Technology Archives

February 13, 2014December 23, 2015 by David Dickinson

What to Wear? The History and Future of Spacesuits

The issue of “what to wear?” takes on an extra dimension of life and death when it comes to space travel. Upon exiting a spacecraft on a spacewalk, an astronaut becomes his very own personal satellite in orbit about the Earth and must rely on the flimsy layer of his suit to provide them with a small degree of protection from radiation and extreme fluctuations of heat and cold.

We recently had a chance to see the past, present and future of space suit technology in the Smithsonian Institutions’ touring Suited for Space exhibit currently on display at the Tampa Bay History Center in Tampa, Florida.

Tampa Bay History Center Director of Marketing Manny Leto recently gave Universe Today an exclusive look at the traveling display. If you think you know space suits, Suited for Space will show you otherwise, as well as give you a unique perspective on a familiar but often overlooked and essential piece of space hardware. And heck, it’s just plain fascinating to see the design and development of some of these earlier suits as well as videos and stills of astronauts at work – and yes, sometimes even at play – in them.

One of the highlights of the exhibit are some unique x-ray images of iconic suits from space travel history. Familiar suits become new again in these images by Smithsonian photographer Mark Avino, which includes a penetrating view of Neil Armstrong’s space suit that he wore on Apollo 11.

Space suits evolved from pressure suits developed for high-altitude flights in the 1950’s, and Suited for Space traces that progression. It was particularly interesting to see the depiction of Wiley Post’s 1934 suit, complete with steel cylindrical helmet and glass portal! Such early suits resembled diving bell suits of yore — think Captain Nemo in a chemsuit. Still, this antiquated contraption was the first practical full pressure suit that functioned successfully at over 13,000 metres altitude.

No suit that has been into space is allowed to tour due to the fragility of many historic originals that are now kept at the Smithsonian, though several authentic suits used in training during the U.S. space program are on display. We thought it was interesting to note how the evolution of the spacesuit closely followed the development of composites and materials through the mid-20^th century. You can see the progression from canvas, glass and steel in the early suits right up though the advent of the age of plastic and modern fabrics. Designs have flirted with the idea of rigid and semi-rigid suits before settling on the modern day familiar white astronaut suit.

Spacesuit technology has also always faced the ultimate challenge of protecting an astronaut from the rigors of space during Extra-Vehicular Activity, or EVA.

Cosmonaut Alexey Leonov performed the first 12 minute space walk during Voskhod 2 back in 1965, and NASA astronaut Ed White became the first American to walk in space on Gemini 4 just months later. Both space walkers had issues with over-heating, and White nearly didn’t make it back into his Gemini capsule.

Designing a proper spacesuit was a major challenge that had to be overcome. In 1962, Playtex (yes THAT Playtex) was awarded a contract to develop the suits that astronauts would wear on the Moon. Said suits had 13 distinct layers and weighed 35 kilograms here on Earth. The Playtex industrial division eventually became known as the International Latex Corporation or ILC Dover, which still makes spacesuits for ISS crewmembers today. It’s also fascinating to see some of the alternate suits proposed, including one “bubble suit” with arms and legs (!) that was actually tested but, thankfully, was never used.

These suits were used by astronauts on the Moon, to repair Hubble, build the International Space Station and much more. Al Worden recounts performing the “most distant EVA ever” on the return from the Moon in his book Falling to Earth. This record will still stand until the proposed asteroid retrieval mission in the coming decade, which will see astronauts performing the first EVA ever in orbit around Earth’s Moon.

And working in a modern spacesuit during an EVA is anything but routine. CSA Astronaut Chris Hadfield said in his recent book An Astronaut’s Guide to Life on Earth that “Spacewalking is like rock climbing, weightlifting, repairing a small engine and performing an intricate pas de deux – simultaneously, while encased in a bulky suit that’s scraping your knuckle, fingertips and collarbone raw.”

And one only has to look at the recent drama that cut ESA astronaut Luca Parmitamo’s EVA short last year to realize that your spacesuit is the only thin barrier that exists between yourself and the perils of space.

“We’re delighted to host our first Smithsonian Institution Travelling Exhibition Service (SITES) and we think that Florida’s close ties to NASA and the space program make it a great fit for us,” said Rodney Kite-Powell, the Tampa Bay History Center’s Saunders Foundation Curator of History.

Be sure to catch this fascinating exhibit coming to a city near you!

-And you can see these suits in action on the up and coming future EVAs for 2014.

-Here’s the schedule for Suited for Space Exhibit tour.

-Astronaut Nicole Stott (veteran of STS-128, -129, -133, & ISS Expeditions 20 and 21) will also be on hand at the Tampa Bay History Center on March 2014 (Date to be Announced) to present Suited for Space: An Astronaut’s View.

– Follow the Tampa Bay History Museum of Twitter as @TampaBayHistory.

February 12, 2014December 23, 2015 by David Dickinson

Space Station to Get a ‘Laser Cannon’

CATS in the laboratory. Credit: NASA/GSFC.

What’s a space station without a laser cannon?

The International Space Station will be getting its very own laser at the end of 2014. And unlike the planet-smashing capabilities of the Death Star of Star Wars fame, this laser will to be enlisted for the purpose of science.

It’s called CATS, and no, it isn’t the latest attempt to put feline astronauts in space. CATS stands for the Cloud Aerosol Transport System. The goal of CATS is to study the distribution of tiny particles of dust and air contaminants known as aerosols.

Developed by research scientist Matt McGill at NASA’s Goddard Space Flight Center in Greenbelt Maryland, CATS is slated to head to the International Space Station later this year on September 12th aboard SpaceX’s CRS-5 flight of the Dragon spacecraft. CATS will be installed on the Japanese Experiment Module-Exposed Facility (JEM-EF) and will demonstrate the utility of state-of-the-art multi-wavelength laser technology to study aerosol distribution and transport in the atmosphere.

Such knowledge is critical in understanding the path and circulation of aerosols and pollutants worldwide. When the Eyjafjallajökull volcano erupted in Iceland back in 2010, many trans-Atlantic flights were grounded as a precaution. These measures are necessary as several flights have suffered engine failures in the past due to encounters with volcanic ash clouds, such as the four engine failure of KLM Fight 867 in 1989 and the British Airways Flight 9 incident over Southeast Asia in 1982. Knowing where these dangerous ash clouds are is crucial to the safety of air travel.

The expanding ash cloud spewing from Iceland's Eyjafjallajökull volcano as seen from space in 2010. Credit: NASA. — The expanding ash cloud spewing from Iceland’s Eyjafjallajökull volcano as seen from space in 2010. Credit: NASA.

To accomplish this, CATS will emit 5,000 1 milliJoule laser pulses a second at the 1064, 532 and 355 nanometer wavelengths. This represents a vast improvement in power requirements and thermal capabilities over a similar instrument currently in service aboard the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) Earth remote sensing spacecraft.

And it’s that third 355 nanometer wavelength that will make CATS stand out from CALIPSO. This will also allow researchers to differentiate between particle size and measure the horizontal and vertical distribution of aerosol particles in the atmosphere. CATS will also be capable of measuring the number of individual photons being reflected back at it, which will provide a much better resolution and understanding of current atmospheric activity.

“You get better data quality because you make fewer assumptions, and you get, presumably, a more accurate determination of what kind of particles you’re seeing in the atmosphere,” McGill said in a recent press release.

The International Space Station also provides a unique vantage point for CATS. In a highly inclined 51.7 degree orbit, the station passes over a good swath of the planet on 16 orbits daily on a westward moving ground track that repeats roughly every three days. This will assure CATS has coverage over a large percentage of the planet, including known pollutant transport routes across the northern Pacific and down from Canada over the U.S. Great Lakes region.

While the first two lasers will operate in the infrared and visual wavelengths, said third laser will work in the ultraviolet. And while this will give CATS an enhanced capability, engineers also worry that it may also be susceptible to contamination. “If you get contamination on any of your outgoing optics, they can self-destruct, and then your system is dead. You end up with a very limited instrument lifetime,” McGill said.

Still, if CATS is successful, it may pave the way for larger, free-flying versions that will monitor long-range atmospheric patterns and shifts in climate due to natural and man-made activity. And the ISS makes a good platform to test pathfinder missions like CATS at low cost. “In our current budget-constrained environment, we need to use what we already have, such as the [station], to do more with less,” McGill said.

CALIPSO's LiDAR imaged from the ground by Gregg Hendry in 2008. Used with permission. — CALIPSO’s LiDAR imaged from the ground by Gregg Hendry in 2008. Used with permission.

The advent of a LiDAR system aboard the ISS has also generated a spirited discussion in the satellite tracking community concerning prospects for spotting CATS in operation from the ground. The CALIPSO LiDAR has been captured by ground spotters in the past. However, CALIPSO fires a much more powerful 110 milliJoule pulse at a rate of 20 times a second. Still, the lower power CATS system will be firing at a much faster rate, delivering a cumulative 5,000 milliJoules a second. CATS won’t be bright enough to show up on an illuminated pass of the ISS, but it just might be visible during darkened passes of the ISS through the Earth’s shadow. And, unlike CALLIPSO — which is part of the difficult to observe A-Train of Earth-observing satellites — the ISS passes in view of a majority of humanity. At very least, activity from CATS will be worth watching out for, and may well be seen either visually or photographically.

We’ll soon be adding CATS to the long list of outstanding science experiments being conducted aboard the International Space Station, and the sight of this “fully armed and operational battle station” may soon be coming to a dark sky site near you!

January 31, 2014April 26, 2016 by David Dickinson

From Webcam to Planetcam: Planetary Imaging on the Cheap

It’s a question we get often.

“What sort of gear did you use to capture that?” folks ask, imagining that I’m using a setup that required a second mortgage to pay for.

People are often surprised at the fact that I’m simply using a converted off-the-shelf webcam modified to fit into the eyepiece-holder of a telescope, along with freeware programs to control the camera, stack,and clean up images. And while there are multi-thousand dollar rigs available commercially that yield images that would have been the envy of professional observatories even a decade ago, you may just find that you have the gear lying around to start doing planetary and lunar photography tonight.

OK, I’ll admit: you do need a laptop and telescope, (things that we typically have “laying around” our house!) but these are the two priciest items on the list to get started. Living the vagabond life of a veteran, a teacher, and a freelance science writer assures that our preferred cameras for conversion are always in the double-digit dollar range.

Converted "Planetcam" installed on the 'scope. — Our first converted “Planetcam” installed on the ‘scope.

But converted webcam imaging is not new. We first read about the underground movement over a decade ago. Back in the day, amateur astrophotographers were hacking their Phillips Vesta and ToUcam Pro webcams with stunning results. Celestron, Meade and Orion later caught up to the times and released their own commercial versions for planetary imaging some years later.

A few freeware installations and the modification of a Logitech 3000 that I bought on rebate for 50$ later, and I was soon imaging planets that same night.

Just about any webcam will yield decent results, though the discontinued Phillips ToUcam Pro webcams are still the heavily sought after Holy Grail of webcam astrophotography. The modification simply consists of removing the camera lens (don’t do this with any camera that you don’t want to gut and void the warranty) and attaching a standard 1 ¼” eyepiece barrel in its place using cement glue.

For camera control, I use a program called K3CCDTools. This was freeware once upon a time, now the program costs $50 to install. I still find it well worth using, though I’ve been turned on to some equally useful programs out there that are still free. (more on that in a bit).

K3CCDTools will process your images from start to finish, but I find that Registax is great for post-image processing. Plus, you don’t want to waste valuable scope time processing images: I do the maximum number of video captures in the field, and then tinker with them later on cloudy nights.

Screen cap — A screen capture of K3CCD tools during a daytime alignment test. Note the focusing dialog (FFT) box to the right.

Stacking video captures enables you to “grab” those brief moments of fine atmospheric seeing. Many astrophotographers will manually select the best frames from thousands one by one, but I’ll have to admit we’re often impatient and find the selection algorithm on Registax does an acceptable job of selecting the top 10% of images in a flash.

And like Photoshop, a college course could be taught around Registax. Don’t be intimidated, but do feel free to experiment! After stacking and optimizing, we find the true power in making the images “pop” often lies in the final step, known as wavelet processing. A round of sharpening and contrast boosting in Photoshop can also go a long way, just remember that the goal is to apply the minimum to get the job done, rather than looking unnatural and over-processed.

Photos by author — A photo mosaic of the historic Mars opposition of 2003.

At the eyepiece, the first target hurdle is object acquisition. A standard webcam can go after bright targets such as the Moon, the Sun (with the proper filter) planets, and bright double stars. We’ve even nabbed the International Space Station with our rig using a low-tech but effective tracking method. Your field of view, however, will typically be very narrow; my webcam coupled to a Celestron C8” Schmidt-Cassegrain typically yields a field of view about 10’ on a side. You’ll want to center the object in the eyepiece at the highest power possible, then plop the camera in place.

The next battle is centering and focusing the object on the screen. An out-of-focus planet scatters light: tweaking the focus back and forth sometimes reveals the silvery “doughnut” of the planet lurking just out of view.

From there, you’ll want the object in as razor sharp a focus as possible. K3CCDTools has a great feature for this known as a Fine Focusing Tool (FFT). Some observers also using focusing masks, which can also be easily built — remember, were being cheapskates! — out of cardboard. Be sure those reflector mirrors are properly collimated as well.

Don’t be surprised if the planet initially looks over-saturated. You’ll want to access the manual controls of via the camera software to take the brightness, contrast and color saturation down to acceptable levels. I typically shoot at about 15 frames a second. Fun Fact: the “shutter speed” of the dark adapted “Mark 1 human eyeball” is generally quoted around 1/20^th of a second, slower than you’d think!

Note: all those thousands of frames of video go somewhere… be sure to occasionally clean them off your hard-drive, as it will swiftly fill up!

When you image makes a big difference as well. The best time to shoot an object is when it transits the local north-south meridian and is at its highest point above the horizon. The reason for this is that you’re looking through the thinnest possible cross-section of the often turbulent atmosphere.

Universe Today reader Scott Chapman of Montpelier, Virginia also recently shared with us his exploits in planetary webcam imaging and his technique:

A webcam image of the Mare Crisium region on the Moon. Credit-Scott Chapman

“Recently, while looking for an affordable basic telescope, to see if I really had any interest in astronomy, searches and reviews led me to purchase a 70mm refractor. The last thing on my mind was that I could expect to take any pictures of what I might see.

Previously, I had assumed that the only way to take even basic pictures of sky objects was with equipment that was way out of my price range. Imagine my surprise to learn that I could use a simple webcam that I already had sitting around!”

Like many of us mere mortal budget astrophotographers, Scott’s goal was great images at low cost. He also shared with us the programs he uses;

–SharpCap2: For capturing .avi video files from the webcam connected to the telescope.

–VirtualDub: For shortening the .avi video.

–PIPP: For optimization of stacked images.

–AutoStakkert2: Selects and stacks the best frames into a single .tiff file using a simple 3-step process. Scott notes that its “MUCH easier for a beginner to use than Registax!”

-Registax6: The latest version of the software mentioned above.

–JPEGView: For final cropping and file conversion. (I sometimes also use ye ole Paint for this).

Even after a decade of planetary imaging, some of these were new to us as well, a testament to just how far the technique has continued to evolve. Astrophotography and astronomy are lifelong pursuits, and we continue to learn new things every day.

The current camera I’m shooting with is a Logitech c270 that I call my “Wal-Mart 20$ Blue Light Special.” (Yes, I know that’s Kmart!) Lots of discussion forums exist out there as well, including the QuickCam and Unconventional Imaging Astronomy Group (QCUIAG) on Yahoo!

Some observers have even taken to gutting and modifying their webcams entirely, adding in cooling fans, more sensitive chips, longer exposure times and more.

All great topics for a future post. Let us know of your trials and triumphs in webcam planetary photography!

-Watch Dave Dickinson pit his 20$ webcam against multi-thousand dollar rigs weekly in the Virtual Star Party.

-Be sure to send those webcam pics in to Universe Today!

January 17, 2014December 23, 2015 by Nancy Atkinson

Compare the Space Station’s Internet Speed with Yours

The International Space Station as seen from the crew of STS-119. Credit: NASA

We now take it for granted that astronauts on the International Space Station can tweet and post things on Facebook and G+ live from space, but it wasn’t always so. Before January of 2010, any emails, news, or Twitter messages were sent to and from the ISS in uplink and downlink packages, so for example, Twitter messages from the astronauts were downlinked to mission control in Houston, and someone there posted them on the astronauts’ Twitter accounts. But now they have “live” internet. However, as you can imagine, there are no fiberoptic cables hooking up to the ISS, so the internet speeds aren’t blazing fast. Find out how fast in this latest video update from NASA’s Space to Ground, a weekly update on what’s happening aboard the ISS.

January 6, 2014December 23, 2015 by Nancy Atkinson

Internet Search Yields No Evidence of Time Travelers

Comet ISON was used in a search for time travelers. NASA’s Hubble Space Telescope provides a close-up look of Comet ISON (C/2012 S1), as photographed on April 10. Credit: NASA, ESA, J.-Y. Li (Planetary Science Institute), and the Hubble Comet ISON Imaging Science Team.

You can find anything on the internet, right? A new study reveals, however, that you can’t find evidence of time travelers on the internet. Credible time travelers, that is.

The study was conducted by astrophysicist Robert Nemiroff who is part of the Astronomy Picture of the Day (APOD) team, along with some of his students from Michigan Technological University.

They did three separate types of searches, and developed a search strategy based on what they call “prescient knowledge.” They looked for discussions on social media and various websites where there might be evidence of a mention of something or someone before people should have known about it. If they were able to find evidence of that, it could indicate that whoever wrote it had traveled from the future.

They selected search terms relating to two recent phenomena, Pope Francis and Comet ISON, and began looking for references to them before they were known to exist.

First, they looked for specific terms on Twitter, then secondly looked for “prescient” inquiries submitted to a search engine, and the third search involved a request for a direct Internet communication, either by email or tweet, pre-dating to the time of the inquiry.

The team used a variety of search engines, such as Google and Bing, and combed through Facebook and Twitter.

Their results? “No time travelers were discovered,” says the abstract of their paper.

“In our limited search we turned up nothing,” Nemiroff said in a press release. “I didn’t really think we would. But I’m still not aware of anyone undertaking a search like this. The Internet is essentially a vast database, and I thought that if time travelers were here, their existence would have already come out in some other way, maybe by posting winning lottery numbers before they were selected.”

So far, no lottery winners have confessed to using time travel to make their winnings.

In the case of Comet ISON, there were no mentions before it was discovered in September 2012. They discovered only one blog post referencing a Pope Francis before Jorge Mario Bergoglio was elected head of the Catholic Church on March 16, but it seemed more accidental than prescient.

In the third part of their search, the researchers created a post in September 2013 asking readers to email or tweet one of two messages on or before August 2013: “#ICanChangeThePast2” or “#ICannotChangeThePast2.”

No replies have been given … yet.

And just in case you’re wondering credible time travelers do not include the two “chrononauts” who said they time traveled with a young Barack Obama.

Nemiroff and physics graduate student Teresa Wilson will present their findings today, Monday, Jan. 6, at the American Astronomical Society meeting in Washington, DC.

December 11, 2013December 23, 2015 by Nancy Atkinson

Turn on Your Heart Light and Meet NASA’s “Superhero” Robot

A concept drawing of what eventually became Valkyrie, Johnson Space Center's entry in the DARPA Robotics Challenge. Credit: NASA, via DARPA.

Here’s a new DARPA-inspired, NASA-built robot, complete with a glowing NASA Meatball in its chest, reminiscent of ET’s heart light. The robot’s name is Valkyrie and she was created by a team at the Johnson Space Center as part of the DARPA Robotics Challenge, a contest designed to find the life-saving robot of the future. While NASA’s current robot — Robonaut 2 – is just now getting a pair of legs, “Val” (officially named “R5″ by NASA) is a 1.9 meter tall, 125 kilogram, (6-foot 2-inch, 275-pound) rescue robot that can walk over multiple kinds of terrain, climb a ladder, use tools, and even drive.

According to an extensive article about the new robot in IEEE Spectrum, “This means that Valkyrie has to be capable of operating in the same spaces that a person would operate in, under the control of humans who have only minimal training with robots, which is why the robot’s design is based on a human form.”

Why is NASA building more robots? The thinking is that NASA could send human-like robots to Mars before they send humans. Right now, Valkyrie is not space-rated, but the team at JSC is just getting started.

She’s loaded with cameras, LIDAR, SONAR, is strong and powerful, and is just a great-looking robot.

“We really wanted to design the appearance of this robot to be one that was, when you saw it you’d say, wow, that’s awesome.” Nicolaus Radford, Project and Group Lead at the Dexterous Robotics Lab and JSC.

November 21, 2013December 23, 2015 by David Dickinson

NASA Halts Work on its New Nuclear Generator for Deep Space Exploration

MSL's MMRTG in the laboratory. (Credit: NASA).

Another blow was dealt to deep space exploration this past weekend. The announcement comes from Jim Green, NASA’s Planetary Science Division Director. The statement outlines some key changes in NASA’s radioisotope program, and will have implications for the future exploration of the outer solar system.

An Advanced Stirling Converter prototype in the laboratory. (Credit: NASA).

We’ve written about the impending plutonium shortage and what it means for the future of spaceflight, as well as the recent restart of plutonium production. NASA is the only space agency that has conducted missions to the outer planets — even the European Space Agency’s Huygens lander had to hitch a ride with Cassini to get to Titan — and plutonium made this exploration possible. Continue reading “NASA Halts Work on its New Nuclear Generator for Deep Space Exploration”

November 21, 2013December 23, 2015 by Nancy Atkinson

The Challenges of Lasers in Space

Artist concept of a solar sail demonstration mission that will use lasers for navigation. Credit: NASA.

Since the beginning of the space age, radio waves have been used for communication with spacecraft. But last month, NASA’s Lunar Laser Communication Demonstration (LLCD) made history by using a pulsed laser beam to transmit data over the 385,000 km (239,000 miles) between the Moon and Earth at a record-breaking download rate of 622 megabits per second (Mbps). This was NASA’s first system for two-way communication using a laser instead of radio waves. In our previous article today, we described how NASA will test out the Optical PAyload for Lasercomm Science (OPALS) on the International Space Station to demonstrate how videos can be beamed to Earth via laser beam.

What are the challenges in testing out an entirely new way of doing communications and other systems like navigation using lasers in space?

Don Cornwell, LLCD manager, discusses the challenges and successes they’ve had so far in this new video:

“The big change is the ability to do it by light, because the data rates that we’ve now done are just the opening shot, so to speak,” Cornwell said. “Radio communications systems have served us very well for the past 50 years but they are starting to run out of bandwidth, so in other words because of the frequency they use you can only modulate a certain portion of that frequencies and unless you move to higher frequencies – and light is a higher frequency than radio waves– you can’t squeeze a lot more bandwidth out, but the light systems in space, … we’ve now opened up a whole new field where we’re getting started , but the sky’s the limit regarding how much we can do there.”

Using lasers will allow for increased bandwidth for image resolution and 3-D video transmission from deep space, as well as allowing for tele-operation for long distances, such as from the Earth to the Moon.

LLCD is a short-duration experiment and the precursor to NASA’s long-duration demonstration, the Laser Communications Relay Demonstration (LCRD). LCRD is a part of the agency’s Technology Demonstration Missions Program, which is working to develop crosscutting technology capable of operating in the rigors of space. It is scheduled to launch in 2017.

Meanwhile, NASA has three other laser technology demonstration missions in the offing, likely launching in 2015 and 2016. One is a solar sail demonstration will enable propellantless laser in-space navigation for missions such as advanced geostorm warning, economic orbital debris removal, and deep space exploration.

November 21, 2013December 23, 2015 by Elizabeth Howell

Pew! Pew! Laser On The Space Station Will Beam Video To Earth

Artist's conception of an astronaut installing the Optical PAyload for Lasercomm Science (OPALS) experiment, which will be installed on the Earth-facing side of the International Space Station. Credit: NASA

Videos will beam to Earth on a laser beam in a technology demonstration coming to the International Space Station soon, says NASA’s Jet Propulsion Laboratory.

The Optical PAyload for Lasercomm Science (OPALS) plans to move videos from space to an Optical Communications Telescope Laboratory in Wrightwood, Calif. Each demonstration test will last about 100 seconds, while the station and the ground receiver can “see” each other.

While the experiment sounds awesome for sending back “home videos” from space, NASA is more touting it as a boon for transferring loads of scientific data back to Earth.

“The scientific instruments in near-Earth and deep-space missions increasingly require higher communication rates to transmit their gathered data back to Earth or to support high-data-rate applications (e.g., high-definition video streams),” stated the OPALS webpage at NASA’s Jet Propulsion Laboratory.

“Optical communications (also referred to as ‘lasercomm’) is an emerging technology wherein data is modulated onto laser beams, which offers the promise of much higher data rates than what is achievable with radio-frequency (RF) transmissions.”

How the Optical PAyload for Lasercomm Science (OPALS) experiment will work on the International Space Station. Credit: NASA

The experiment page (last updated in May) says it is intended to work for about a year, with the current Expedition 37/38 and forthcoming 39/40 crews. That said, it appears the payload is not aboard station yet.

A July update from NASA said the SpaceX Dragon spacecraft is supposed to ferry OPALS to space. There hasn’t been a Dragon flight since that time, but SpaceX is listing one more for 2013 on its launch manifest.

Diagram of the Optical PAyload for Lasercomm Science (OPALS) experiment. It includes three elements: (1) a sealed container that includes the laser, a power board and avionics (2) an optical gimbal transceiver that has an uplink camera, and laser collimater for downlink (3) a Flight Releasable Attachment Mechanism (FRAM), a mechanical and electrical link to the International Space Station and launch vehicle. Credit: NASA

Laser communication hit headlines earlier this fall when the NASA Lunar Atmosphere and Dust Environment Explorer (LADEE) sent a packet of information by laser from the moon, breaking records in terms of download rate (622 megabits per second).

October 10, 2013January 20, 2021 by Fraser Cain

What is a Space Elevator?

Almost every part of a rocket is destroyed during the launch and re-entry into the Earth’s atmosphere. This makes spaceflight really expensive. Rocket delivery of even a single kilogram into orbit costs tens of thousands of dollars. But what if we could just place our payloads directly into orbit, and didn’t need a rocket at all?

This is the idea of a space elevator, first envisioned by the Russian rocket scientist Konstantin Tsiolkovsky in 1895. Tsiolkovsky suggested building a tower all the way up to geostationary orbit, this is the point where a satellite appears to hang motionless in the sky above the Earth. If you could carry spacecraft all the way up to the top, and release them from that tower they’d be in orbit, without the expense of a discarded rocket. A fraction more energy and they’d be traveling away from the Earth to explore the Solar System.

The major flaw with this idea is that the entire weight of the tower would be compressing down on every part below. And there’s no material on Earth, or in the Universe, that can handle this kind of compressive force. But the idea still makes sense.

Newer thinking about space elevators propose using a cable, stretched out beyond geostationary orbit. Here the outward centripetal force counters the force of gravity, keeping the tether perfectly balanced. But now we’re dealing with the tensile strength of a cable tens of thousands of kilometers long.

Imagine the powerful forces trying to tear it apart. Until recently, there was no material strong enough to withstand those forces, but the development of carbon nanotubes has made the idea more possible.

How would you build a space elevator? The most reasonable idea would be to move an asteroid into geostationary orbit – this is your counterbalance. A cable would then be manufactured on the asteroid, and lowered down towards the Earth.

As the cable extends down, the asteroid is orbited further from the Earth, keeping everything in balance. Finally, the cable reaches the Earth’s surface and is attached to a ground station.

Artists concept of a space elevator. Credit: Caltech

Solar powered machines are attached to the space elevator and climb up from the surface of the Earth, all the way to geostationary orbit. Even traveling at a speed of 200 km/hour, it would take the climber almost 10 days to make the journey from the surface to an altitude of 36,000 kilometers. But the cost savings would be dramatic.

Currently, rockets cost about $25,000 per kilogram to send a payload to geostationary orbit. A space elevator could deliver the same payload for $200 per kilo.

Obviously there are risks associated with a megastructure like this. If the cable breaks, portions of it would fall to Earth, and humans traveling up in the elevator would be exposed to damaging radiation in the Earth’s Van Allen belts.

Building a space elevator from Earth is at the very limits of our technology. But there are places in the Solar System which might make much more useful places to build elevators.

The Moon, for example, has a fraction of the Earth’s gravity, so an elevator could operate there using commercially available materials. Mars might be another great place for a space elevator.

Whatever happens, the idea is intriguing. And if anyone does build a space elevator, they will open up the exploration of the Solar System in ways that we can’t even imagine.