,371 km (3,958.8 mi), and a mass of 5.97 × 1024 kg, whereas Jupiter has a mean radius of 69,911 ± 6 km (43441 mi) and a mass of 1.8986×1027 kg. In short, Jupiter is almost 11 times the size of Earth, and just under 318 times as massive. However, Earth’s density is significantly higher, since it is a terrestrial planet – 5.514 g/cm3 compared to 1.326 g/cm³.
Because of this, Jupiter’s “surface” gravity is significantly higher than Earth normal – i.e. 9.8 m/s² or 1 g. While, as a gas giant, Jupiter has no surface per se, astronomers believe that within Jupiter’s atmosphere where the atmospheric pressure is equal to 1 bar (which is equal to Earth’s at sea level), Jupiter experiences a gravitational force of 24.79 m/s2 (which is the equivalent of 2.528 g).
Earth is a terrestrial planet, which means it is composed of silicate minerals and metal that are differentiated between a metal core and a silicate mantle and crust. The core itself is also differentiated, between an inner core and outer core (which spins in the opposite direction of Earth’s rotation). As one descends from the crust to the interior, temperatures and pressure increase.
The shape of Earth approximates that of an oblate spheroid, a sphere flattened along the axis from pole to pole such that there is a bulge around the equator. This bulge results from the rotation of Earth, and causes the diameter at the equator to be 43 kilometers (27 mi) larger than the pole-to-pole diameter.
In contrast, Jupiter is composed primarily of gaseous and liquid matter which is divided between a gaseous outer atmosphere and a denser interior. It’s upper atmosphere is composed of about 88–92% hydrogen and 8–12% helium by volume of gas molecules, and approx. 75% hydrogen and 24% helium by mass, with the remaining one percent consisting of other elements.
The atmosphere contains trace amounts of methane, water vapor, ammonia, and silicon-based compounds as well as trace amounts of benzene and other hydrocarbons. There are also traces of carbon, ethane, hydrogen sulfide, neon, oxygen, phosphine, and sulfur. Crystals of frozen ammonia have also been observed in the outermost layer of the atmosphere.
Jupiter’s structure and composition. (Image Credit: Kelvinsong CC by S.A. 3.0)
The denser interior is composed of roughly 71% hydrogen, 24% helium and 5% other elements by mass. It is believed that Jupiter’s core is a dense mix of elements – a surrounding layer of liquid metallic hydrogen with some helium, and an outer layer predominantly of molecular hydrogen. The core has also been inferred as being rocky, but this remains unknown as well.
And much like Earth, temperatures and pressures inside Jupiter increase dramatically toward the core. At the “surface”, the pressure and temperature are believed to be 10 bars and 340 K (67 °C, 152 °F). In the region where hydrogen becomes metallic, it is believed that temperatures reach 10,000 K (9,700 °C; 17,500 °F) and pressures 200 GPa. The temperature at the core boundary is estimated to be 36,000 K (35,700 °C; 64,300 °F) and the interior pressure at roughly 3,000–4,500 GPa.
Also like Earth, Jupiter’s shape is that of an oblate spheroid. In fact, Jupiter’s polar flattening is greater than that of Earth’s – 0.06487 ± 0.00015 compared to 0.00335. This is due to Jupiter’s rapid rotation on its axis, and is why the planet’s equatorial radius is approximately 4600 km larger than its polar radius.
Orbital Parameters:
Earth has a very minor orbital eccentricity (approx. 0.0167) and ranges in distance from 147,095,000 km (0.983 AU) from the Sun at perihelion to 151,930,000 km (1.015 AU) at aphelion. This works out to an average distance (aka. semi-major axis) of 149,598,261 km, which is the basis of a single Astronomical Unit (AU).
The orbits of the inner planets of the Solar System, with Jupiter and the donut-shaped asteroid belt is located between them. Credit: Wikipedia Commons
The Earth has an orbital period of 365.25 days, which is the equivalent of 1.000017 Julian years. This means that every four years (in what is known as a Leap Year), the Earth calendar must include an extra day. Though technically a full day is considered to be 24 hours long, our planet takes precisely 23h 56m and 4 s to complete a single sidereal rotation (0.997 Earth days). But combined with its orbital period around the Sun, the time between one sunrise and another (a Solar Day) is 24 hours.
Viewed from the celestial north pole, the motion of Earth and its axial rotation appear counterclockwise. From the vantage point above the north poles of both the Sun and Earth, Earth orbits the Sun in a counterclockwise direction. Earth’s axis is tilted also 23.4° towards the ecliptic of the Sun, which is responsible for producing seasonal variations on the planet’s surface. In addition to producing variations in temperature, this also results in variations in the amount of sunlight a hemisphere receives during the course of a year.
Meanwhile, Jupiter orbits the Sun at an average distance (semi-major axis) of 778,299,000 km (5.2 AU), ranging from 740,550,000 km (4.95 AU) at perihelion and 816,040,000 km (5.455 AU) at aphelion. At this distance, Jupiter takes 11.8618 Earth years to complete a single orbit of the Sun. In other words, a single Jovian year lasts the equivalent of 4,332.59 Earth days.
The banded appearance of Jupiter’s upper atmopshere, which is partly due to its rapid rotation. Credit: NASA
However, Jupiter’s rotation is the fastest of all the Solar System’s planets, completing a single rotation on its axis in slightly less than ten hours (9 hours, 55 minutes and 30 seconds). Therefore, a single Jovian year lasts 10,475.8 Jovian solar days.
Atmospheres:
Earth’s atmosphere is made up of five main layers – the Troposphere, the Stratosphere, the Mesosphere, the Thermosphere, and the Exosphere. As a rule, air pressure and density decrease the higher one goes into the atmosphere and the farther one is from the surface. However, the relationship between temperature and altitude is more complicated, and may even rise with altitude in some cases.
The troposphere contains roughly 80% of the mass of Earth’s atmosphere, with some 50% located in the lower 5.6 km (3.48 mi), making it denser than all its overlying atmospheric layers. It is primarily composed of nitrogen (78%) and oxygen (21%) with trace concentrations of water vapor, carbon dioxide, and other gaseous molecules.
Nearly all atmospheric water vapor or moisture is found in the troposphere, so it is the layer where most of Earth’s meteorological phenomena (clouds, rain, snow, lightning storms) take place. The one exception is the Thermoposphere, where the phenomena known as Aurora Borealis and Aurara Australis (aka. The Northern and Southern Lights) are known to take place.
As already noted, Jupiter’s atmosphere is composed primarily of hydrogen and helium, with trace amounts of other elements. Much like Earth, Jupiter experiences auroras near its northern and southern poles. But on Jupiter, the auroral activity is much more intense and rarely ever stops. The intense radiation, Jupiter’s magnetic field, and the abundance of material from Io’s volcanoes that react with Jupiter’s ionosphere create a light show that is truly spectacular.
Jupiter also experiences violent weather patterns. Wind speeds of 100 m/s (360 km/h) are common in zonal jets, and can reach as high as 620 kph (385 mph). Storms form within hours and can become thousands of km in diameter overnight. One storm, the Great Red Spot, has been raging since at least the late 1600s. The storm has been shrinking and expanding throughout its history; but in 2012, it was suggested that the Giant Red Spot might eventually disappear.
Jupiter is perpetually covered with clouds composed of ammonia crystals and possibly ammonium hydrosulfide. These clouds are located in the tropopause and are arranged into bands of different latitudes, known as “tropical regions”. The cloud layer is only about 50 km (31 mi) deep, and consists of at least two decks of clouds: a thick lower deck and a thin clearer region.
Composite images from the Chandra X-Ray Observatory and the Hubble Space Telescope show the hyper-energetic x-ray auroras at Jupiter. Credit: NASA/CXC/UCL/W.Dunn et al/STScI
There may also be a thin layer of water clouds underlying the ammonia layer, as evidenced by flashes of lightning detected in the atmosphere of Jupiter, which would be caused by the water’s polarity creating the charge separation needed for lightning. Observations of these electrical discharges indicate that they can be up to a thousand times as powerful as those observed here on the Earth.
Moons:
Earth has only one orbiting satellite, The Moon. It’s existence has been known of since prehistoric times, and it has played a major role in the mythological and astronomical traditions of all human cultures and has a significant effect on Earth’s tides. In the modern era, the Moon has continued to serve as a focal point for astronomical and scientific research, as well as space exploration.
In fact, the Moon is the only celestial body outside of Earth that humans have actually walked on. The first Moon landing took place on July 20th, 1969, and Neil Armstrong was the first person to set foot on the surface. Since that time, a total of 13 astronauts have been to the Moon, and the research that they carried out has been instrumental in helping us to learn about its composition and formation.
Thanks to examinations of Moon rocks that were brought back to Earth, the predominant theory states that the Moon was created roughly 4.5 billion years ago from a collision between Earth and a Mars-sized object (known as Theia). This collision created a massive cloud of debris that began circling our planet, which eventually coalesced to form the Moon we see today.
Illustration of Jupiter and the Galilean satellites. Credit: NASA
The Moon is one of the largest natural satellites in the Solar System and is the second-densest satellite of those whose densities are known (after Jupiter’s satellite Io). It is also tidally locked with Earth, meaning that one side is constantly facing towards us while the other is facing away. The far side, known as the “Dark Side”, remained unknown to humans until probes were sent to photograph it.
The Jovian system, on the other hand, has 67 known moons. The four largest are known as the Galilean Moons, which are named after their discoverer, Galileo Galilei. They include: Io, the most volcanically active body in our Solar System; Europa, which is suspected of having a massive subsurface ocean; Ganymede, the largest moon in our Solar System; and Callisto, which is also thought to have a subsurface ocean and features some of the oldest surface material in the Solar System.
Then there’s the Inner Group (or Amalthea group), which is made up of four small moons that have diameters of less than 200 km, orbit at radii less than 200,000 km, and have orbital inclinations of less than half a degree. This groups includes the moons of Metis, Adrastea, Amalthea, and Thebe. Along with a number of as-yet-unseen inner moonlets, these moons replenish and maintain Jupiter’s faint ring system.
Jupiter also has an array of Irregular Satellites, which are substantially smaller and have more distant and eccentric orbits than the others. These moons are broken down into families that have similarities in orbit and composition, and are believed to be largely the result of collisions from large objects that were captured by Jupiter’s gravity.
In just about every way imaginable, Earth and Jupiter could not be more different. And there are still many things about the Jovian planet that we do not yet fully understand. Speaking of which, be sure to stay tuned to Universe Today for the latest updates from NASA’s Juno mission.
A section of the 3D map constructed by BOSS. The rectangle on the far left shows a cutout of 1000 sq. degrees in the sky containing nearly 120,000 galaxies, or roughly 10% of the total survey. Credit: Jeremy Tinker/SDSS-III
In 1929, Edwin Hubble forever changed our understanding of the cosmos by showing that the Universe is in a state of expansion. By the 1990s, astronomers determined that the rate at which it is expanding is actually speeding up, which in turn led to the theory of “Dark Energy“. Since that time, astronomers and physicists have sought to determine the existence of this force by measuring the influence it has on the cosmos.
The latest in these efforts comes from the Sloan Digital Sky Survey III (SDSS III), where an international team of researchers have announced that they have finished creating the most precise measurements of the Universe to date. Known as the Baryon Oscillation Spectroscopic Survey (BOSS), their measurements have placed new constraints on the properties of Dark Energy.
The new measurements were presented by Harvard University astronomer Daniel Eisenstein at a recent meeting of the American Astronomical Society. As the director of the Sloan Digital Sky Survey III (SDSS-III), he and his team have spent the past ten years measuring the cosmos and the periodic fluctuations in the density of normal matter to see how galaxies are distributed throughout the Universe.
An illustration of baryon acoustic oscillations, which are imprinted in the early universe and can still be seen today in galaxy surveys like BOSS. Credit: Chris Blake and Sam Moorfield
And after a decade of research, the BOSS team was able to produce a three-dimensional map of the cosmos that covers more than six billion light-years. And while other recent surveys have looked further afield – up to distances of 9 and 13 billion light years – the BOSS map is unique in that it boasts the highest accuracy of any cosmological map.
In fact, the BOSS team was able to measure the distribution of galaxies in the cosmos, and at a distance of 6 billion light-years, to within an unprecedented 1% margin of error. Determining the nature of cosmic objects at great distances is no easy matter, due the effects of relativity. As Dr. Eisenstein told Universe Today via email:
“Distances are a long-standing challenge in astronomy. Whereas humans often can judge distance because of our binocular vision, galaxies beyond the Milky Way are much too far away to use that. And because galaxies come in a wide range of intrinsic sizes, it is hard to judge their distance. It’s like looking at a far-away mountain; one’s judgement of its distance is tied up with one’s judgement of its height.”
In the past, astronomers have made accurate measurements of objects within the local universe (i.e. planets, neighboring stars, star clusters) by relying on everything from radar to redshift – the degree to which the wavelength of light is shifted towards the red end of the spectrum. However, the greater the distance of an object, the greater the degree of uncertainty.
An artist’s concept of the latest, highly accurate measurement of the Universe from BOSS. Credit: Zosia Rostomian/Lawrence Berkeley National Laboratory
And until now, only objects that are a few thousand light-years from Earth – i.e. within the Milky Way galaxy – have had their distances measured to within a one-percent margin of error. As the largest of the four projects that make up the Sloan Digital Sky Survey III (SDSS-III), what sets BOSS apart is the fact that it relies primarily on the measurement of what are called “baryon acoustic oscillations” (BAOs).
These are essentially subtle periodic ripples in the distribution of visible baryonic (i.e. normal) matter in the cosmos. As Dr. Daniel Eisenstein explained:
“BOSS measures the expansion of the Universe in two primary ways. The first is by using the baryon acoustic oscillations (hence the name of the survey). Sound waves traveling in the first 400,000 years after the Big Bang create a preferred scale for separations of pairs of galaxies. By measuring this preferred separation in a sample of many galaxies, we can infer the distance to the sample.
“The second method is to measure how clustering of galaxies differs between pairs oriented along the line of sight compared to transverse to the line of sight. The expansion of the Universe can cause this clustering to be asymmetric if one uses the wrong expansion history when converting redshifts to distance.”
With these new, highly-accurate distance measurements, BOSS astronomers will be able to study the influence of Dark Matter with far greater precision. “Different dark energy models vary in how the acceleration of the expansion of the Universe proceeds over time,” said Eisenstein. “BOSS is measuring the expansion history, which allows us to infer the acceleration rate. We find results that are highly consistent with the predictions of the cosmological constant model, that is, the model in which dark energy has a constant density over time.”
Discerning the large-scale structure of the universe, and the role played by Dark Energy, is key to unlocking its mysteries. Credit: NAOJ/CFHT/ SDSS
In addition to measuring the distribution of normal matter to determine the influence of Dark Energy, the SDSS-III Collaboration is working to map the Milky Way and search for extrasolar planets. The BOSS measurements are detailed in a series of articles that were submitted to journals by the BOSS collaboration last month, all of which are now available online.
And BOSS is not the only effort to understand the large-scale structure of our Universe, and how all its mysterious forces have shaped it. Just last month, Professor Stephen Hawking announced that the COSMOS supercomputing center at Cambridge University would be creating the most detailed 3D map of the Universe to date.
Relying on data obtained by the CMB data obtained by the ESA’s Planck satellite and information from the Dark Energy Survey, they also hope to measure the influence Dark Energy has had on the distribution of matter in our Universe. Who knows? In a few years time, we may very well come to understand how all the fundamental forces governing the Universe work together.
A team of NASA engineers has fashioned the world's first telescope mirrors made from carbon nanotubes. Credit: NASA
Ever since they were first produced, carbon nanotubes have managed to set off a flurry excitement in the scientific community. With applications ranging from water treatment and electronics, to biomedicine and construction, this should come as no surprise. But a team of NASA engineers from the Goddard Space Flight Center in Greenbelt, Maryland, has pioneered the use of carbon nanotubes for yet another purpose – space-based telescopes.
Using carbon nanotubes, the Goddard team – which is led by Dr. Theodor Kostiuk of NASA’s Planetary Systems Laboratory and Solar System Exploration Division – have created a revolutionary new type of telescope mirror. These mirrors will be deployed as part of a CubeSat, one which may represent a new breed of low-cost, highly effective space-based telescopes.
This latest innovation also takes advantage of another field that has seen a lot of development of late. CubeSats, like other small satellites, have been playing an increasingly important role in recent years. Unlike the larger, bulkier satellites of yesteryear, miniature satellites are a low-cost platform for conducting space missions and scientific research.
Dr. Ted Kostiuk (center), flanked by John Kolasinski (left), and Tilak Hewagama (right), holding mirrors made of carbon nanotubes in an epoxy resin. Credit: NASA/W. Hrybyk
Beyond federal space agencies like NASA, they also offer private business and research institutions the opportunity to conduct communications, research and observation from space. On top of that, they are also a low-cost way to engage students in all phases of satellite construction, deployment, and space-based research.
Granted, missions that rely on miniature satellites are not likely to generate the same amount of interest or scientific research as large-scale operations like the Juno mission or the New Horizons space probe. But they can provide vital information as part of larger missions, or work in groups to gather greater amounts of data.
With the help of funding from Goddard’s Internal Research and Development program, the team created a laboratory optical bench made of regular off-the-shelf components to test the telescope’s overall design. This bench consists of a series of miniature spectrometers tuned to the ultraviolet, visible, and near-infrared wavelengths, which are connected to the focused beam of the nanotube mirrors via an optic cable.
Using this bench, the team is testing the optical mirrors, seeing how they stand up to different wavelengths of light. Peter Chen – the president of Lightweight Telescopes a Maryland-based company – is one of the contractors working with the Goddard team to create the CubeSat telescope. As he was quoted as saying by a recent NASA press release:
“No one has been able to make a mirror using a carbon-nanotube resin. This is a unique technology currently available only at Goddard. The technology is too new to fly in space, and first must go through the various levels of technological advancement. But this is what my Goddard colleagues (Kostiuk, Tilak Hewagama, and John Kolasinski) are trying to accomplish through the CubeSat program.
The laboratory breadboard that is being used to test a conceptual telescope for use on CubeSat missions. Credits: NASA/W. Hrybyk
Unlike other mirrors, the one created by Dr. Kostiuk’s team was fabricated out of carbon nanotubes embedded in an epoxy resin. Naturally, carbon nanotubes offer a wide range of advantages, not the least of which are structural strength, unique electrical properties, and efficient conduction of heat. But the Goddard team also chose this material for their lenses because it offers a lightweight, highly stable and easily reproducible option for creating telescope mirrors.
What’s more, mirrors made of carbon-nanotubes do not require polishing, which is a time-consuming and expensive process when it comes to space-based telescopes. The team hopes that this new method will prove useful in creating a new class of low-cost, CubeSat space telescopes, as well as helping to reduce costs when it comes to larger ground-based and space-based telescopes.
Such mirrors would be especially useful in telescopes that use multiple mirror segments (like the Keck Observatory at Mauna Kea and the James Webb Space Telescope). Such mirrors would be a real cost-cutter since they can be easily produced and would eliminate the need for expensive polishing and grinding.
Other potential applications include deep-space communications, improved electronics, and structural materials for spacecraft. Currently, the production of carbon nanotubes is quite limited. But as it becomes more widespread, we can expect this miracle material to be making its way into all aspects of space exploration and research.
Artist's impression of The Milky Way Galaxy. Based on current estimates and exoplanet data, it is believed that there could be tens of billions of habitable planets out there. Credit: NASA
For thousand of years, astronomers and astrologers believed that the Earth was at the center of our Universe. This perception was due in part to the fact that Earth-based observations were complicated by the fact that the Earth is embedded in the Solar System. It was only after many centuries of continued observation and calculations that we discovered that the Earth (and all other bodies in the Solar System) actually orbits the Sun.
Much the same is true about our Solar System’s position within the Milky Way. In truth, we’ve only been aware of the fact that we are part of a much larger disk of stars that orbits a common center for about a century. And given that we are embedded within it, it has been historically difficult to ascertain our exact position. But thanks to ongoing efforts, astronomers now know where our Sun resides in the galaxy.
Size of the Milky Way:
For starters, the Milky Way is really, really big! Not only does it measure some 100,000–120,000 light-years in diameter and about 1,000 light-years thick, but up to 400 billion stars are located within it (though some estimates think there are even more). Since one light year is about 9.5 x 1012 km (9.5 trillion km) long, the diameter of the Milky Way galaxy is about 9.5 x 1017 to 11.4 x 1017 km, or 9,500 to 11,400 quadrillion km.
It became its current size and shape by eating up other galaxies, and is still doing so today. In fact, the Canis Major Dwarf Galaxy is the closest galaxy to the Milky Way because its stars are currently being added to the Milky Way’s disk. And our galaxy has consumed others in its long history, such as the Sagittarius Dwarf Galaxy.
And yet, our galaxy is only a middle-weight when compared to other galaxies in the local Universe. Andromeda, the closest major galaxy to our own, is about twice as large as our own. It measures 220,000 light years in diameter, and has an estimated 400-800 billion stars within it.
Structure of the Milky Way:
If you could travel outside the galaxy and look down on it from above, you’d see that the Milky Way is a barred spiral galaxy. For the longest time, the Milky Way was thought to have 4 spiral arms, but newer surveys have determined that it actually seems to just have two spiral arms, called Scutum–Centaurus and Carina–Sagittarius.
The spiral arms are formed from density waves that orbit around the Milky Way – i.e. stars and clouds of gas clustered together. As these density waves move through an area, they compress the gas and dust, leading to a period of active star formation for the region. However, the existence of these arms has been determined from observing parts of the Milky Way – as well as other galaxies in our universe.
The Milky Way’s basic structure is believed to involve two main spiral arms emanating from opposite ends of an elongated central bar. Credit: T. Dame
In truth, all the pictures that depict our galaxy are either artist’s renditions or pictures of other spiral galaxies, and not the result of direct observation of the whole. Until recently, it was very difficult for scientists to gauge what the Milky Way really looks like, mainly because we’re inside it. It has only been through decades of observation, reconstruction and comparison to other galaxies that they have been to get a clear picture of what the Milky Way looks like from the outside.
From ongoing surveys of the night sky with ground-based telescopes, and more recent missions involving space telescopes, astronomers now estimate that there are between 100 and 400 billion stars in the Milky Way. They also think that each star has at least one planet, which means there are likely to be hundreds of billions of planets in the Milky Way – billions of which are believed to be the size and mass of the Earth.
As noted, much of the Milky Way’s arms is made up of dust and gas. This matter makes up a whopping 10-15% of all the “luminous matter” (i.e. that which is visible) in our galaxy, with the remainder being the stars. Our galaxy is roughly 100,000 light years across, and we can only see about 6,000 light years into the disk in the visible spectrum.
Still, when light pollution is not significant, the dusty ring of the Milky Way can be discerned in the night sky. What’s more, infrared astronomy and viewing the Universe in other, non-visible wavelengths has allowed astronomers to be able to see more of it.
The Milky Way, like all galaxies, is also surrounded by a vast halo of dark matter, which accounts for some 90% of its mass. Nobody knows precisely what dark matter is, but its mass has been inferred by observations of how fast the galaxy rotates and other general behaviors. More importantly, it is believed that this mass helps keep the galaxy from tearing itself apart as it rotates.
The Solar System:
The Solar System (and Earth) is located about 25,000 light-years to the galactic center and 25,000 light-years away from the rim. So basically, if you were to think of the Milky Way as a big record, we would be the spot that’s roughly halfway between the center and the edge.
Astronomers have agreed that the Milky Way probably has two major spiral arms – Perseus arm and the Scutum-Centaurus arm – with several smaller arms and spurs. The Solar System is located in a region in between the two arms called the Orion-Cygnus arm. This arm measures 3,500 light-years across and is 10,000 light-years in length, where it breaks off from the Sagittarius Arm.
The location of our Solar Systemin the Orion Spur of the Milky Way galaxy. Credit: Roberto Mura/Public Domain
The fact that the Milky Way divides the night sky into two roughly equal hemispheres indicates that the Solar System lies near the galactic plane. The Milky Way has a relatively low surface brightness due to the gases and dust that fills the galactic disk. That prevents us from seeing the bright galactic center or from observing clearly what is on the other side of it.
You might be surprised to learn that it takes the Sun 250 million years to complete one rotation around the Milky Way – this is what is known as a “Galactic Year” or “Cosmic Year”. The last time the Solar System was in this position in the Milky Way, there were still dinosaurs on Earth. The next time, who knows? Humanity might be extinct, or it might have evolved into something else entirely.
As you can see, the Milky Way alone is a very big place. And discerning our location within it has been no simple task. And as our knowledge of the Universe has expanded, we’ve come to learn two things. Not only is the Universe much larger than we could have ever imagined, but our place within in continues to shrink! Our Solar System, it seems, is both insignificant in the grand scheme of things, but also extremely precious!
