Monthly Archives: April 2014

The Future of Satellite Maintenance?

Mini robots

Prepare to be blown away.  The absolute coolness of the video below, if we were using Top Gear’s “Cool Wall,” would put it beyond “Sub-Zero” to “Absolute Zero.”

The video doesn’t really say anything about satellites, so you might be wondering, “Why is this video on this blog?”  Here’s my answer:  what you’re seeing is possibly the future for satellite repair and maintenance.  These miniature robots are very specialized, very small, probably relatively cheap, and very light.  Such characteristics would make them appropriate companions to satellites.

They could “live” in a compartment, or some other protected area, and come out only to conduct maintenance or other activities.  These tiny robots might be a better option than sending out a repair satellite.  And because they’re using magnets to move around, there’s probably very little chance of them flinging off of a satellite.  Indeed, they might still be able to conduct critical functions during emergency maneuvers.  In essence, “self-repairing” satellites might become possible.

For long-term future guesses about this technology, orbital manufacturing facilities above the Earth might become a reality.  These robots (and the surfaces required) could easily be transported into space.  Barring a “Skynet” event, or just a general robot uprising demanding wage parity, the little robots would be working in a naturally sterile environment, which is ideal for some manufacturing.

Of course, this is just throwing the idea-noodles at the wall.  But it’s fun to do that–and these little robots are just quite cool!


SpaceX News: An F9R video and Letters from Senator McCain


Here are two  little “love letters” from Senator McCain.  One is to the Secretary of the Air Force, the other to the Department of Defense Inspector General (DoD IG).  The gist of both is that he takes issue with the United States Air Force’s arguments for cutting down the number of available launches in the EELV contract (which might raise ULA launch prices more), asking how such an action is an aggressive pursuit of competition.  The senator wants to save taxpayers money, and it sounds like he believes open competition on the EELV contract would be a way to do so.

He cites three of the USAF’s arguments about why seven launches were removed from competition, saying a few of them are “specious:”  1) Decreased DoD demand for satellite replacements, 2) payload weight-growth, and 3) making sure the ULA gets its contractual due.

Senator McCain is asking the DoD IG to investigate the USAF’s claims, specifically to investigate their claims with the understanding that new developments, such as SpaceX’s seemingly reliable but short Falcon 9 launch record, might help keep taxpayer costs down for launch.  I’m hopeful other senators have sent similar probing questions–but maybe they’re letting McCain spearhead this.  It will be interesting to see how the USAF  Secretary responds, as well as the DoD IG.  Right now, the USAF justification is that DoD satellites are too precious and costly (which is another big DoD spending problem) to entrust with a new company like SpaceX.

Then perhaps the question that needs to be asked is:  what would it take for the DoD to accept not just SpaceX’s launch system, but any new launch system, as a viable competitive launch platform for their satellites?  I don’t know if acceptability requirements have even been established yet, and if they haven’t, then the USAF hasn’t complied with the direction given to them to “aggressively introduce a competitive procurement environment….”  It would behoove them to get all players, current and potential, together to figure that part out.  Maybe this is why Elon Musk has been badgering both the ULA and the USAF:  he wants to know what it would take to be involved, and no one is giving the answer.

In the meantime, SpaceX keeps moving ahead, not waiting.  Last week, SpaceX tested the vertical launch and safe landing of a Falcon 9 Reusable.  The F9R is using the latest stage one rocket body SpaceX has already used for a few launches now (the latest one on 18 April).  The video below represents SpaceX’s vision for all its rockets:  return safely to be reused the same or next day.  Less time equals less customer money spent on launching these potential reusable rockets.

Why space matters: HEO Satellite Operations, Part 1–You’ve Never Kepled?

In previous lessons you’ve learned about the Low Earth Orbit (LEO) and the Geosynchronous Orbit (GEO).  There are pros and cons in using each orbit.  Generally for satellites in LEO orbit, particularly imagery satellites like those owned by DigitalGlobe and SkyBox, the closer the satellites are to the Earth, the more detail of the objects and activities on the Earth’s surface they’re able to see.

But the con for LEO imagery satellites is that they’re so close, their Field of Regard (FOR) and Field of View (FOV) are very limited (go here for a reminder of what FOV and FOR are).  This means they can see pretty much what is right under them and a little bit around them—but,  and some of this depends on the camera and lens technology, it will be fairly detailed.

The GEO satellites FOR allow for them to see the whole of the Earth’s surface that’s facing them (the Earth’s disk).  And they stay over that particular portion of the Earth because their orbital speed matches the speed of the Earth’s rotation.  But, while weather imagery satellites can give a good understanding of patterns, they can’t see the details.  They’re just too far out.

Perhaps there’s another orbit, one that possibly bridges the capabilities between the other two orbits?  Such an orbit exists, but it’s very eccentric.  It’s an orbit that can be up close to the Earth, but also far away.  It’s called a Highly Elliptical Orbit (HEO).  It’s a very interesting orbit in which many different missions are accomplished.  Also, notice the trend:  LEO, GEO, and HEO.  Space operators try to keep things simple and rhyming acronyms are one way to do it.  Plus we’re not that smart, so if we can memorize this stuff, you can.

The HEO name is a fairly good description of the orbit, but for those who require a visual aid, imagine an orbit that’s shaped like an American football, with the tips more rounded.  This is an ellipse.


Now imagine that football is tilted in in a kicking tee. This represents the orbit’s inclination.  It’s at a particular angle with the Earth’s equator.  And yes, LEO satellites also have inclination.

Football 2

But this demonstrates a HEO property that’s different from a LEO.  Like LEO, a HEO orbits around two fixed points, called foci.  You may be wondering how a LEO has two fixed points—a LEO is typically circular.  And that’s still true, but with two points.  In the case of the LEO circular path, the two fixed points are much closer together.  They are nearly on top of each other.

An elliptical orbit, on the other hand, has two fixed points, but they are much further away from each other.  In our example, the football’s shape wraps around the Earth, with one end of the football (and therefore, one end of the orbital ellipse) closer to the Earth than the other.  The Earth occupies one of the two fixed points within the HEO.  The other fixed point is not occupied by anything.

Football 3

That shape, tilt, and closeness of one end to the Earth is, in essence, the path of a satellite’s Highly Elliptical Orbit.   And now, without the football:

Football 4

The part of the elliptical orbital path that’s closest to the Earth is called perigee.  The part of the orbital path that’s farthest away from the Earth is called apogee.  So congratulations!!  You’ve just learned one of Kepler’s Laws of Planetary motion:  “The orbit of a planet is an ellipse with the Sun at one of the two foci.”  –, Kepler’s laws of planetary motion.  If the name “Kepler” sounds familiar, it’s also because a satellite was named after him.  You can go the NASA satellite mission website to understand why it’s named Kepler, and what it’s doing.

I wonder what else there is to learn next lesson about HEO?


Astronaut Pay

Astronaut Pay

Sure, some of us say we’d work in space for free.  We’re pretty nerdy that way.  I’m pretty sure, then, for these astronauts, that getting paid to do something they love, is icing on the cake.  I’m assuming astronauts love their job.  There’s a lot of work and commitment involved to become an astronaut, though, so they should get some sort of pay.

How much does an astronaut make?  This Universe Today post lists the different space agencies, and the range of pay each country agency pays its astronauts.  The pay scales don’t look bad, but as with most jobs, it looks like being a more senior astronaut with more experience has its perks.   The ranges offered by each agency looks pretty comparable, although the Canadians, known globally for being terrible tippers, are the most generous.

The post gives some tips to those interested in earning that Astronaut’s Pay.  You have the opportunity earn the pay and the name if you have the “Right Stuff,” that is.  It’s not too long of a post, so give it a read if you’re curious about the amount of money governments pay the people who are taking risks in space.

DIY Space: The Zero Gravity Cocktail Project (and A Project You Can Do)

Image from Make Magazine. Go there to learn more about Zero Gravity Cocktails.

Somehow, for some reason, cocktails and space seemed to be linked.  It was only natural, then, for someone to design a cocktail glass for space.  This is trickier than it sounds, and Make Magazine’s post goes into some detail of the re-invention of the cocktail glass.

Think about the main ingredient required for enjoying a cocktail here on Earth:  gravity.  It’s very easy for us to: 1) fill the glass (need gravity for that), 2) tilt glass towards mouth, and 3) liquid pours from glass into mouth (again, gravity).

Now, think of what will happen when you try to pour in a micro-gravity environment.  That’s right–nothing.  The liquid will remain in a bottle or pitcher and not pour into the glass.  But let’s assume you’ve managed to somehow get the liquid from bottle to glass.  Now try to get it from glass into you.  And again, in micro-gravity, the liquid will remain in the glass, and you are just a frustrated wanna-be lush.

And so, there are a few people determined to make sure the Nick and Nora wanna-bes in space will not be without their cocktail.  Ergo, the dawning of new micro-gravity drinkware.  Read Make’s post for more detail.  But if you want to see how some engineers have designed a drinking “cup” for micro-gravity environments, watch the video below (and thanks to Michael Spencer for bringing this to my attention).

Sure, it’s for coffee.  And yes, it looks silly.  But coffee is important, too.  You can go to these directions here, if you want to make “space coffee.”

So that’s kind of interesting, but where’s the DIY?  Right here, of course.  Make also has instructions for how to build a model rocket launching system, called Launchit.  It looks pretty nice and has big red switches and buttons.  Great for budding missileers.