Finals are, in fact, over, so I can re-prioritize this. The first thing I did in catching up on the astronomy news I missed in the last week or two was checking up on the Mars rover.
I didn't want to sound like a spoiled child. But come on, there's been no real data released since that measly little announcement at the conference at the beginning of December! Curiosity's been "investigating" rocks, taking photos, sniffing the air, and digging around for over five months. It would be really nice to have heard more than "we didn't expect the wind to blow in this direction" and "oh look, more chlorates."
Short post tonight, just venting the frustration. I know they have to sift their own data for some time, but after this long I would've expected we'd at least have whatever new info they've gleaned from the first on-the-ground photos.
Showing posts with label Curiosity rover. Show all posts
Showing posts with label Curiosity rover. Show all posts
Wednesday, December 19, 2012
Wednesday, November 28, 2012
Can You See Me Now?
I've mentioned this before, but one of the things that I find the most amazing about space is the vastness. To quote the Hitchhiker's Guide to the Galaxy (I often do), "Space is big. Really big. You just won't believe how vastly, hugely, mind-bogglingly
big it is." It's very true. The more you think about the distances and time frames involved in properly studying the Universe, the more immense and incalculable it seems.
This bothers a lot of people, in much the same way as looking down from a height does. I'm going to take advantage of this opportunity to evoke the sensation in you, readers. Thinking that it takes 25,000 miles to go once around our planet's equator seems like a fairly large distance, right? It's a little over twice as far as the average person commutes to work in a year (my own calculations, based on Census data -- see bottom of page for how I got it). Then you think that you'd have to drive 9.5 times the Earth's circumference to get to our nearest neighbor, the Moon. To drive to Mars at the same speed, you would have to cover 3000 times the distance of your annual commute, or 1440 Earth circumferences. All that, and we haven't even left the inner solar system yet, much less looked at other stars.
It just gets more staggering from there; beyond our solar system are widely-spaced stars, beyond our local stars are the far-flung arms of our galaxy, beyond our galaxy are distant other galaxies in the Local Group, beyond the Local Group are other chains of galaxies spreading out into the Universe, at distances where even the light of billions of suns are a faint smudge in our telescopes. Just outside the (suddenly tiny) confines of our atmosphere is a vast, black stretch of...almost nothing...for distances that still take our most modern propulsion systems months to travel to.
And that's just space; don't look at time scales unless you want to feel real cosmic vertigo.
I find this all oddly comforting. There's something intensely personal about the fact that, in all this vastness, there is one tiny rock around one totally average star that is just right for our form of life to develop. Then there's all the other rocks out there that could support the same type of life. And all the ones that could have other kinds of life that we wouldn't even recognize. It doesn't matter how you think this Universe started, scientific or otherwise -- anyone who can think about these things and not get totally awestruck is missing out on one of the biggest beauties we know.
So I want to share some of the things that help make the Universe a warmer, fuzzier place to think about again:
*Fun Census calculations: I used the 2011 ACS numbers for average commute time for the entire US. (while I have your ear, the American Community Survey recently had its funding axed in Congress; this seriously erodes the information we have about the state of our nation's populace. Go read about about the fight, it was all over major media sources.) This number was 25.3 minutes. I assumed 55 mph as a median driving speed, to factor in both highways and local traffic. This gives 23 miles commute, one-way. Double that for a day's trip, 46 miles. Now, multiply that by the traditional 5 day workweek and 50 weeks of work per year, and you get approximately 11,600 miles per year.
This bothers a lot of people, in much the same way as looking down from a height does. I'm going to take advantage of this opportunity to evoke the sensation in you, readers. Thinking that it takes 25,000 miles to go once around our planet's equator seems like a fairly large distance, right? It's a little over twice as far as the average person commutes to work in a year (my own calculations, based on Census data -- see bottom of page for how I got it). Then you think that you'd have to drive 9.5 times the Earth's circumference to get to our nearest neighbor, the Moon. To drive to Mars at the same speed, you would have to cover 3000 times the distance of your annual commute, or 1440 Earth circumferences. All that, and we haven't even left the inner solar system yet, much less looked at other stars.
It just gets more staggering from there; beyond our solar system are widely-spaced stars, beyond our local stars are the far-flung arms of our galaxy, beyond our galaxy are distant other galaxies in the Local Group, beyond the Local Group are other chains of galaxies spreading out into the Universe, at distances where even the light of billions of suns are a faint smudge in our telescopes. Just outside the (suddenly tiny) confines of our atmosphere is a vast, black stretch of...almost nothing...for distances that still take our most modern propulsion systems months to travel to.
And that's just space; don't look at time scales unless you want to feel real cosmic vertigo.
I find this all oddly comforting. There's something intensely personal about the fact that, in all this vastness, there is one tiny rock around one totally average star that is just right for our form of life to develop. Then there's all the other rocks out there that could support the same type of life. And all the ones that could have other kinds of life that we wouldn't even recognize. It doesn't matter how you think this Universe started, scientific or otherwise -- anyone who can think about these things and not get totally awestruck is missing out on one of the biggest beauties we know.
So I want to share some of the things that help make the Universe a warmer, fuzzier place to think about again:
- SETI (http://www.seti.org/): de-funded by the government after less than a year's actual operation, the Search for ExtraTerrestrial Intelligence has not been idle. Looking for signals from other planets, the now-private group uses its own radio telescopes (or gets time on other telescopes pointing in likely directions) and gathers data. The head scientist, Seth Shostak, recently claimed that SETI was likely to find an alien signal within the next 25 years . You can even help them sort through it by running a SETI@home program while your computer is idling.
- The Drake Equation: this equation applies to our galaxy, or any other galaxy with at least one civilization. It basically summarizes all of intelligent-life astrobiology. Made up of about 7 terms (depending upon which version you use), it tells you just how likely it is to find intelligent life advanced enough to be broadcasting signals into space in your galactic vicinity at the present time. The trick is that we don't have exact numbers for most of the terms, but the upshot is that all but the most conservative estimates turn up at least a few alien civilizations in our galaxy. A good introduction to the nitty-gritty of the equation can be found here (http://www.pbs.org/wgbh/nova/space/drake-equation.html).
- Hubble Image Gallery (http://hubblesite.org/gallery/): This might seem counter-intuitive, but there's just something about seeing these beautiful, colorful pictures that makes the Universe look like a friendlier place.
- Things Close to Home (http://www.nasa.gov/mission_pages/cassini/main/index.html and http://mars.jpl.nasa.gov/msl/): if you're feeling a little...a-claustrophobic still, take a gander at some of the neighborhood scenery. NASA's Cassini-Huygens and Curiosity missions are returning routinely gorgeous pictures of planets that are within our reach, our cosmic siblings. Cassini is focusing on Saturn and its moons (some of which are prime local candidates for life), and Curiosity is, of course, on Mars. Check out especially the skyline pictures from Curiosity, and think about how those things that look like low hills are mountains up to 5 miles high!
*Fun Census calculations: I used the 2011 ACS numbers for average commute time for the entire US. (while I have your ear, the American Community Survey recently had its funding axed in Congress; this seriously erodes the information we have about the state of our nation's populace. Go read about about the fight, it was all over major media sources.) This number was 25.3 minutes. I assumed 55 mph as a median driving speed, to factor in both highways and local traffic. This gives 23 miles commute, one-way. Double that for a day's trip, 46 miles. Now, multiply that by the traditional 5 day workweek and 50 weeks of work per year, and you get approximately 11,600 miles per year.
Wednesday, November 21, 2012
Mars News...Sort of
Might as well strike while the iron's hot with this story...if you can call it that yet. I posted it on my Twitter (click here) the other day, but no one reads that.
Everyone is excited because the lovely science-y types over at MSL announced -- well, that something very interesting is about to pop, but that they're checking their data a few more times before they'll announce it (click here). Apparently the SAM instrument (click here -- sorry, if I just code the link in-text, it's not visible) has turned up a discovery of some sort.
Now I'm going to pretend for a few minutes that I'm qualified to speculate on this, because I've been following this mission like nerds follow Joss Whedon. Also, I've actually done coursework on astrobiology, so I know a teensy bit more than the average news reader.
Background info first: the rover has been collecting soil samples on Mars. They scooped and then dumped out the first few, because they want to make absolutely sure that the samples aren't contaminated by anything Earth-originating. It would be pretty embarrassing to claim to find life and later realize that someone sneezed on the shovel (just kidding, they do insane amounts of decon work before it gets launched; there's bona fide international laws about contaminating other planets -- click here). Anyway, the first sample was actually deposited in the spectroscopy machine, and now they're saying they have a discovery.
Overview of Spectroscopy: it's...just really, really cool. Basically, you beam white light into an object and pass the light that comes out the other side through a kind of prism, separating it into its constituent colors. If you're doing emission spectroscopy, what you get looks like a multicolor bar code. If you're doing absorption spectroscopy, you get the opposite -- a rainbow bar with red light at one end and purple at the other, and black vertical lines in certain areas. In both cases, the lines are the fingerprints of elements. Different atoms absorb light of certain wavelengths, always. So those wavelengths, seen together, always point to that particular element. Depending upon the patterns of the lines (and in more sophisticated readings, how much light is absorbed at each wavelength), you can tell what chemicals compose the object you're looking at, without taking it apart, using nothing but light. It's incredible.
So, what do I think they've found? I bet they've found some sort of complex organic molecule, maybe an amino acid or two. The simpler molecules that life are based on (hydrocarbons and other organics) can be found in a surprising range of places in the Universe, from asteroids to nebulae. It seems like the more we look, the more we see that carbons and hydrogens just can't wait to bond into the things our cells are made of, with a little help from cosmic radiation and/or water. However, amino acids and proteins are much harder to form, and don't seem to happen without a lot more prodding (lots of electrical current, or RNA/DNA instructions -- which are proteins themselves, you can see the problem).
It's unlikely that they've found current life, with the amount of radiation that hits the topsoil there, and the lack of water. It's also unlikely that they found dead signs of life, since that would be hard to find on the surface after billions of years, and microfossils are annoying hard to confirm as such. I also think it's improbable, as some naysayers are predicting, that they're going to announce definitively that there is no life. That would be ridiculous to do from a single soil sample.
It would be nice for them to have found something that would make a great headline -- MARS LIFE FINALLY CONFIRMED. But my guess is that they found something that only other scientists and astrobiology nuts are going to be excited about, while science-column journalists for newspapers scratch their heads about how to phrase the real discovery. PREPARE FOR...Prerequisites for Life Tentatively Confirmed on Martian Surface. Shiny.
Everyone is excited because the lovely science-y types over at MSL announced -- well, that something very interesting is about to pop, but that they're checking their data a few more times before they'll announce it (click here). Apparently the SAM instrument (click here -- sorry, if I just code the link in-text, it's not visible) has turned up a discovery of some sort.
Now I'm going to pretend for a few minutes that I'm qualified to speculate on this, because I've been following this mission like nerds follow Joss Whedon. Also, I've actually done coursework on astrobiology, so I know a teensy bit more than the average news reader.
Background info first: the rover has been collecting soil samples on Mars. They scooped and then dumped out the first few, because they want to make absolutely sure that the samples aren't contaminated by anything Earth-originating. It would be pretty embarrassing to claim to find life and later realize that someone sneezed on the shovel (just kidding, they do insane amounts of decon work before it gets launched; there's bona fide international laws about contaminating other planets -- click here). Anyway, the first sample was actually deposited in the spectroscopy machine, and now they're saying they have a discovery.
Overview of Spectroscopy: it's...just really, really cool. Basically, you beam white light into an object and pass the light that comes out the other side through a kind of prism, separating it into its constituent colors. If you're doing emission spectroscopy, what you get looks like a multicolor bar code. If you're doing absorption spectroscopy, you get the opposite -- a rainbow bar with red light at one end and purple at the other, and black vertical lines in certain areas. In both cases, the lines are the fingerprints of elements. Different atoms absorb light of certain wavelengths, always. So those wavelengths, seen together, always point to that particular element. Depending upon the patterns of the lines (and in more sophisticated readings, how much light is absorbed at each wavelength), you can tell what chemicals compose the object you're looking at, without taking it apart, using nothing but light. It's incredible.
So, what do I think they've found? I bet they've found some sort of complex organic molecule, maybe an amino acid or two. The simpler molecules that life are based on (hydrocarbons and other organics) can be found in a surprising range of places in the Universe, from asteroids to nebulae. It seems like the more we look, the more we see that carbons and hydrogens just can't wait to bond into the things our cells are made of, with a little help from cosmic radiation and/or water. However, amino acids and proteins are much harder to form, and don't seem to happen without a lot more prodding (lots of electrical current, or RNA/DNA instructions -- which are proteins themselves, you can see the problem).
It's unlikely that they've found current life, with the amount of radiation that hits the topsoil there, and the lack of water. It's also unlikely that they found dead signs of life, since that would be hard to find on the surface after billions of years, and microfossils are annoying hard to confirm as such. I also think it's improbable, as some naysayers are predicting, that they're going to announce definitively that there is no life. That would be ridiculous to do from a single soil sample.
It would be nice for them to have found something that would make a great headline -- MARS LIFE FINALLY CONFIRMED. But my guess is that they found something that only other scientists and astrobiology nuts are going to be excited about, while science-column journalists for newspapers scratch their heads about how to phrase the real discovery. PREPARE FOR...Prerequisites for Life Tentatively Confirmed on Martian Surface. Shiny.
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