One Method For Removing Future Space Junk

When sending satellites into space, the idea is to place them into as stable an orbit as possible in order to maximize both the time the satellite is useful and the economics of sending it there in the first place. This tends to become rather untenable as the amount of space junk continues to pile up for all but the lowest of orbits, but a team at Brown University recently tested a satellite that might help solve this problem, at least for future satellite deployments.

The main test of this satellite was its drag sail, which increases its atmospheric drag significantly and reduces its spaceflight time to around five years. This might make it seem like a problem from an economics standpoint, as it’s quite expensive to build satellites and launch them into space, but this satellite solves these problems by being both extremely small to minimize launch costs, and also by being built out of off-the-shelf components not typically rated for spaceflight. For example, it gets its power solely from AA batteries and uses an Arduino for its operation and other research.

The satellite is currently in orbit, and has already descended from an altitude of 520 km to 470 km. While it won’t help reduce the existing amount of debris in orbit, the research team hopes to demonstrate that small satellites can be affordable and economically feasible without further contributing to the growing problem of space junk. If you’re looking to launch your own CubeSat one day, take a look at this primer which goes over most of the basics.

Hackaday Links Column Banner

Hackaday Links: January 8, 2023

Something odd is afoot in the mountains around Salt Lake City, Utah, at least according to local media reports of remote radio installations that have been popping up for at least the past year. The installations consist of a large-ish solar panel, a weatherproof box full of batteries — and presumably other electronics, including radios — and a mast bearing at least one antenna. Local officials aren’t quite sure who these remote setups belong to or what they’re intended to do, but the installations obviously represent a huge investment in resources.

The one featured in the story was located near the summit of Twin Peaks, which is about 11,000 feet (3,300 meters) in elevation, which with that much gear was probably a hell of a hike. Plus, the owner took great pains to make sure the site would withstand the weather, with antenna mast guy wires that must have required lugging a pretty big drill up with them. There aren’t any photos of the radios in the enclosure, but one photo shows a 900-MHz LORA antenna, while another shows what appears to be a panel antenna, perhaps pointing toward another site. So maybe a LORA mesh network? Some comments in the Twitter thread show most people are convinced this is a Helium crypto mining rig, but the Helium Explorer doesn’t show any hotspots listed in that area. Either way, the owners are out of luck, since their gear is being removed if it’s on public land.

Continue reading “Hackaday Links: January 8, 2023”

CAPSTONE: The Story So Far

After decades of delays and false starts, NASA is finally returning to the Moon. The world is eagerly awaiting the launch of Artemis I, the first demonstration flight of both the Space Launch System and Orion Multi-Purpose Crew Vehicle, which combined will send humans out of low Earth orbit for the first time since 1972. But it’s delayed.

While the first official Artemis mission is naturally getting all the attention, the space agency plans to do more than put a new set of boots on the surface — their long-term goals include the “Lunar Gateway” space station that will be the rallying point for the sustained exploration of our nearest celestial neighbor.

But before launching humanity’s first deep-space station, NASA wants to make sure that the unique near-rectilinear halo orbit (NRHO) it will operate in is as stable as computer modeling has predicted. Enter the Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment, or CAPSTONE.

CAPSTONE in the clean room prior to launch.

Launched aboard an Electron rocket in June, the large CubeSat will hopefully become the first spacecraft to ever enter into a NRHO. By positioning itself in such a way that the gravity from Earth and the Moon influence it equally, maintaining its orbit should require only periodic position corrections. This would not only lower the maintenance burden of adjusting the Lunar Gateway’s orbit, but reduce the station’s propellant requirement.

CAPSTONE is also set to test out an experimental navigation system that uses the Lunar Reconnaissance Orbiter (LRO) as a reference point instead of ground-based stations. In a future where spacecraft are regularly buzzing around the Moon, it will be important to establish a navigation system that doesn’t rely on Earthly input to operate.

So despite costing a relatively meager $30 million and only being about as large as a microwave oven, CAPSTONE is a very important mission for NASA’s grand lunar aspirations. Unfortunately, things haven’t gone quite to plan so far. Trouble started just days after liftoff, and as of this writing, the outcome of the mission is still very much in jeopardy.

Continue reading “CAPSTONE: The Story So Far”

SpinLaunch And The History Of Hurling Stuff Into Space

It’s fair to say that there’s really no phase of spaceflight that could be considered easy. But the case could be made that the most difficult part of a spacecraft’s journey is right at the very beginning, within the first few minutes of flight. At this point the vehicle’s booster rocket will be fighting with all its might against its own immense propellant-laden mass, a battle that it’s been engineered to win by the smallest of margins. Assuming the balance was struck properly and the vehicle makes its way off of the launch pad, it will still need to contend with the thick sea-level atmosphere as it accelerates, a building dynamic pressure that culminates with a point known as “Max q” — the moment where the air density imposes the maximum structural load on the rocket before quickly dropping off as the vehicle continues to ascend and the atmosphere thins.

Air-launched rockets avoid flying through dense sea level air.

While the vast majority of rocket launches have to contend with the realities of flying through the lower atmosphere, there are some exceptions. By launching a rocket from an aircraft, it can avoid having to power itself up from sea level. This allows the rocket to be smaller and lighter, as it doesn’t require as much propellant nor do its engines need to be as powerful.

The downside of this approach however is that even a relatively small rocket needs a very large aircraft to carry it. For example, Virgin Orbit’s LauncherOne rocket must be carried to launch altitude by a Boeing 747-400 airliner in order to place a 500 kg (1,100 lb) payload into orbit.

But what if there was another way? What if you could get all the benefits of starting your rocket from a higher altitude, without the cost and logistical issues involved in carrying it with a massive airplane? It might sound impossible, but the answer is actually quite simple…all you have to do it throw it hard enough.

Continue reading “SpinLaunch And The History Of Hurling Stuff Into Space”

Pinning Tails On Satellites To Help Prevent Space Junk

Low Earth orbit was already relatively crowded when only the big players were launching satellites, but as access to space has gotten cheaper, more and more pieces of hardware have started whizzing around overhead. SpaceX alone has launched nearly 1,800 individual satellites as part of its Starlink network since 2019, and could loft as many as 40,000 more in the coming decades. They aren’t alone, either. While their ambitions might not be nearly as grand, companies such as Amazon and Samsung have announced plans to create satellite “mega-constellations” of their own in the near future.

At least on paper, there’s plenty of room for everyone. But what about when things go wrong? Should a satellite fail and become unresponsive, it’s no longer able to maneuver its way out of close calls with other objects in orbit. This is an especially troubling scenario as not everything in orbit around the Earth has the ability to move itself in the first place. Should two of these uncontrollable objects find themselves on a collision course, there’s nothing we can do on the ground but watch and hope for the best. The resulting hypervelocity impact can send shrapnel and debris flying for hundreds or even thousands of kilometers in all three dimensions, creating an extremely hazardous situation for other vehicles.

One way to mitigate the problem is to design satellites in such a way that they will quickly reenter the Earth’s atmosphere and burn up at the end of their mission. Ideally, the deorbit procedure could even activate automatically if the vehicle became unresponsive or suffered some serious malfunction. Naturally, to foster as wide adoption as possible, such a system would have to be cheap, lightweight, simple to integrate into arbitrary spacecraft designs, and as reliable as possible. A tall order, to be sure.

But perhaps not an impossible one. Boeing subsidiary Millennium Space Systems recently announced it had successfully deployed a promising deorbiting device developed by Tethers Unlimited. Known as the Terminator Tape, the compact unit is designed to rapidly slow down an orbiting satellite by increasing the amount of drag it experiences in the wispy upper atmosphere.

Continue reading “Pinning Tails On Satellites To Help Prevent Space Junk”

CubeSat For Under $1000?

Want to build your own CubeSat but have been put off by the price? There may be a solution in the works — [RG Sat] has challenged himself to design and build one for less than $1,000. (Video, embedded below.)

He begins by doing a survey of available low-cost options in the first video, and finds there isn’t a complete package for less than $10,000. By the time you added all necessary “options”, the final tally would probably be well over $20,000.

His idea isn’t just a pipe dream, either. In the the fifteen months since he began the project, [RG Sat] has designed and built the avionics and electrical power system circuit boards, and is currently testing his sun tracker design. Software is written in Rust, just because he wants to learn something new. You can check out the¬†hardware and software design files on the project’s GitHub repositories, if you are inclined to build one yourself.

[RG Sat] lays out a compelling case, but we wonder if there’s a major gotcha lurking in the dark somewhere. In fact, [RG Sat] himself asks the question, “where do these high costs come from?” Our first instinct is to point the finger at qualifying parts for space and/or testing. But if you don’t care about satellite longevity or failure rates, then maybe [RG Sat] is onto something here.

Stepping back and looking at the big picture, however, the price of a CubeSat can be a drop in the bucket when compared to the launch costs, unless you’ve got a free ride. Is hardware the best place to focus cost reduction efforts? ¬†Regardless, [RG Sat]’s project is bound to provide interesting and useful results whether he succeeds in his goal or confirms that indeed you need $10,000 to build a CubeSat. We’ll be following his progress with interest.

We’ve written about open source CubeSats before, and also a port-mortem analysis of a failed mission that contains some good lessons. Thanks to [Jeremy Grosser] for the tip.

 

Hello From The NearSpace

A key challenge for any system headed up into the upper-atmosphere region sometimes called near space is communicating back down to the ground. The sensors and cameras onboard many high altitude balloons and satellites aren’t useful if the data they collect can’t be retrieved. Often times, custom antennas or beacons are added to help. Looking at the cost and difficulty of the problem, [arko] and [upaut] teamed up to try and make a turn-key solution for any near-space enthusiast by building CUBEX, a wonderful little module with sensors and clever radio that can be easily reused and repurposed.

CUBEX is meant as a payload for a high-altitude balloon with a camera, GPS, small battery, solar cell, and the accompanying power management circuits. The clever bit comes in the radio back down. By using the 434.460 Mhz band, it can broadcast around a hundred miles at 10mW. The only hardware to receive is a radio listener (a cheap RTL USB stick works nicely). Pictures and GPS coordinates stream down at 300 baud.

Their launch was quite successful and while they didn’t catch a solar eclipse, their balloon reached an impressive 33698m (110,560ft) while taking pictures. Even though it did eventually splashdown in the Pacific Ocean, they were able to enjoy a plethora of gorgeous photos thanks to their easy and cost-effective data link.

Continue reading “Hello From The NearSpace”