Rocket Science for the Rest of Us

We had to put our beloved dog to sleep today.  Please excuse me for not blogging.  I'll be back soon.

Sounds like a literary SF novel, doesn't it?  In fact, it's an actual blog by space station astronaut Don Pettit, who returned to earth this month.  It's life on the space station as told by a zuccini plant that is growing on the station as an experiment on aeroponics to see how microgravity affects plant growth.

Zuc blogs about what's going on in his life and the life of the astronauts who are studying him.  Sometimes, things are a little silly

Great news; I have a baby brother sprout! Gardener just showed me baby Zuc. He is strong and healthy and ready to move from the sprouter into his own aeroponic bag. While Broccoli and Sunflower are great companions, there is nothing quite like having a zucchini to zucchini conversation.

 Other times, however, zuc talks about the experiments going on in the station, both on himself and in other fields.

Sunflower has brown patch.  His leaves are covered with dry, dark blotches.  He is not happy.  Gardener says it looks like a fungus.  I am afraid that if something is not done we are going to lose Sunflower.  The crew medical kit is designed for animals not plants so there are no medications for this disease.  Gardener is treating Sunflower with a disinfectant wipe that has an antibacterial agent called BZK (Benzalkonium chloride).  We do not know if this is going to work.  Our spacecraft is designed for animals so life can be a struggle for plants.  On the frontier, the answers are not found in the back of the book and sometimes you have to venture into the unknown and improvise.

 Sometimes, Zuc talks about current events.  he's a bit of a Renaissance plant, as you'll see:

We released Dragon today. The treasures he brought were traded for some of our goods and then he went on his way. I like this concept; Dragon brings us things we can use in exchange for things we have made on orbit. The things we make on orbit are samples from our scientific experiments. They have great value to the Big Gardener on Earth. Explorers use to bring back silk and spices. Now we bring back scientific samples, crystals, blood, and urine. Within these goods lay spoils more valuable that plundered gold for they are the key to advancing our knowledge. Sometimes we give Dragon broken spacecraft parts that he will repair and bring back on his next visit. Before we closed the hatch, we placed a picture of our crew on the bulkhead. Dragon seemed anxious to go. I guess when a Dragon visits, they do not stay long.

Sometimes, the astronauts add to the blog as well, so you get human and plant perspective.  It's a fun way to keep up on activities in the ISS.  I recommend it for some light but interesting reading.

I happened across this doing research for another blog, and I'm glad I did.

Photo courtesy of NASA website.

I was just a kid when Pioneer 10 and 11 were launched to explore our solar system.  Now, I have children older than I was back in '73, and these probes have flown the asteroid belt, checked out Jupiter and Saturn, and are on their way out of the solar system.  However, they've been slowing down, and that's a mystery that has taken nearly a decade to solve.

NASA scientists first noticed the slowdown in the 80s, but passed it off as "a transient phenomenon resulting from dribbles of propellant left in the probe's lines, according to researchers." (Space News, July 23, 2012).  However, the craft kept on slowing, albeit slightly, and in 1998, they no longer expected the problem to stop.  Certainly, they couldn't do anything about it, but it did leave a question:  What was slowing them down?

They dubbed it the "Pioneer Anomaly" and went to far as to suggest that they were dealing with a new type of physics that contradicted Einstein's General Theory of Relativity.  how exciting would that be?

In 2004, Slava Turyshev of Jet Propulsion Laboratory decided to study the phenomenon.  He and his colleagues searched through the Pioneer probes' telemetry--43 gigabytes of information, much of it on on magnetic tapes that had to be converted as well as digitized files.  Eight years later, they published their discovery in Physical Review Letters.

It was heat.

Yep, that little bit of heat caused by electricity running through the systems of the Pioneer probes actually pushed back on the probes, causing them to slow.  Space News quotes Turyshev with saying it was like the photons of your car's headlights pushing back on your car. Apparently, however, when dealing with the speeds of the spacecraft and the distances and environment of space, that can have a noticeable, albeit very subtle, effect.

How mundane is this--and yet so awesome!  First, there's the simple idea that something so basic can have such a profound effect that we might even doubt General Relativity.  How much we don't know about the practicalities of space travel!

Secondly, think about all the work, all the minutia, data crunching, file conversion, etc. that went into figuring out something that in hindsight seems so ordinary.  Eight years!  I don't know about you, but I can get tired and bored just trying to find a coding problem on my website, and these guys went through 53 years' worth of data between the two probes.

My hat's off to you, Dr. Turyshev, and to all who worked so diligently on this mystery.  Next time I turn on my headlights, I'll think of you.

For more reading:

About the discovery:  http://www.jpl.nasa.gov/news/news.cfm?release=2012-209
About Pioneer 10 and 11:  http://www.nasa.gov/centers/ames/missions/archive/pioneer10-11.html

**BTW, my apologies for not posting last Tuesday's space studies.  I'll discuss Doppler effects with the next lesson on Tuesday.

I don't know about you, but sometimes, I wonder why, when we've already proven we an get people to the moon and regularly into space, it seems to hard to do it again.  After all--why should adapting the ideas of the past to the technologies of the present be so difficult and take so much time?

I'm actually going to be asking this of several new space agencies, but for now, I leave you with this video of an up-and-coming company in the commercial space industry--Liberty Launch.  Liberty is using current rocket technologies, adapting them to the greater mission of taking men into space.  What I hope you'll get out of this video is how even adding a quarter of an inch thickness to a panel means careful testing.  After all, if a weld fails, people die.

Ariane 5 is, as a part of Ariane rocket family, an expendable launch system used to deliver payloads into geostationary transfer orbit (GTO) or low Earth orbit (LEO). Ariane 5 rockets are manufactured under the authority of the European Space Agency (ESA) and the Centre National d'Etudes Spatiales (CNES). Astrium, an EADS company, is the prime contractor for the vehicles, leading a consortium of sub-contractors. Ariane 5 is operated and marketed by Arianespace as part of the Ariane programme.

The lesson is here: http://www2.jpl.nasa.gov/basics/bsf6-3.php

Another straightforward lesson about the spectrum, how it's categorized and why its useful to study it.  In short, certain elements can absorb specific frequencies, so by getting a spectral reading, we can determine the composition of the planet.  It's also an important science for asteroid mining.  (This is an old article, but explains why.  This month's Popular Mechanics has a terrific article on asteroid mining.  I'll review it later.)

Link to Lesson:  http://www2.jpl.nasa.gov/basics/bsf6-2.php

Once again, we're getting some basic concepts that are used in engineering and astrophysics.  It's been interesting, though, because I learned a couple of things.  I'd heard that light is the only thing that is described both as a wave and a particle.  When I'd not realized is that anything on the electromagnetic spectrum (like radio signals) can be described the same ways.  It's just that the particle idea is better used when you start getting into the spectrum of light.

I didn't really know what decibels were, so this lesson was good for that.  However, it's been a long time since I've worked with logarithms, so I did some looking on YouTube.  Here are two to share with you. 

Decibels explained on an engineering level: This one is good for showing why decibels are useful as well as what they are.

Decibels explained on a more elementary level:  This one gives a little history.

Found a couple more videos of Uncle John, lest you think he's all jokes and funny stories:

From one of his missions:

2007, talking about the challenges of the Mars mission and spaceflight.

Lesson: http://www2.jpl.nasa.gov/basics/bsf6-1.php

Just one thought on this one--relief.  For some reason, I had it in my head that all the music, TV, YouTube vids, etc that we've been broadcasting were going to be heard by some alien race, but thanks to the inverse-square law, they are probably too faint to hear outside the "local" area.

Of course, that removed the argument that there is life out there, they have seen Jersey Shore*, and they have no intention of contacting us. Ever.


* My daughter picked this show.  I had Gilligan's Island, but that's too old.  My next thought was Parks and Rec, although I'm sure there are many worse than either of these.  Like I said, relief.