Satellite Diaries

If you use off-the-shelf electronics parts instead of expensive, hard-to-find space-rated gear, will your satellite work?  The process of 'derating' will let you do this.  Engineer Amanda Shields contributes today's guest column.I'm becoming very familiar with derating and the joys of it.   Electrical components for spacecraft have to be derated. Basically, that means that you take the electrical component and you look at the data sheet for that piece and you have to say "Well, according to the datasheet it can have a maximum input power of XX, but NASA says that it has to be derated to 80% of that, so we can actually only have an input power of YY".

A Mojave rocket company, an asteroid hunter, and a web pundit walk into a conference.  The badge person says, "what is this some kind of joke?"Okay, we gotta get to space somehow.  Here's what's new in the private space race industry.  What ties these 4 newsbits together is it's all about having fun.SatMagazine (March 2012) reports

Today's primer: orbital mechanics, or how we have to manuever to catch debris.  There's a lot of debris in low earth orbit, ranging from paint chips and spare bolts to a heavy toolbox up through entirely dead satellites.  It's tracked, it's plentiful, it was even featured in Wall-E.  How is it a satellite in orbit runs into debris?

Rockets are powerful stuff, and satellites and astronauts experience tremendous G-forces pushing down on them during launch.  For picosatellite work, it is necessary that your design be able to withstand forces equivalent to perhaps 10 times Earth gravity-- 10Gs.  To test this, the easiest way is to build a centrifuge.Think of the spinning bucket gimmick.  If you tie a bucket to a rope and fill it with water, you can make the bucket swing in a loop-the-loop over your head and not spill, as long as it is spinning fast enough.  You need enough spin to counteract the 1G of the Earth's pull, so you need a spinning centrifuge of at least >1G.

I've some background in space weather-- the influence of solar activity on Earth and near-Earth orbits.  My new job as a professor at Capitol College has brought me into contact with several bright students working on using picosatellites to test our orbital debris removal concepts.  Further, the number of other groups doing balloon and picosatellite work is increasing (yay!)  So it's time to update this column more frequently with not only my progress, but stories of other pico teams.

Calliope integration and testing is on hold until Spring break, possibly until Summer.  This is driven by two factors: my new job has me short on time, and InterOrbital's deadlines have removed a strong time pressure.  It's a good situation-- it's always better to have more time.One aspect of my new job is presenting mission scenarios and case studies from Mission Operations.  I posted a key trade in my science blog, looking at explosive bolts versus springs from a risk point of view.  In retrospect, this column-- being about crunchy engineering topics-- may have been a better venue.

While I've been strangely silent, the space industry is surging ahead.  I have, off the record, been told of small companies looking to invest $10s of millions into launchers, of new picosatellite designs (like Cubesat and Tubesat) being bandied about, of a possible new East Coast space port.  NASA is publically funding multiple potential launch providers.

Dan Reus of the creative instigator/outfit Openly Disruptive ("the future will be what we make it") tossed me this note: I thought you might like to see the mention of you and Project Calliope in a recent post by our local alternative news weekly: http://blogs.riverfronttimes.com/rftmusic/2011/08/dan_reus_outerspace_m… 

Why would anyone build a Tubesat when the Cubesat open standard tends to dominate the picosatellite world?  Well, first, there's only been a bit over a dozen Cubesats, so it's a wide open field.  Second, the Tubesat design is actually a kit, including schematics that are pre-integrated, rather than being an open spec like Cubesat. In some ways, it's a little odd to compare them, much like you can't really compare an iPhone to an Android smartphone.  iPhones are a device; Android is an operating system used in over 75 different devices.  Similarly, Tubesat is a device; Cubesat is a specification that people fit their own ideas into.  Different approaches.

A fun update, Interorbital lists their filled manifest for their first N30 launch.  This is everyone who is building a Tubesat or Cubesat for their first private launch.  Put another way, these are all of Calliope's kinfolk.  Pioneers, every one of them.

MSNBC reported on the latest set of new NASA prizes:NASA today announced three new competitions offering a total of $5
million in prizes — and only one of them involves actually putting
something in outer space.I'm a huge fan of prizes.  Although I love NASA's work, I dream of a day where fully half of NASA's workload consists of evaluating prize entries by indy companies that are hitting specific get-us-to-space benchmarks.

What do you get when you mix Mad Men styling, IKEA how-to, and NASA high tech?  In an incredibly terse 1 minute and 28 seconds, with no sound needed, NASA asks "So, You Want to Build a Satellite?" and explains why rocket science is hard.  Seriously, this is the sort of video that you don't need sound, and it features no talking heads or chatty scientists.  It's an elegant, straightforward wake-up call about the intrinsic difficulties that space exploration brings.