Since the turn of the century, space exploration has changed dramatically thanks to the unprecedented rise of commercial aerospace (aka. NewSpace). With the goal of leveraging new technologies and lowering the costs of launching payloads into space, some truly innovative and novel ideas are being put forth. This includes the idea of using balloons to carry rockets to very high-altitudes, then firing the payloads to their desired orbits.
Also known as “Rockoons”, this concept has informed Leo Aerospace‘s fully-autonomous and fully-reusable launch system – which consists of a high-altitude aerostat (balloon) and a rocket launch platform. With the first commercial launches slated for next year, the company plans to use this system to provide regular launch services to the microsatellite (aka. CubeSat) market in the coming years.
The Indian Space Research Organization (ISRO) has made immense progress since the turn of the century. From its humble beginnings, launching satellites into orbit between 1975 and 2000, the ISRO sent their first mission to the Moon in October of 2008 (the Chandrayaan-1 orbiter), followed by their first mission to Mars – the Mars Orbiter Mission (MOM) – in November of 2013.
And in the coming years, the ISRO intends to become the fourth space agency to send astronauts into space. In so doing, they will join an exclusive club of space agencies that consists of only Russia, the United States and China. Last week (on September 7th, 2018) the organization unveiled the spacesuit that their astronauts will be wearing when they make this historic journey.
After almost seventy years of spaceflight, space debris has become a rather serious problem. This junk, which floats around in Low Earth Orbit (LEO), consists of the spent first rocket stages and non-functioning satellites and poses a major threat to long-term missions like the International Space Station and future space launches. And according to numbers released by the Space Debris Office at the European Space Operations Center (ESOC), the problem is only getting worse.
In addition, space agencies and private aerospace companies hope to launch considerably more in the way of satellites and space habitats in the coming years. As such, NASA has begun experimenting with a revolutionary new idea for removing space debris. It is known as the RemoveDebris spacecraft, which recently deployed from the ISS to conduct a series of Active Debris Removal (ADR) technology demonstrations.
This satellite was assembled by Surrey Satellite Technology Ltd. and the Surrey Space Center (at the University of Surrey in the UK) and contains experiments provided by multiple European aerospace companies. It measures roughly 1 meter (3 feet) on a side and weighs about 100 kg (220 lbs), making it the largest satellite deployed to the ISS to date.
The purpose of the RemoveDebris spacecraft is to demonstrate the effectiveness of debris nets and harpoons at capturing and removing space debris from orbit. As Sir Martin Sweeting, the Chief Executive of SSTL, said in a recent statement:
“SSTL’s expertise in designing and building low cost, small satellite missions has been fundamental to the success of RemoveDEBRIS, a landmark technology demonstrator for Active Debris Removal missions that will begin a new era of space junk clearance in Earth’s orbit.”
Aside from the Surrey Space Center and SSTL, the consortium behind the RemoveDebris spacecraft includes Airbus Defense and Space – the world’s second largest space company – Airbus Safran Launchers, Innovative Solutions in Space (ISIS), CSEM, Inria, and Stellenbosch University. The spacecraft, according to the Surrey Space Center’s website, consists of the following:
“The mission will comprise of a main satellite platform (~100kg) that once in orbit will deploy two CubeSats as artificial debris targets to demonstrate some of the technologies (net capture, harpoon capture, vision-based navigation, dragsail de-orbitation). The project is co-funded by the European Commission and the project partners, and is led by the Surrey Space Centre (SSC), University of Surrey, UK.”
For the sake of the demonstration, the “mothership” will deploy two cubesates which will simulate two pieces of space junk. For the first experiment, one of the CubeSats – designated DebrisSat 1 – will inflate its onboard balloon in order to simulate a larger piece of junk. The RemoveDebris spacecraft will then deploy its net to capture it, then guide it into the Earth’s atmosphere where the net will be released.
The second CubeSat, named DebrisSat 2, will be used to test the mothership’s tracking and ranging lasers, its algorithms, and its vision-based navigation technology. The third experiment, which will test the harpoon’s ability to capture orbiting space debris, is set to take place next March. For legal reasons, the harpoon will not be tested on an actual satellite, and will instead consist of the mothership extending an arm with a target on the end.
The harpoon will then be fired on a tether at 20 meters per second (45 mph) to tests it accuracy. After being launched to the station back on April 2nd, the satellite was deployed from the ISS’ Japanese Kibo lab module on June 20th by the stations’ Canadian robotic arm. As Guillermo Aglietti, the director of the Surrey Space Center, explained in an interview with SpaceFlight Now before the spacecraft was launched to the ISS:
“The net, as a way to capture debris, is a very flexible option because even if the debris is spinning, or has got an irregular shape, to capture it with a net is relatively low-risk compared to … going with a robotic arm, because if the debris is spinning very fast, and you try to capture it with a robotic arm, then clearly there is a problem. In addition, if you are to capture the debris with a robotic arm or a gripper, you need somewhere you can grab hold of your piece of debris without breaking off just a chunk of it.”
The net experiment is currently scheduled for September of 2018 while the second experiment is scheduled for October. When these experiments are complete, the mothership will deploy its dragsail to act as a braking mechanism. This expandable sail will experience collisions with air molecules in the Earth’s outer atmosphere, gradually reducing its orbit until it enters the denser layers of Earth’s atmosphere and burns up.
This sail will ensure that the spacecraft deorbits within eights weeks of its deployment, rather than the estimated two-and-half years it would take to happen naturally. In this respect, the RemoveDebris spacecraft will demonstrate that it is capable of tackling the problem of space debris while not adding to it.
In the end, the RemoveDebris spacecraft will test a number of key technologies designed to make orbital debris removal as simple and cost-effective as possible. If it proves effective, the ISS could be receiving multiple RemoveDebris spacecraft in the ftureu, which could then be deployed gradually to remove larger pieces of space debris that threaten the station and operational satellites.
Conor Brown is the external payloads manager of Nanoracks LLC, the company that developed the Kaber system aboard the Kibo lab module to accommodate the increasing number of MicroSats being deployed from the ISS. As he expressed in a recent statement:
“It’s wonderful to have helped facilitate this ground-breaking mission. RemoveDebris is demonstrating some extremely exciting active debris removal technologies that could have a major impact to how we manage space debris moving forward. This program is an excellent example of how small satellite capabilities have grown and how the space station can serve as a platform for missions of this scale. We’re all excited to see the results of the experiments and impact this project may have in the coming years.”
In addition to the RemoveDebris spacecraft, the ISS recently received a new tool for detecting space debris. This is known as the Space Debris Sensor (SDS), a calibrated impact sensor mounted on the exterior of the station to monitor impacts caused by small-scale space debris. Coupled with technologies designed to clean up space debris, improved monitoring will ensure that the commercialization (and perhaps even colonization) of LEO can begin.
Orbital debris (aka. space junk) is one of the greatest problems facing space agencies today. After sixty years of sending rockets, boosters and satellites into space, the situation in the Low Earth Orbit (LEO) has become rather crowded. Given how fast debris in orbit can travel, even the tiniest bits of junk can pose a major threat to the International Space Station and threaten still-active satellites.
It’s little wonder then why ever major space agency on the planet is committed to monitoring orbital debris and creating countermeasures for it. So far, proposals have ranged from giant magnets and nets and harpoons to lasers. Given their growing presence in space, China is also considering developing giant space-based lasers as a possible means for combating junk in orbit.
For the sake of their study, the team conducted numerical simulations to see if an orbital station with a high-powered pulsed laser could make a dent in orbital debris. Based on their assessments of the velocity and trajectories of space junk, they found that an orbiting laser that had the same Right Ascension of Ascending Node (RAAN) as the debris itself would be effective at removing it. As they state in their paper:
“The simulation results show that, debris removal is affected by inclination and RAAN, and laser station with the same inclination and RAAN as debris has the highest removal efficiency. It provides necessary theoretical basis for the deployment of space-based laser station and the further application of space debris removal by using space-based laser.”
This is not the first time that directed-energy has been considered as a possible means of removing space debris. However, the fact that China is investigating directed-energy for the sake of debris removal is an indication of the nation’s growing presence in space. It also seems appropriate since China is considered to be one of the worst offenders when to comes to producing space junk.
Back in 2007, China conducted a anti-satellite missile test that resulted in the creation over 3000 of bits of dangerous debris. This debris cloud was the largest ever tracked, and caused significant damage to a Russian satellite in 2013. Much of this debris will remain in orbit for decades, posing a significant threat to satellites, the ISS and other objects in LEO.
Of course, there are those who fear that the deployment of lasers to LEO will mean the militarization of space. In accordance with the 1966 Outer Space Treaty, which was designed to ensure that the space exploration did not become the latest front in the Cold War, all signatories agreed to “not place nuclear weapons or other weapons of mass destruction in orbit or on celestial bodies or station them in outer space in any other manner.”
In the 1980s, China was added to the treaty and is therefore bound to its provisions. But back in March of 2017, US General John Hyten indicated in an interview with CNN that China’s attempts to develop space-based laser arrays constitutes a possible breach of this treaty:
“They’ve been building weapons, testing weapons, building weapons to operate from the Earth in space, jamming weapons, laser weapons, and they have not kept it secret. They’re building those capabilities to challenge the United States of America, to challenge our allies…We cannot allow that to happen.”
Such concerns are quite common, and represent a bit of a stumbling block when it comes to the use of directed-energy platforms in space. While orbital lasers would be immune to atmospheric interference, thus making them much more effective at removing space debris, they would also lead to fears that these lasers could be turned towards enemy satellites or stations in the event of war.
As always, space is subject to the politics of Earth. At the same time, it also presents opportunities for cooperation and mutual assistance. And since space debris represents a common problem and threatens any and all plans for the exploration of space and the colonization of LEO, cooperative efforts to address it are not only desirable but necessary.
Beginning in the 1950s with the Sputnik, Vostok and Mercury programs, human beings began to “slip the surly bonds of Earth”. And for a time, all of our missions were what is known as Low-Earth Orbit (LEO). Over time, with the Apollo missions and deep space missions involving robotic spacecraft (like the Voyager missions), we began to venture beyond, reaching the Moon and other planets of the Solar System.
But by and large, the vast majority of missions to space over the years – be they crewed or uncrewed – have been to Low-Earth Orbit. It is here that the Earth’s vast array of communications, navigation and military satellites reside. And it is here that the International Space Station (ISS) conducts its operations, which is also where the majority of crewed missions today go. So just what is LEO and why are we so intent on sending things there? Continue reading “What is Low Earth Orbit?”
The Earth’s atmosphere is a total drag, especially if you’re trying to orbit our planet. So how low can you go?
The Earth’s atmosphere is a total drag, especially if you’re trying to orbit our planet. It’s a drag. Get it? Atmospheric drag. Drag. Drag.
Hi, my name is Fraser Cain. I’m the publisher of Universe Today, and sometimes my team lets me write my own jokes.
I could have started off this episode with a reference to the “Adama Drop” in-atmosphere viper deployment from BSG, but instead I went with a Dad joke. My punishment is drawing attention to it.
So how low can you go? And if you go low enough, will Ludacris appear in the mirror?
We all appreciate the Earth’s atmosphere and everything it does for you. With all the breathing, and the staying warm and the not having horrible bruises all over your body from teeny space rocks pummeling us.
I’ve got an alternative view. The Earth’s atmosphere is your gilded pressurized oxygenated cage, and it’s the one thing keeping you from flying in space.And as we all know, this is your destiny.
Without the atmosphere, you could easily orbit the Earth, a few kilometers over its surface. Traveling around and around the planet like a person sized Moon. Wouldn’t that be great?
Well, it’s not going to happen. As you walk through the atmosphere, you bonk into all the air molecules. You don’t feel it when you’re moving at walking speed, but go faster, like an airplane, and it’ll rock you like a hurricane.
Without constant thrust pushing against the atmosphere, you’ll keep slowing down, and when you’re trying to orbit the planet, it’s a killer. Our atmosphere is like someone is constantly pushing the brakes on the fly in space party.
If you’ve played Kerbal Space Program, you know the faster you’re traveling, the higher you orbit. Conversely, the slower you travel, the lower you orbit. Travel slow enough and you’ll eat it, and by it, I meant as much planet as you can co-exist with after a high speed impact.
Being more massive means more momentum to push against the atmospheric drag. But with a large surface area, it acts like a parachute, slowing you down.
Hey, I know something that’s super massive with a huge surface area. The International Space Station orbits the planet at an altitude between 330 km and 435 km.
Why such a big range? The atmosphere is constantly pushing against the ISS as it orbits the planet. This slows down the space station’s speed and lowers its orbit. It wouldn’t last more than a couple of years if it wasn’t able to counteract the atmospheric drag.
Fortunately, the station has rockets to increase its speed, and a faster speed means a higher orbit. It can even get assistance from docked spacecraft. If the space station were to go any lower, it would require higher and higher amounts of thrust to prevent re-entry into the Earth’s atmosphere.
So what are the limits? Anything below 160 km altitude will essentially re-enter almost immediately, as it’s buffeted by the thicker atmosphere. You really wouldn’t last more than a few hours at that altitude, but above 800 km you could orbit for more than 100 years.
Geosynchronous satellites that orbit the Earth and transmit our television signals are at an altitude of about 42,000 km. Satellites that high are never coming back down. Well, maybe not never.
Want to enjoy your orbital experience? Make sure you get yourself to an altitude of at least 300 km, 400 km just to be safe. You should shoot for more like 800 km if you just don’t want to worry about things for a while.
Knowing these risks, would you be willing to travel to orbit with current technology? Tell us in the comments below.
Astronauts aboard the International Space Station are going to be getting an addition in the near future, and in the form of an inflatable room no less. The Bigelow Expandable Activity Module (BEAM) is the first privately-built space habitat that will added to the ISS, and it will be transported into orbit aboard a Space X Falcon 9 rocket sometime next year.
“The BEAM is one small step for Bigelow Aerospace,” Bigelow representative Michael Gold told Universe Today, “but is also one giant leap for private sector space activities since the BEAM will be the first privately owned and developed module ever to be part of a crewed system in space.”
The full scale CST-100 mockup was unveiled at an invitation only ceremony for Boeing executives and media held inside a newly renovated shuttle era facility at the Kennedy Space Center where the capsule would start being manufactured later this year.
Universe Today was invited to tour the capsule for a first hand inspection of the CST-100’s interior and exterior and presents my photo gallery here.
The CST-100 is a privately built manrated capsule being developed with funding from NASA under the auspices of the agency’s Commercial Crew Program (CCP) in a public/private partnership between NASA and private industry.
The vehicle will be assembled inside the refurbished processing hangar known during the shuttle era as Orbiter Processing Facility-3 (OPF-3). Boeing is leasing the site from Space Florida.
Boeing is one of three American aerospace firms vying for a NASA contract to build an American ‘space taxi’ to ferry US astronauts to the space station and back as soon as 2017.
NASA will award one or more contracts to build Americas next human rated spaceship in August or September.
Since the forced shutdown of NASA’s Space Shuttle program following its final flight in 2011, US astronauts have been 100% dependent on the Russians and their cramped but effective Soyuz capsule for rides to the station and back – at a cost exceeding $70 million per seat.
Chris Ferguson, the final shuttle commander for NASA’s last shuttle flight (STS-135) now serves as director of Boeing’s Crew and Mission Operations.
Ferguson and the Boeing team are determined to get Americans back into space from American soil with American rockets.
Read my exclusive, in depth one-on-one interviews with Chris Ferguson – America’s last shuttle commander – about the CST-100; here and here.
The vehicle includes five recliner seats, a hatch and windows, the pilots control console with several attached Samsung tablets for crew interfaces with wireless internet, a docking port to the ISS and ample space for 220 kilograms of cargo storage of an array of equipment, gear and science experiments depending on NASA’s allotment choices.
The interior features Boeing’s LED Sky Lighting with an adjustable blue hue based on its 787 Dreamliner airplanes to enhance the ambience for the crew.
The reusable capsule will launch atop a man rated United Launch Alliance (ULA) Atlas V rocket.
Stay tuned here for Ken’s continuing Boeing, SpaceX, Orbital Sciences, commercial space, Orion, Curiosity, Mars rover, MAVEN, MOM and more planetary and human spaceflight news.
As we anxiously await the arrival of a potentially rich new meteor shower this weekend, its parent comet, 209P/LINEAR, draws ever closer and brighter. Today it shines feebly at around magnitude +13.7 yet possesses a classic form with bright head and tail. It’s rapidly approaching Earth, picking up speed every night and hopefully will be bright enough to see in your telescope very soon.
The comet was discovered in Feb. 2004 by the Lincoln Laboratory Near-Earth Asteroid Research (LINEAR) automated sky survey. Given its stellar appearance at the time of discovery it was first thought to be an asteroid, but photos taken the following month photos by Rob McNaught (Siding Spring Observatory, Australia) revealed a narrow tail. Unlike long period comets Hale-Bopp and the late Comet ISON that swing around the sun once every few thousand years or few million years, this one’s a frequent visitor, dropping by every 5.09 years.
209P/LINEAR belongs to the Jupiter family of comets, a group of comets with periods of less than 20 years whose orbits are controlled by Jupiter. When closest at perihelion, 209P/LINEAR coasts some 90 million miles from the sun; the far end of its orbit crosses that of Jupiter. Comets that ply the gravitational domain of the solar system’s largest planet occasionally get their orbits realigned. In 2012, during a relatively close pass of that planet, Jupiter perturbed 209P’s orbit, bringing the comet and its debris trails to within 280,000 miles (450,000 km) of Earth’s orbit, close enough to spark the meteor shower predicted for this Friday night/Saturday morning May 23-24.
This time around the sun, the comet itself will fly just 5.15 million miles (21 times the distance to the moon) from Earth around 3 a.m. CDT (8 hours UT) May 29 a little more than 3 weeks after perihelion, making it the 9th closest comet encounter ever observed. Given , you’d think 209P would become a bright object, perhaps even visible with the naked eye, but predictions call for it to reach about magnitude +11 at best. That means you’ll need an 8-inch telescope and dark sky to see it well. Either the comet’s very small or producing dust at a declining rate or both. Research published by Quanzhi Ye and Paul A. Wiegert describes the comet’s current dust production as low, a sign that 209P could be transitioning to a dormant comet or asteroid.
Fortunately, the moon’s out of the way this week and next when 209P/LINEAR is closest and brightest. Since we enjoy comets in part because of their unpredictability, maybe a few surprises will be in the offing including a brighter than expected appearance. The maps will help you track down 209P during the best part of its apparition. I deliberately chose ‘black stars on a white background’ for clarity in use at the telescope. It also saves on printer ink!
We’re grateful for the dust 209P/LINEAR carelessly lost during its many passes in the 19th and early 20th centuries. Earth is expected to pass through multiple filaments of debris overnight Friday May 23-24 with the peak of at least 100 meteors per hour – about as good as a typical Perseid or Geminid shower – occurring around 2 a.m. CDT (7 hours UT).
If it’s cloudy or you’re not in the sweet zone for viewing either the comet or the potential shower, astrophysicist Gianluca Masi will offer a live feed of the comet at the Virtual Telescope Project website scheduled to begin at 3 p.m. CDT (8 p.m. Greenwich Time) May 22. A second meteor shower live feed will start at 12:30 a.m. CDT (5:30 a.m. Greenwich Time) Friday night/Saturday morning May 23-24.
SLOOH will also cover 209P/LINEAR live on the Web with telescopes on the Canary Islands starting at 5 p.m. CDT (6 p.m. EDT, 4 p.m. MDT and 3 p.m. PDT) May 23. Live meteor shower coverage featuring astronomer Bob Berman of Astronomy Magazine begins at 10 p.m. CDT. Viewers can ask questions by using hashtag #slooh.
The International Space Station will have to look out for new debris from an exploded Russian rocket (NASA image)
Traveling through low-Earth orbit just got a little more dangerous; a drifting Russian Breeze M (Briz-M) rocket stage that failed to execute its final burns back on August 6 has recently exploded, sending hundreds of shattered fragments out into orbit.
Russia and the U.S. Defense Department (JFCC-Space) have stated that they are currently tracking 500 pieces of debris from the disintegrated Breeze M, although some sources are saying there are likely much more than that.
After a successful liftoff via Proton rocket on August 6 from the Baikonur Cosmodrome, the Breeze M upper stage’s engines shut off after only 7 seconds as opposed to the normal 18 minutes, leaving its fuel tanks filled with 10 to 15 tons of hydrazine and nitrogen tetroxide propellants. Its payloads, the Indonesian Telkom 3 and the Russian Express-MD2 communications satellites, were subsequently deployed into the wrong orbits as the Breeze M computer continued functioning.
Although originally expected to remain intact for at least another year, the rocket stage “violently disintegrated” on October 16. Evidence of the explosion was first observed by astronomer Robert McNaught at Australia’s Siding Springs Observatory, who counted 70 fragments visible within the narrow field-of-view telescope he was using for near-Earth asteroid observations.
The exact cause of the explosion isn’t known — it may have been sparked by an impact with another piece of space junk or the result of stresses caused by the Breeze M’s eccentric orbit, which varied in altitude from 265 to 5,015 kilometers (165 miles to 3,118 miles) with an inclination of 49.9 degrees.
This was the third such breakup of a partially-full Breeze M upper stage in orbit, the previous events having occurred in 2007 and 2010, and yet another Breeze M still remains in orbit after a failed burn in August 2011.
Most of the latest fragments are still in orbit at altitudes ranging from 250 to 5,000 km (155 to 3,100 miles), where they are expected to remain.
“Although some of the pieces have begun to re-enter, most of the debris will remain in orbit for an extended period of time.”
– Jamie Mannina, US State Department spokesperson
According to NASA the debris currently poses no immediate threat to the Space Station although the cloud is “believed not to be insignificant.” Still, according to a post on Zarya.com the Station’s course will periodically take it within the Breeze M debris cloud, and “will sometimes spend several days at a time with a large part of its orbit within the cloud.”
Source: RT.com and SpaceflightNow.com. Inset image: the Breeze M (Briz-M) upper stage which disintegrated on Oct. 16. (Khrunichev)