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Suolucidir t1_jcz19jr wrote

It is testing the deployable yellow drag net material pictured at the bottom of the device.

Compared with other small objects released during the same mission, this object is set to re-enter Earth's atmosphere about 5x faster(5 years instead of 25 years) due to that lightweight yellow drag material.

It won't remove any other space junk with it, but it is testing the idea that we can use cheap drag net material to more quickly return space junk to earth.

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threebillion6 t1_jcza4hr wrote

That's exactly what we need. Something to deorbit faster. Otherwise we're gonna be sending UP more things to bring more things down. Seems like a massive waste to send something up just to bring stuff down.

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Due_Start_3597 t1_jcze5g5 wrote

I always thought satellites had some little thrusters on them with some nominal way to make micro-adjustments?

I figured if they wanted to deorbit them, they could be by making "deorbit trajectories"?

Is that not true?

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GallantChaos t1_jczf6o4 wrote

I see two possibilities for why this may not be:

  1. Those thrusters may be necessary for collision avoidance during the deorbit phase. (to prevent hitting in-service satellites)

  2. The thrusters are used and depleted to keep the satellites in orbit - and thus in service - as long as possible.

Adding a parachute like this may help increase drag and can be deployed with little additional cost/mass.

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burnbabyburn11 t1_jd1z0zl wrote

Gyroscopes bro

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Zkootz t1_jd2cudw wrote

What would a gyro do more than rotate the satellite?

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Mackie_Macheath t1_jd2j9hh wrote

Orient the satellite different so the chute creates less drag or move even over the long trajectory slightly sidewards.

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Thelastosirus t1_jd63mfo wrote

You are literally describing the Lightsail satellite experiment that went into orbit awhile back. It's meant to increase orbit using the pressure from the sun based off the angle of the sail, sort of like a wind sail. Just to keep you from wondering it actually works!

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TekguyTheRed t1_jd0dw73 wrote

That's partly true but there's more to it than that.

Satellites larger than a cube sat tend to have thrusters for orbital trajectory maintenance and to desaturate gyroscopes. But what tends to happen is that since they cost so much to get onto orbit you generally want to maximise the operational life of the satellite by using as much of your fuel as possible to stay up. So most operators just use all the fuel and leave nothing to de-orbiting. And if you put it into a orbit above 600km the time taken to naturally decay due to atmospheric and orbital perturbations becomes long, 10+ years where the satellite is uncontrollable and is a hazard.

New regulations are being introduced to reduce this sort of issue but it's more of a guideline than a law so companies with a commercial interest tend to ignore it.

What this development is really good for is small cubesats which make up the bulk of satellites launched these day by over a order of magnitude. Since they don't normally have thrusters to deorbit a drag shute like this is a cheap easy way for responsible operators to keep space tidy.

This is all assuming the satellite survives it's mission to the point where de-orbiting is desired/option. Many satellites lose control to general wear and tear, radiation damage or debris strikes such as Envisat.

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PrematureJack t1_jd1vf75 wrote

Not all satellites. Most of the satellites I’ve worked on simply turn their solar arrays into a high drag configuration if they need to make adjustments to miss something, and when they reach end of life they just turn and stay that way to deorbit. If you’re in Low earth orbit even a dead sat will deorbit in about 5-10 years.

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tx69er t1_jd0l4qz wrote

Some do, but typically not these little microsattelites. Little ones like this typically rely solely on drag, which can take a while.

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LooieA t1_jd2bv0h wrote

Scientific definition of “a while”?

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tx69er t1_jd6v023 wrote

Tens of years or so, as opposed to a few hours to a few days with a thruster.

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PineappleLemur t1_jd10iuk wrote

There's a lot of space junk just floating around.. dead satellite and such that are just waiting to collide with something.

Fairing pieces with no control for example.

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Baremegigjen t1_jd2zsjp wrote

Most operational satellites do for station keeping in order to maintain the proper orbit and to move them out of the orbit after their useful life so other satellites can take their place. Depending on the orbit some are deorbited and come back to earth; otters are boosted up into orbits that aren’t used.

The issue is everything in orbit is technically a satellite and there’s are tons of junk up there from rocket bodies and formerly operational satellites to debris of all types including from Russia blowing up one of their satellites a year or two ago, leaving hundreds of pieces of various sizes orbiting the earth. All of which need to be tracked to so as to avoid collisions with objects currently in space (ISS and other satellites) or to be launched (you don’t want to lose a $1B satellite by launching into a debris cloud.

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NinjaMoreLikeANonja t1_jd582os wrote

Changing trajectory means changing orbit and changing orbit takes energy. The presumed (and soon to be legally mandated) end of life goal of all smallsats and cubesats is to burn up in the atmosphere. You can do that by reserving a last gasp of propellant on the satellite to lower the satellite's orbit, but that assumes that there is a thruster on board somewhere. A lot of small satellites don't have thrusters. The drag sail approach is nice because it's passive, and all the energy required is collected from atmospheric impact rather than stored on the satellite as a propellant of some kind.

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_shapeshifting t1_jd0pe06 wrote

but what if the one thing you send up there is responsible for eliminating 100x it's mass in disparate debris?

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threebillion6 t1_jd0uh5y wrote

How? Are you picking up that stuff and carrying it around while you collect the rest of the stuff? Added mass means more fuel you need to take up, to be able to move between orbits. Sending up the ability to deorbit itself removes the need for us to send up another thing. Along with actually getting that thing into orbit. Who's gonna pay for it? These are just honest questions. I'd love to be able to send up something that can maneuver around and collect debris, but it's an engineering feat to do that.

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_shapeshifting t1_jd0zcqw wrote

you don't actually collect it, you use a laser to turn small deadly things into significantly less dense, less deadly clouds of plasma.

EDIT: the same people who launch their own commercial satellites have a financial incentive to pay for the solution to make their satellites safer.

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threebillion6 t1_jd10mt3 wrote

How powerful a laser are we talking about? I could see that going badly very quickly.

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_shapeshifting t1_jd12pst wrote

powerful enough.

I can imagine paint flecks destroying the ISS, so which one do you want: a solution with risks or risks without solution?

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KruppeTheWise t1_jd10nud wrote

If you aim the laser correctly the gases boiling off the sats surface will push it out of orbit too.

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_shapeshifting t1_jd1344t wrote

that'd be a really strong laser lol.

I'm imagining this as a solution for the 1 million+ objects the size of flecks of paint. maybe the ones as big as a marble.

to boil a whole satellite would be hardcore but also insane

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n1elkyfan t1_jd19xy4 wrote

One idea is to use something like rocket labs which is the Photon. It's used as a kickstage for other satellites but could be used to deorbit other space junk since it is usually deorbited anyways.

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