November 20, 2013

Let's go to Europa

Neil deGrasse Tyson, astrophysicist, has said that he wants to go ice fishing on Europa.  I do, too.  I started thinking about this again recently after watching a stupid movie.  I thought it was going to be a good space flick, and it ended up being a lame found-footage movie.  The surprising thing about this movie was that it got a lot of the science right.  There was even a clip of Neil deGrasse Tyson and his ice fishing comment.  Europa is one of the moons of the planet Jupiter.  It's slightly smaller than Earth's Moon, but it's big enough so that when looking at Jupiter through my small telescope, I can see it along with Jupiter's three other large moons.  Pretty cool.

Europa (top right) with her sister Galilean moons; image courtesy NASA/JPL

I am an insane astronomy junkie and got completely sidetracked while looking for NASA images of Europa.  I could look at NASA photos for hours.  I'm mesmerized by the planets and their moons.  Anyway, the above is a composite photo showing Jupiter's four largest moons, called the Galilean moons because they were discovered by Galileo.  Clockwise from the top left, they are Io, Europa, Callisto, and Ganymede.  They're beautiful.

So, Europa.  Why is Europa so interesting?  Europa is one of the two top candidates for finding life outside of Earth in our solar system.  (Enceladus, moon of Saturn, is the other.)  Europa is covered in ice.  The same extreme tidal forces from Jupiter that make Io the most volcanically active piece of real estate in the solar system generate enough heat in Europa to melt the ice and create an ocean of water under the surface.  Every place on Earth in which people have found water, no matter how hostile the environment, people have found life.  The ice on the surface of Europa is several miles thick, which should be thick enough to shield living things from the massive amount of radiation emitted by Jupiter.  Microbial life.  Possibly multicellular life.  In my wildest dreams, the Europan equivalent of fish.  I'm not talking about intelligent life that could communicate with us.

Europa's cracked ice surface; image courtesy NASA/JPL

The premise of this bad movie I saw was that astronauts were sent from Earth to land on Europa and seek out life.  I wish!  We don't have the technology right now to do that, and NASA has become so risk-adverse that they wouldn't even if we did.  We could send a robotic lander, though.  Several missions like this have been proposed only to be shot down in favor of yet more Mars missions.  Once MAVEN reaches Mars, NASA will have two rovers on the surface and three satellites in orbit.  NASA has become fixated on Mars to the detriment of the rest of the solar system.  There is not one mission in preparation with funding that would visit the outer planets.  New Horizons is on its way to Pluto, and Juno is on its way to Jupiter, but nothing is in the pipeline to follow them.  I was disappointed that in the latest round of approvals, a mission to Uranus was shelved.  It takes a long time to plan and execute these missions because of the vast amount of time it takes to travel so far away.  They need to get on this before I die!  I'm serious.  If they approved a mission to Neptune or Uranus this year, it probably wouldn't get there until I was retirement age.  I'm already never going to see people walk on Mars or even the Moon.  I'd like to see more photos of Neptune and Uranus and find out more about these mysterious ice giants.  The only mission to visit them was Voyager 2 in the 80s.  We have a couple of photos and a little bit of data from flybys of each planet.  That's it.  So many questions!  No answers.  No way to get answers without going there.  

I digress.  Europa.  I firmly believe there is some kind of life there.  Those ruddy stains on the surface- scientists believe that they come from the subsurface ocean bursting out through the cracks in the ice.  What is making it that color??  As Carl Sagan said, "Extraordinary claims require extraordinary evidence."  A mission to Europa could find it.  I came across something interesting- Objective Europa.  It looks like this group wants to make the bad movie come true, as a one-way trip.  Go for it, Objective Europa!  There's no way people could survive the intense radiation that deep in the Jovian magnetosphere, but since they aren't planning on coming back, I suppose that's not an issue.  Not that I think Objective Europa will happen, but we need something to inspire people.  The current generation of astronauts and engineers saw Neil Armstrong and Buzz Aldrin walk on the Moon.  That was supposed to be our first step out into space.  We need to get out there if our species is to survive.  Low Earth orbit isn't good enough.  There's a reason the Drake Equation has a spot for how long civilizations last.  Odds are, they don't.  Ah, nothing like pessimism to end a blog post.  So, here is a random astronomy factoid that rattles around my brain.

The Moon is far away.  

Yeah, Jen, of course the Moon is far away, you say.  No, but it really is far.  Let's say that a basketball is the Earth and a tennis ball is the Moon.  That's to scale.  How far away would they have to be to accurately represent the distance between the Moon and the Earth?  Stop and think about your answer before you read on.  Most people would probably hold them one to two feet apart.  Not even close.  Think of your average classroom.  I'll hold the basketball and stand at the front.  You take the tennis ball and walk to the back.  That's about right- almost twenty-five feet away.  See, the Moon is far away.  So the next time the media is freaking out because an asteroid is passing between the Earth and the Moon, don't worry.  The Moon is 238,900 miles away.  That's a lot of space.  

I love photos like this.  Image courtesy NASA/JPL

No comments:

Post a Comment

Related Posts Plugin for WordPress, Blogger...