Project Starshot, an initiative sponsored by the Breakthrough Foundation, is intended to be humanity's first interstellar voyage. Credit: breakthroughinitiatives.org
For generations, human beings have fantasized about the possibility of finding extra-terrestrial life. And with our ongoing research efforts to discover new and exciting extrasolar planets (aka. exoplanets) in distant star systems, the possibility of actually visiting one of these worlds has received a real shot in the arm. Unfortunately, given the astronomical distances involved, not to mention the cost of mounting an expedition, doing so presents numerous significant challenges.
However, Russian billionaire Yuri Milner and the Breakthrough Foundation – an international organization committed to exploration and scientific research – is determined to mount an interstellar mission to Alpha Centauri, our closest stellar neighbor, in the coming years. With the backing of such big name sponsors as Mark Zuckerberg and Stephen Hawking, his latest initiative (named “Project Starshot“) aims to send a tiny spacecraft to the Alpha Centauri system to search for planets and signs of life.
We’re familiar with rockets, those controlled explosions that carry cargo and fragile humans to space. But are there some non-rocket ways we could get to space?
Want to go space? Get a rocket. Nothing else ever invented can release the tremendous amounts of energy in a controlled way to get you to orbit.
It all comes down to velocity. Right now, you’re standing still on the Earth. If you jump up, you’ll come right back down where you started. But if you had a sideways velocity of 10 meters/second and you jumped up, you’d land downrange a few meters… painfully. And if you were moving 7,800 meters per second sideways – and you were a few hundred kilometers up – you’d just orbit the Earth.
Gaining that kind of velocity takes rockets. These magical science thundertubes are incredibly expensive, inefficient and single-use. Imagine if you had to buy a new car for each commute. Just blasting a single kilogram to orbit typically costs about $10,000. When you buy a trip to space, only a few hundred k goes to the gas. Those millions of dollars mostly go into the cost of the rocket that you’re going to kick to the curb once you’re done with it.
SpaceX is one of the most innovative rocket companies out there. They’re figuring ways to reuse as much of the rocket as they can, slashing those pesky launch costs, which ruin what should otherwise be a routine trip to the Moon. Maybe in the future, rockets could be used hundreds or even thousands of times, like your car, or commercial airliners.
Is that the best we could do? Can’t we just ditch the rockets altogether? To get from the ground to orbit, you need to gain 7,800 meters per second of velocity. A rocket gives you that velocity through constant acceleration, but could you deliver that kind of velocity in a single kick?
How about a huge gun and just shoot things into orbit? You need to instantly impart enormous velocity to the vehicle. This creates thousands of times the force of gravity on the passengers. Anyone on board gets turned into a fine red coating distributed evenly throughout the cabin interior. You can only get away with this a few times before your guinea pig passengers get wise.
“Steward, there’s bone chips in my champagne!”
If you extend the length of the barrel of the gun over many kilometers, you can smooth out the force of acceleration that humans can actually withstand. This is the idea Startram proposed. They’re looking to build a track up the side of a mountain, and use electromagnetism to push a sled up to orbital velocity.
Different technologies to push a spacecraft down a long rail have been tested in several settings, including this Magnetic Levitation (MagLev) System evaluated at NASA’s Marshall Space Flight Center. Engineers have a number of options to choose from as their designs progress. Photo credit: NASA
This might sound far fetched, but many countries are using with maglev technology with trains and breaking speed records around the world. The Japanese recently pushed a maglev train to 603 kilometers per hour. This first version of Startram would cost $20 billion, and the tremendous forces would only work for any cargo being delivered in a non-living state, despite how it started out.
Even more expensive is the version with a 1500-kilometer track, able to spread the acceleration over a longer period and allow humans to fly into space, arriving safely in their original “non-paste” configuration.
There are a couple teeny technical hurdles. Such as a track 20 kilometers in altitude where projectiles exit the muzzle and venting atmosphere to prevent the shockwave that would tear the whole structure apart.
If it can be made to work, we could decrease launch costs down to $50/kilogram. Meaning a trip to the International Space Station could cost $5,000.
Another idea would be, unsurprisingly, lasers. I know it sounds like I’m making this up. Lasers can fix every future problem. They could track and blast launch vehicles with a special coating that vaporizes into gas when it’s heated. This would generate thrust like a rocket, but the vehicle would have to carry a fraction of the mass of traditional fuel.
You don’t even need to hit the rocket itself to create thrust. A laser could superheat air right behind the launch vehicle to create a tiny shockwave and generate thrust. This technology has been demonstrated with the Lightcraft prototype.
Artist’s conception of World View’s planned balloon mission some 19 miles (30 kilometers) up. Credit: World View Enterprises Inc.
What about balloons? It’s possible to launch balloons now that could get to such a high altitude that they’re above 90% of the Earth’s atmosphere. This significantly reduces the amount of atmospheric drag that rockets would need to complete the journey to space.
The space colonization pioneer Gerard K. O’Neill envisioned a balloon-based spaceport floating at the edge of space. Astronauts would depart from the spaceport, and require less thrust to reach orbit.
We’ve also talked about the idea of a space elevator. Stretching a cable from the Earth up to geostationary orbit, and carry payloads up that way. There are enormous hurdles to developing technology like that. There might not even be materials strong enough in the Universe to support the forces.
But a complete space elevator might not be necessary. It could be possible to use tethers rotating at the edge of space, which transfer momentum to spacecraft, raising them step by step to a higher velocity and eventually into orbit. These tethers lose velocity with each assist, but they could have some other propulsion system, like an ion drive, to restore their orbital velocity.
Future methods of accessing space will be a combination of some or all of these ideas together with traditional and reusable rockets. Balloons and air launch systems to decrease the rocket’s drag, electromagnetic acceleration to reduce the amount of fuel needed, and ground-based lasers to provide power and additional thrust and pew-pew noises. Perhaps with a series of tethers carrying payloads into higher and higher orbits.
It’s nice to know that engineers are working on new and better ways to access space. Rockets have made space exploration possible, but there are a range of technologies we can use to bring down the launch costs and open up whole new vistas of space exploration and colonization. I can’t wait to see what happens next.
What alternative methods of getting to space are you most excited about? Let us know your thoughts in the comments below.
It’s a long way out to the dwarf planet Pluto. So, just how fast could we get there?
Pluto, the Dwarf planet, is an incomprehensibly long distance away. Seriously, it’s currently more than 5 billion kilometers away from Earth. It challenges the imagination that anyone could ever travel that kind of distance, and yet, NASA’s New Horizons has been making the journey, and it’s going to arrive there July, 2015.
You may have just heard about this news. And I promise you, when New Horizons makes its close encounter, it’s going to be everywhere. So let me give you the advanced knowledge on just how amazing this journey is, and what it would take to cross this enormous gulf in the Solar System.
Pluto travels on a highly elliptical orbit around the Sun. At its closest point, known as “perihelion”, Pluto is only 4.4 billion kilometers out. That’s nearly 30 AU, or 30 times the distance from the Earth to the Sun. Pluto last reached this point on September 5th, 1989. At its most distant point, known as “aphelion”, Pluto reaches a distance of 7.3 billion kilometers, or 49 AU. This will happen on August 23, 2113.
I know, these numbers seem incomprehensible and lose their meaning. So let me give you some context. Light itself takes 4.6 hours to travel from the Earth to Pluto. If you wanted to send a signal to Pluto, it would take 4.6 hours for your transmission to reach Pluto, and then an additional 4.6 hours for their message to return to us.
Let’s talk spacecraft. When New Horizons blasted off from Earth, it was going 58,000 km/h. Just for comparison, astronauts in orbit are merely jaunting along at 28,000 km/h. That’s its speed going away from the Earth. When you add up the speed of the Earth, New Horizons was moving away from the Sun at a blistering 160,000 km/h.
Unfortunately, the pull of gravity from the Sun slowed New Horizons down. By the time it reached Jupiter, it was only going 68,000 km/h. It was able to steal a little velocity from Jupiter and crank its speed back up to 83,000 km/h. When it finally reaches Pluto, it’ll be going about 50,000 km/h. So how long did this journey take?
Artist’s conception of the New Horizons spacecraft at Pluto. Credit: Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute (JHUAPL/SwRI)
New Horizons launched on January 19, 2006, and it’ll reach Pluto on July 14, 2015. Do a little math and you’ll find that it has taken 9 years, 5 months and 25 days. The Voyager spacecraft did the distance between Earth and Pluto in about 12.5 years, although, neither spacecraft actually flew past Pluto. And the Pioneer spacecraft completed the journey in about 11 years.
Could you get to Pluto faster? Absolutely. With a more powerful rocket, and a lighter spacecraft payload, you could definitely shave down the flight time. But there are a couple of problems. Rockets are expensive, coincidentally bigger rockets are super expensive. The other problem is that getting to Pluto faster means that it’s harder to do any kind of science once you reach the dwarf planet.
New Horizons made the fastest journey to Pluto, but it’s also going to fly past the planet at 50,000 km/h. That’s less time to take high resolution images. And if you wanted to actually go into orbit around Pluto, you’d need more rockets to lose all that velocity. So how long does it take to get to Pluto? Roughly 9-12 years. You could probably get there faster, but then you’d get less science done, and it probably wouldn’t be worth the rush.
Are you super excited about the New Horizons flyby of Pluto? Tell us all about it in the comments below.
Artist's impression of the ALASA being deployed by a USAF fighter jet.
Credit: DARPA
For decades, the human race has been deploying satellites into orbit. And in all that time, the method has remained the same – a satellite is placed aboard a booster rocket which is then launched from a limited number of fixed ground facilities with limited slots available. This process not only requires a month or more of preparation, it requires years of planning and costs upwards of millions of dollars.
On top of all that, fixed launch sites are limited in terms of the timing and direction of orbits they can establish, and launches can be delayed by things as simple as bad weather. As such, DARPA has been working towards a new method of satellite deployment, one which eliminates rockets altogether. It’s known as the Airborne Launch Assist Space Access (ALASA), a concept which could turn any airstrip into a spaceport and significantly reduce the cost of deploying satellites.
What ALASA comes down to is a cheap, expendable dispatch launch vehicle that can be mounted onto the underside of an aircraft, flown to a high altitude, and then launched from the craft into low earth orbit. By using the aircraft as a first-stage, satellite deployment will not only become much cheaper, but much more flexible.
DARPA’s aim in creating ALASA was to ensure a three-fold decrease in launch costs, but also to create a system that could carry payloads of up to 45 kg (100 lbs) into orbit with as little as 24 hours’ notice. Currently, small satellite payloads cost roughly $66,000 a kilogram ($30,000 per pound) to launch, and payloads often must share a launcher. ALASA seeks to bring that down to a total of $1 million per launch, and to ensure that satellites can be deployed more precisely.
Artist’s concept of the ALASA second stage firing. Credit: DARPA
News of the agency’s progress towards this was made at the 18th Annual Commercial Space Transportation Conference (Feb 4th and 5th) in Washington, DC. Bradford Tousley, the director of DARPA’s Tactical Technology Office, reported on the progress of the agency’s program, claiming that they had successfully completed phase one, which resulted in three viable system designs.
Phase two – which began in March of 2014 when DARPA awarded Boeing the prime contract for development – will consist of DARPA incorporating commercial-grade avionics and advanced composites into the design. Once this is complete, it will involve launch tests that will gauge the launch vehicle’s ability to deploy satellites to desired locations.
“We’ve made good progress so far toward ALASA’s ambitious goal of propelling 100-pound satellites into low earth orbit (LEO) within 24 hours of call-up, all for less than $1 million per launch,” said Tousley in an official statement. “We’re moving ahead with rigorous testing of new technologies that we hope one day could enable revolutionary satellite launch systems that provide more affordable, routine and reliable access to space.”
These technologies include the use of a high-energy monopropellant, where fuel and oxidizer are combined into a single liquid. This technology, which is still largely experimental, will also cut the costs associated with satellite launches by both simplifying engine design and reducing the cost of engine manufacture and operation.
Artist’s concept of the ALASA vehicle deploying into orbit. Credit: DARPA
Also, the ability to launch satellites from runways instead of fixed launch sites presents all kinds of advantages. At present, the Department of Defense (DoD) and other government agencies require scheduling years in advance because the number of slots and locations are very limited. This slow, expensive process is causing a bottleneck when it comes to deploying essential space assets, and is also inhibiting the pace of scientific research and commercial interests in space.
“ALASA seeks to overcome the limitations of current launch systems by streamlining design and manufacturing and leveraging the flexibility and re-usability of an air-launched system,” said Mitchell Burnside Clapp, DARPA program manager for ALASA. “We envision an alternative to ride-sharing for satellites that enables satellite owners to launch payloads from any location into orbits of their choosing, on schedules of their choosing, on a launch vehicle designed specifically for small payloads.”
The program began in earnest in 2011, with the agency conducting initial trade studies and market/business case analysis. In November of that same year, development began with both system designs and the development of the engine and propellant technologies. Phase 2 is planned to last late into 2015, with the agency conducting tests of both the vehicle and the monopropellant.
Pending a successful run, the program plan includes 12 orbital launches to test the integrated ALASA prototype system – which is slated to take place in the first half of 2016. Depending on test results, the program would conduct up to 11 further demonstration launches through the summer of 2016. If all goes as planned, ALASA would provide convenient, cost-effective launch capabilities for the growing government and commercial markets for small satellites, which are currently the fastest-growing segment of the space launch industry.
And be sure to check out this concept video of the ALASA, courtesy of DARPA:
A girandola taking off during a night launch. Via Pyropage.com
Have you ever heard of a girandola? I had not until we came across this video — which is pretty incredible! This might be one of the most unique things I’ve ever seen.
Girandolas are flying horizontal wheels and are a favorite of pyrotechnicians.
But as rudimentary as the setting looks in the video, girandolas are high precision, finely tuned instruments. According a group of fireworks professionals called the Pennsylvania Organization of Recreational Chaos (PORC), “you must have every driver (rocket motor) fire at the same time and be precisely tuned in order for the girandola to fly. There is very little room for error or it will not fly.”
You can find more info about girandolas at the link above, or here and it looks like they are available for purchase here.
The world's greatest rockets, past, present and future. Credit and copyright: Alex Brown.
MOAR rockets! As a followup to our recent post about the Rockets of the World (to scale), here’s another graphic posted on imgur, created by Alex Brown. While the earlier graphic only included rockets that had flown, this one has rockets that are also in development, such as the SLS, Falcon Heavy and the Long March 9. It’s also a great look back at the history of rocket development, including the V-2 ballistic, England’s Black Arrow and Korolyov’v wide-body Sputnik. All are shown to scale, as compared with an average human being.
As noted, this graphic is as of the present, February 2015.
A graphics of all rockets that have flown, shown to scale. Credit: Tyler Skrabek
Inspired by a book and poster from 1995, titled “Rockets of the World,” graphic artist Tyler Skrabek has provided a new and updated “clean” look for his latest work.
“The ‘Rockets of the World’ poster emulates a 1960 style of drawing,” he said, “employing a consistent pallet across all rockets allowing for a distraction-free look at the size and power of the world’s greatest machines.”
Skrabek told Universe Today that he’s been working on this poster for 3 months, but he’s had the idea of creating it since 2012.
“The ‘Rockets of the World’ poster is something I put a lot of work into,” he said, “as it’s been my sole project for the last 3 months. Three years ago I was just interested in rockets and wanted to see how the most popular rockets stacked up against each other. But when I looked online to see if I could find a chart, all that existed were height comparisons using technical drawings with 3D renderings of newer rockets squished in. There just weren’t any posters that I could find that used consistent 3D full color renderings and that’s what I set out to create.”
He wanted an uncluttered look for his poster, and therefore used a set of rules to eliminate some rockets: The Rocket had to have more than 3 successful flights and each rocket had to be unique – no later versions from the same rocket family, such as the Soyuz.
Also, rocket wannabes didn’t make the cut … not yet anyway.
“Just to keep things tidy I choose not to include rockets that haven’t flown yet on the off-chance they don’t actually make it off the ground,” Tyler said on reddit. “But rest assured there will be a version that includes the Falcon 9 Heavy as soon as it does.”
A few months ago he created the “Rockets of Human Spaceflight” poster and posted it on reddit. He took suggestions from fellow redditors to create the final version, below. He used that poster as the impetus to continue the Rockets of the World poster.
Rockets of Human Spaceflight. Credit and copyright: Tyler Skrabek.
You can see the original “Rockets of the World” illustration from physics professor Peter Alway’s 1995 book “Rockets of the World” here.
Tyler said he’s always been passionate about space, spaceflight and human exploration in space.
“I find it fascinating that we as a society have the power to take a person, put that person inside a metal box on top of a cylinder filled with explosives and explore space,” he says on his website. “As an active member in space circles, I realized there was a lack of infographics that did a reasonable job of portraying comparisons between the various types of spacecraft while being visually appealing. I decided to research and develop a series of infographics to better explain this to the everyday person.”
We’re total litterbugs. Here on Earth, and out in space. What are some strategies that have been developed to clean up all that junk in space and make it safer to explore?
Humans are great at lots of things. We’ve built amazing landmarks, great works of art, and have a legacy of unique cultures and languages spanning the globe…
We’re also great at not cleaning up after ourselves. As if the oceanic garbage patches weren’t enough, humans are actually filling space with junk too.
That’s okay, right? Space might be infinite, and if you average the amount of stuff we know about versus the amount of space, there’s barely anything out there at all. Space can handle all that junk, right? Right? Sure it can! Space is just fine. Don’t you worry for one second about space. Space is big. Sure it’d kill us in a heartbeat, but it’s got no feelings to hurt! It’s just space!
Now I’m going to encourage you to be a little selfish, as this actually a problem for us. I know, it’s hard to believe that somehow, with our baked-in levels of neglect, we’re creating a global problem for us and future generations. I feel like this our thing now. It’s what defines us. Our littering up of space might prevent humans from ever being able to escape our planet again.
Here’s the deal. In the decades that humans have been launching stuff into space, nobody ever thought too hard about what we should do about our rockets and satellites after we’re done with them. It’s not like you can ever fill up space.
Astronomers are currently tracking 19,000 individual objects larger than 5 cm, and there are likely more than 300,000 objects smaller than 1 cm. All this stuff sticks around and continues to orbit the Earth. Over time debris collides with more debris, creating smaller and smaller pieces of space junk.
Some scientists are concerned that we might reach a point where this junk forms an impenetrable shield of shrieking metal around the Earth, that would tear apart any spacecraft that tries to leave our planet. I like to call this the “Spacelitter Singularity”. It’s an unstoppable cascade of collisions and chaos that converts the area around the Earth into a relentless blender of progressively smaller and smaller high velocity projectiles. Which would be bad.
Image plot of space junk. Image credit: NASA
So, how do we avoid that? How can we minimize the amount of space junk we throw into orbit? And how can get rid of the garbage that’s already out there? For starters, anyone launching stuff into space needs to minimize the amount of debris they generate. Rockets should maneuver back into the atmosphere to burn up. Astronauts need to keep track of their tools and gloves.
Engineers would also need to plan out what will happen to their spacecraft at the end of their lives. Instead of letting them just die, mission controllers need to be able to maneuver spacecraft into a safer parking orbit, or alternately, back into the atmosphere.
Something will need to be done with the space junk that’s already out there, chopping itself into smaller and smaller pieces. One idea is to have a one-up, one-down policy rule for companies. For every spacecraft they launch, they collect and de-orbit another spacecraft in roughly the same orbit. Or we could create a special junk removal spacecraft.
Space Junk. Image credit: Jonas Bendiksen/Eurasianet.org
These would use efficient ion engines to track and dock with pieces of space junk, collecting them together. Once the spacecraft had collected enough material, or run out of fuel, it could be safely de-orbited, or possibly transform into garbage truck Voltron.
The most awesome idea I’ve come across is to build a space-based laser system that could target and fire on pieces of space debris as they go by. Small pieces would be vaporized, and larger objects would be slowed down as the vaporization would act as a decelerating thrust, lowering their orbit. That’s right, one solution is to build a real life game of Asteroids.
Once again, a lack of forethought has a created a problem that will trouble future generations. Getting into space in the first place is super hard, and cleaning it up is going to take more work than we ever thought.
What do you think? How should we clean up space to make it safe for future generations of space faring humans? Tell us in the comments below.
And if you like what you see, come check out our Patreon page and find out how you can get these videos early while helping us bring you more great content!
The Challenger space shuttle a few moments after the rupture took place in the booster. Credit: NASA
What you see above is 32 minutes of something going wrong during each launch. While humanity has been launching things into space since the 1950s, you can see just how hard it is — over and over again. And when humans are riding aboard the rockets, the toll becomes more tragic.
According to the YouTube author of the video above, the vehicles shown include “V2, Vanguard TV3, Explorer S-1, Redstone 1, Titan I, Titan II, Titan IV, Atlas, Atlas-Centaur, N1, Delta, Delta III, Foton, Soyuz, Long March, Zenith, Space Shuttle Challenger, and more.”
Naturally, with each failure the engineers examine the systems and work to fix things for next time. A famous example is the Challenger shuttle explosion, which you can see about halfway through the video. There were multiple causes for the failure (human and technical), but one of them was an O-ring that failed in cold weather before the launch. NASA revised the launch rules and with contractors, made some changes to the booster rocket design, as a 2010 Air and Space Smithsonian article points out:
Freezing temperatures weakened an O-ring seal in a joint between two segments of the right booster. The weakness allowed hot gases to burn through the casing, causing the shuttle to break apart on ascent, which killed the seven-member crew. Two joints were redesigned with interlocking walls that had new bolts, pins, sensors, seals, and a third O-ring.
Still, launching is a risky business. That’s why it’s so important that engineers try to catch problems before they happen, and that as soon as a problem is seen, it’s fixed.
Sometimes you’ve just got to get away from it all. From your planet, your Solar System and your galaxy. If you’re looking to escape, you’ll need to know just what velocity it’ll take to break the surly bonds of gravity and punch the sky.
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