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Hundreds of cute tiny satellites are doomed to burn up in the Earth's atmosphere next week

A plan to send dozens upon dozens of circuit board-sized satellites up into space at the same time in a swarm has come unstuck.

The tiny Sprite satellites being dispersed from the spinning KickSat. Image: KickSat
The tiny Sprite satellites being dispersed from the spinning KickSat. Image: KickSat

The first ever artifical satellite of Earth, Sputnik, was in orbit for only three months before burning up in the Earth's atmosphere. It was not a particularly advanced satellite, all told - it beeped out a regular signal every 0.3 seconds, containing measurements of its internal temperature and pressure readings. Still, Soviet scientists were able to derive useful measurements of the Earth's upper atmosphere by noticing subtle changes in those regular beeps. Beep... beep... beep... until it burned up as it fell back down to Earth, where the Space Race was now enthusiastically underway.

Technology in 2014 allows us to replicate Sputnik's beeps and measurements for less money, and at a much smaller scale. This was partly the inspiration for KickSat, a successful Kickstarter that reached its funding goal in 2011. Instead of launching one massive satellite with multiple functions, costing millions of dollars, the concept was to instead send up one cheap, off-the-shelf CubeSat, which would then deploy hundreds of further tiny circuit board-sized called Sprites into a swarm in the same orbit.

The Sprites are seriously tiny - they're only 2cm on each side, which is slightly larger than a stamp:

Image: KickSat

The Sprites were developed by Cornell's Space Systems Design Studio, and, like Sputnik, they include a one-way radio that will broadcast basic information back to whoever is listening. The 315 backers of the KickStarter - be they schools, university groups, space enthusiasts, or merely the curious - each got their own Sprite on KickSat, and were able to each decide what kind of message they wanted them to send back to Earth. The larger, more scientifically-useful project (from the perspective of the Cornell team) would have been that the Sprites would allow the study of the behaviour of tiny dust particles on the edge of space. 

Here's a video showing what KickSat should look like as the Sprites deploy:

Here's Cornell Space Systems Design Studio team member Zachary Manchester:

Inspired by the success of the first Sputnik launch in 1957, we focus on a simple, feasible, but genuinely new design. For three weeks, the 23 inch diameter sphere of Sputnik I broadcast its internal temperature and pressure as it orbited and hinted at the potential of artificial satellites. A half century later, we expect to duplicate Sputnik’s achievement using less than one ten-millionth of its mass. Our design packages the traditional spacecraft systems (power, propulsion, communications, etc) onto a single silicon microchip smaller than a dime and unconstrained by onboard fuel.

However, it appears that there won't be a happy ending for these tiny Sprites. Something's gone wrong. KickSat rode into orbit as part of the payload on SpaceX's latest International Space Station resupply mission, which launched on 18 April. KickSat was only supposed to, like Sputnik, remain in a relatively low orbit - far below that of the ISS - as its mission was only intended to take a few weeks at most before everything burned up in the atmosphere.

KickSat's internal clock has reset itself, with radiation being the most likely culprit. It was meant to deploy its payload of Sprites on 4 May, but since that date has now been pushed back to 16 May - by which time the KickSat team think that it'll be too late, and the satellite will have already re-entered Earth's atmosphere. Manchester has written a blog explaining the situation:

We've spent the last couple of days here at Cornell trying to think of every possible contingency, but it seems there aren't very many options right now. KickSat's uplink radio, which we could use to command the deployment, can't turn on unless the batteries reach 8 volts, and it doesn't look like they'll reach that level in time.

While the situation looks a little bleak, there is still some hope that the batteries may recharge sufficiently to command the satellite. There is also a small chance that KickSat could remain in orbit until the 16th, at which point the timer would set off the deployment as originally planned. We'll continue tracking KickSat over the next few days with the help of the ham community, so that we can keep track of its battery voltage and the Sprite deployment status.

Those poor little Sprites, doomed to die before they've even lived.