Stories tagged Earth and Space Science

May
31
2012

Crash!: This illustration shows a stage in the predicted merger between our Milky Way galaxy and the neighboring Andromeda galaxy, as it will unfold over the next several billion years.
Crash!: This illustration shows a stage in the predicted merger between our Milky Way galaxy and the neighboring Andromeda galaxy, as it will unfold over the next several billion years.Courtesy NASA; ESA; Z. Levay and R. van der Marel, STScI; T. Hallas; and A. Mellinger
I think this is really interesting - below is straight from a release from NASA.

NASA astronomers announced Thursday they can now predict with certainty the next major cosmic event to affect our galaxy, sun, and solar system: the titanic collision of our Milky Way galaxy with the neighboring Andromeda galaxy.

The Milky Way is destined to get a major makeover during the encounter, which is predicted to happen four billion years from now. It is likely the sun will be flung into a new region of our galaxy, but our Earth and solar system are in no danger of being destroyed.

"Our findings are statistically consistent with a head-on collision between the Andromeda galaxy and our Milky Way galaxy," said Roeland van der Marel of the Space Telescope Science Institute (STScI) in Baltimore.

The solution came through painstaking NASA Hubble Space Telescope measurements of the motion of Andromeda, which also is known as M31. The galaxy is now 2.5 million light-years away, but it is inexorably
falling toward the Milky Way under the mutual pull of gravity between the two galaxies and the invisible dark matter that surrounds them both.

"After nearly a century of speculation about the future destiny of Andromeda and our Milky Way, we at last have a clear picture of how events will unfold over the coming billions of years," said Sangmo Tony Sohn of STScI.

The scenario is like a baseball batter watching an oncoming fastball. Although Andromeda is approaching us more than two thousand times faster, it will take 4 billion years before the strike.

Computer simulations derived from Hubble's data show that it will take an additional two billion years after the encounter for the interacting galaxies to completely merge under the tug of gravity and reshape into a single elliptical galaxy similar to the kind commonly seen in the local universe.

Although the galaxies will plow into each other, stars inside each galaxy are so far apart that they will not collide with other stars during the encounter. However, the stars will be thrown into different orbits around the new galactic center. Simulations show that our solar system will probably be tossed much farther from the galactic core than it is today.

To make matters more complicated, M31's small companion, the Triangulum galaxy, M33, will join in the collision and perhaps later merge with the M31/Milky Way pair. There is a small chance that M33 will hit the Milky Way first.

The universe is expanding and accelerating, and collisions between galaxies in close proximity to each other still happen because they are bound by the gravity of the dark matter surrounding them. The Hubble Space Telescope's deep views of the universe show such encounters between galaxies were more common in the past when the universe was smaller.

A century ago astronomers did not realize that M31 was a separate galaxy far beyond the stars of the Milky Way. Edwin Hubble measured its vast distance by uncovering a variable star that served as a "milepost marker."

Hubble went on to discover the expanding universe where galaxies are rushing away from us, but it has long been known that M31 is moving toward the Milky Way at about 250,000 miles per hour. That is fast enough to travel from here to the moon in one hour. The measurement was made using the Doppler effect, which is a change in frequency and wavelength of waves produced by a moving source relative to an observer, to measure how starlight in the galaxy has been compressed by Andromeda's motion toward us.

Previously, it was unknown whether the far-future encounter will be a miss, glancing blow, or head-on smashup. This depends on M31's tangential motion. Until now, astronomers had not been able to measure M31's sideways motion in the sky, despite attempts dating back more than a century. The Hubble Space Telescope team, led by van der Marel, conducted extraordinarily precise observations of the sideways motion of M31 that remove any doubt that it is destined to collide and merge with the Milky Way.

"This was accomplished by repeatedly observing select regions of the galaxy over a five- to seven-year period," said Jay Anderson of STScI.

"In the worst-case-scenario simulation, M31 slams into the Milky Way head-on and the stars are all scattered into different orbits," said Gurtina Besla of Columbia University in New York. "The stellar populations of both galaxies are jostled, and the Milky Way loses its flattened pancake shape with most of the stars on nearly circular orbits. The galaxies' cores merge, and the stars settle into randomized orbits to create an elliptical-shaped galaxy."

The space shuttle servicing missions to Hubble upgraded it with ever more-powerful cameras, which have given astronomers a long-enough time baseline to make the critical measurements needed to nail down
M31's motion. The Hubble observations and the consequences of the merger are reported in three papers that will appear in an upcoming issue of the Astrophysical Journal.

May
29
2012

Plastics!
Plastics!Courtesy IonE
This is a couple weeks old, but I just noticed that the University of Minnesota's Institute on the Environment (one of the Science Museum's partners on the Future Earth exhibit) has posted another "Big Question" video. These are short, fun videos that cover some of the challenges humans will be facing in the coming decades. This one is about plastics, and whether we can make them sustainable.

Anyway, here you are:

(And for more on the subject, check out Science Buzz posts on plastics, plastic, and sustainability.)

May
24
2012

So it's true?: Not necessarily the moon thing. The other part.
So it's true?: Not necessarily the moon thing. The other part.Courtesy Thomas Fowler and OZinOH
What does that title even mean?! I don’t know! Yakov Smirnoff stopped making jokes when I was a baby!

In Russia, phone dials you! In Russia, self-tanner applies you! In Russia, wife buys you! They’re all just meaningless words without the code!

Could it be that Russia has plans to establish a permanent base on the moon? Could that be? I mean, on one hand, my conception of Russia is more or less summed up by an imagined scene in which an old woman and a bear fight over a wilted cabbage. The old lady has a broom … but the bear wants the cabbage too! Does that sound like a space-colonizing nation?

Then again, the mighty USA has been hitching rides into space on Russian rockets for a while now, since we apparently decided that spaceships weren’t something we wanted to buy.

So who knows? Maybe Russia will put a permanent base on the moon. (Or maybe China or Japan will.) Maybe the US will go to an asteroid or to Mars. Maybe, in Russia, asteroid will go to you. Or maybe it’s all just astronaut pillow talk.

May
18
2012

Wheeeeeee!: I'm a computer generated mockup, but I feel like I'm flyiinggggggg!
Wheeeeeee!: I'm a computer generated mockup, but I feel like I'm flyiinggggggg!Courtesy FlyingSinger
The Flight of Dragons? Anyone? Anyone? 1982 Rankin/Bass? I don't know. I thought it was pretty dope when I was 5, but I felt that way about a lot of stuff.

Whoops! Got sidetracked there! What I meant to say is that the private spaceflight company, SpaceX, will be launching their Dragon capsule tomorrow, to rendezvous with the International Space Station. Assuming all goes well. (And let's be a glass-half-full crowd and just assume that, eh?)

The unmanned Dragon capsule will be hurled into the heavens on SpaceX's 2 stage Falcon 9 rocket. When it gets to the Space Station, it will do a practice docking run. (This whole thing is kind of a trial run, although Dragon will have some cargo for the astronauts aboard. Just for fun, I guess.)

You'll know if everything went off without a hitch, because your life will be changed forever, or something.

The Flight of Dragons!

May
04
2012

Do you want my advice, guys?: You should go get some asteroids.
Do you want my advice, guys?: You should go get some asteroids.Courtesy Blue Marble
It isn’t good to confuse great-grandparents. For one, they’re often dead, and confusing them involves meddling in forces that are best be left alone. Or, in the case that they aren’t dead, they’ve had a busy life parenting, grand-parenting, and great-grand-parenting, and they deserve a little more from you than a bunch of confusing jibber-jabber about meteorites, or whatever you just said.

So if your great-grandparents are still alive (not dead), please do them a favor, and just make something up as you pretend to read the rest of this post out loud to them. Their side of the 20th century probably did not equip them for this sort of thing:

Asteroid mining! After thousands of years of scratching through the dirt, wearing our finger bones to stumps in near-futile attempts to uncover the shiniest bits of gravel, humanity will finally ascend to the stars, and scratch through the dirt of asteroids in the noble effort to find the shiniest astro-gravel. And it will make us richer than our wildest dreams!

Or it will make the billionaires behind the project as rich as their everyday dreams.

Here’s the story: a bunch of billionaires and their spunky sidekick, James Cameron (who is a film director, and worth only about 700 million dollars—practically destitute), looked out over their Earth and wept, because there was nowhere left to conquer. It was maybe the worst Unicorn Polo Sunday ever. But then James Cameron, lying on his back after slipping on a banana peel (that’s sort of his role in the group), looked up at the sky and said, “Hey, gang! I have an idea! Maybe there’s more up there for us!”

Well, the members of the Billionaires’ Club would like to say that they took lil’ Jim’s suggestion there and then, but, frankly, they had heard a lot of nonsense out of his pinched little mouth over the years, and they had long ago learned to tune him out. (Xenomorph this, Titanic that, look at my submarine, what about another killer robot, what has my ex wife done that’s so special?—they had heard it all before.)

But at some point Cameron’s seemingly childish remark filtered its way through the buzz of billionaire preoccupations (stocking up on mansion wax, plans to swim Scrooge McDuck style through gold coins, and which would be the best ocean to buy) and lodged itself in the billionaires’ minds, where it incubated, hatched, and chewed its way deeper into their brain tissue.

And thus Planetary Resources was born. With a group of billionaires behind it (including Larry Page, CEO of Google, power of earth; Eric Schmidt, executive chairman of Google, power of fire; Charles Simonyi, Microsoft guy, power of water; and Ross Perot Junior, son of diminutive former presidential candidate, power of heart) and James Cameron as an advisor (because he has made at least two movies about space, and has been in a submarine), Planetary Resources plans to scan thousands of near-Earth asteroids for precious metals and water, and then send robotic probes to pull the asteroids into a convenient location, and then smash them up for their goods.

Why? For a few reasons. Partly because it’s awesome, and you need to be super rich to do it, and they’re exactly that rich. But also because lots of these asteroids are full of precious, useful metals—billions and billions of dollars worth in even small asteroids. And asteroids with lots of ice in them could basically be turned into gas stations for spaceships. Water is pretty easily split into hydrogen and oxygen, which we can use for rocket fuel, and having fuel waiting in space is way, way, way cheaper than bringing it there from Earth. So making fuel available in space could potentially lower the cost of exploring our solar system quite a bit.

The plan is to launch a fleet of (relatively) cheap asteroid-scanning telescopes some time in the next two or three years to identify near-Earth objects that both contain enough valuable materials, and are near enough to Earth (the hope being that they would be as easy or easier to reach than the moon). In the next decade, or somewhere in that neighborhood anyway, larger spacecraft would be launched that could capture the asteroids. Harvested materials could then be processed in space, or sent back to the planet. All operations would be unmanned, as having human pilots or minors would make everything significantly more expensive and risky.

In the week or so since the Planetary Resources made their announcement, it seems like most of the professional reactions I’ve read have treated the plan pretty seriously—while it requires a large investment, it’s not unrealistic.

I have to admit, it’s kind of an exciting plan. And it will keep the billionaires occupied for a little bit, which is good. Because we all know what happens when a billionaire gets bored.

(It didn’t make sense to me either. You think your great-grandparents are going to get it?)

May
02
2012

Cumulative impact by humans on the ocean
Cumulative impact by humans on the oceanCourtesy National Center for Ecological Analysis and Synthesis
One of the great extinctions in Earth history occurred 252 million years ago when about 95 percent of all marine species went extinct. The cause or causes of the Great Dying have long been a subject of much scientific interest.

Now careful analyses of fossils by scientists at Stanford and the University of California, Santa Crux offer evidence that marine animals throughout the ocean died from a combination of factors – a lack of dissolved oxygen, increased ocean acidity and higher water temperatures. What happened to so dramatically stress marine life everywhere?

Geochemical and fossil evidence points to a dramatic rise in the concentration of carbon dioxide in the atmosphere, which in caused a rapid warming of the planet and resulted in large amounts of carbon dioxide dissolving into the ocean and reacting with water to produce carbonic acid, increasing ocean acidity. The top candidate for all this carbon dioxide? – huge volcanic eruptions over thousands of years in what is now northern Russia.

Why should the Great Dying be of more than just academic interest? Humans currently release far more carbon dioxide into the atmosphere than volcanoes and we are releasing carbon dioxide into the atmosphere at a rate that greatly exceeds that believed to have occurred 252 million years ago. The future of Earth’s oceans will be determined by human decision making, either by default or by design. What do we want our future ocean to be?

Apr
13
2012

The ATV-2: The astronauts filled it with trash, and then burned it. But, to be fair, they probably ate that trash several times before they finally tossed it.
The ATV-2: The astronauts filled it with trash, and then burned it. But, to be fair, they probably ate that trash several times before they finally tossed it.Courtesy NASA
I am adding a’s to the end of words to make them sound a little like “NASA.” Try it. It’s funa.

Anywaya, I thought I’d run a little idea I had by y’all.

I got trash. Who doesn’t? You use stuff, you make trash, and it just piles up. Under your couch, in the freezer, on top of the cat … what are you supposed to do with it? Put it on the curb? I guess, but what’s exciting and easy about that? So, my idea—which I got from the world’s various space agencies—is to take my trasha up to the roofa of my apartment building (three stories!!) and just drop it. If I’m at all accurate in my understanding of acceleration and atmospheric friction, all those Sears catalogues, plastic cups, and mouse skeletons should burn up before they hit the ground.

I mean, it’s what NASA, the European Space Agency and all of their ilk do, and it seems to work for them. Take the ESA’s recently launched ATV-3 (Automated Transfer Vehicle-3). The large, unmanned space capsule will deliver about 7 tons of cargo to the International Space Station (a few hundred pounds of food, water and oxygen, and about 6.5 tons of candy), stay docked for 4 to 6 month while the astronauts use it like a missing roommate’s walk-in closet, and then, once it’s completely full of trash, it will detach, fall towards Earth, and incinerate in the atmosphere. Easy peasy. Easya peasya.

Despite it being what I think is an elegant solutiona to waste accumulationa, there are plenty of folks out there, who may or may not be smarter than hundreds of NASA systems engineers, that believe this proves that astronauts are the worst recyclers ever. To this, I have three things to say:

1) You’re no fun.
2) Think about the fuel it takes to get those tons of junk into space. You’re worried about the waste that happens after that?
3) Wrong! In a lot of respects, astronauts on the ISS are the best recyclers in the histories of re and cycling.

See, here’s the thing about #3: astronauts may dump their candy wrappers, dead pets, banana peels and old undies (JK, they wear those undies for months) into a fiery and unforgiving atmosphere, but there’s a lot of stuff that they re-use again and again that you’d never even think of. Air, for one. And water.

When you’re breathing, farting, sweating and peeing for months on end in an airtight box floating in space, and a fresh glass of water costs between $10,000 and $15,000 for delivery, you have to be clever.

And the engineers of the ISS are clever! Consider the Environmental Control and Life Support System. Astronauts, like most of us, breath out poisonous carbon dioxide, fart out poisonous methane and sweat out poisonous ammonia. ECLSS filters out all of that to produce fresh air again. The system also splits water molecules apart to create breathable oxygen, and reclaims moisture from urine and other waist to produce more water for drinking (or ultimately breathing). I don’t know about you, but I rarely save my farts, sweat, breath and urine, much less reuse them.

All things considered, I think the ISS has a pretty sweet setup figured out. A two hundred and fifty mile trash drop-n-burn (awesome), and a system that can recycle pretty much anything that comes out of your body (also awesome). The rest of us should be so luckya.

Apr
10
2012

Atmospheric carbon dioxide concentration during the past 417,000 years
Atmospheric carbon dioxide concentration during the past 417,000 yearsCourtesy Wikipedia Commons
Skeptics of human-induced climate change have long pointed to a lag between an increase in temperature and a rise in atmospheric carbon dioxide at the end of the last Ice Age as suggesting that carbon dioxide is an effect of rising temperatures, not a cause. This lag, however, was based on evidence from only one place on Earth - ice core records from Antarctica.

A much more extensive study of paleo-temperature records from 80 sites around the world just published in Nature reveals that global temperature increases followed rises in the carbon dioxide concentration in the atmosphere. Carbon dioxide is a heat-trapping gas that can drive climate change. This study greatly substantiates climate scientists who point out that the enormous quantities of carbon dioxide that human activities are putting into the atmosphere will result in dramatic changes in global climate if they are not curtailed.

Mar
31
2012

Smear campaign: climate scientist relates his own experience from anti-science attack
Smear campaign: climate scientist relates his own experience from anti-science attackCourtesy CECAR - Climate and Ecosystems Change Adaptation R (adapted by Mark Ryan)
Several months back there was a lot of hoopla revolving around the so-called "Climategate" scandal. Climate scientists' emails were hacked, posted online and taken out of context as they were disseminated around the internet and through the news channels. Some researchers were charged with manipulating climate data to bolster their own point of view, and indignant investigations were launched against them. As the story fermented in the media, the blogosphere, and political circles, it grew into an over-inflated bag of hot-air. But, eventually, the truth prevailed, and those accused were exonerated by the facts. Michael Mann, a climate change researcher at Pennsylvania State University, was one of key figures in the "scandal", and has written (both here and in a new book) about his experience dealing with the kind of smear campaign that was hurled his way. He terms it the "scientization" of politics. It's involves some of same anti-science tactics used by the tobacco industry and creationists: mainly to cast doubt on the facts, and fabricate controversy where there is none.

Michael Mann at CNN.com

Feb
10
2012

I'm not complaining: But astronaut ice cream is old news. I need new gifts all the time.
I'm not complaining: But astronaut ice cream is old news. I need new gifts all the time.Courtesy Raiden256
I like to think of myself as a fair man.

With this in mind, I try to live my life under two basic philosophies: an eye for an eye, and you scratch my back, I’ll scratch yours. Sometimes I mix and match those ideas, but the essential thing is that my life is a series of reciprocated acts of scratching and eye gouging, and I think I’m better off for it. So, to make sure I’m being fair, I often find myself asking, “What have you ever done for me?”

Like, hey, Mom, what have you ever done for me? Birth? Well that was probably an accident. And what have you done for me lately?

Oh, hello, stranger. You want me to call the police? Maybe, but what have you ever done for me? Because from where I stand, all I think you’ve ever done for me is ruin my walk with your crying, and I’m on a 450-minute calling plan. I need those minutes for prank phone calling the animal shelter.

Why, sure, doctor, I’d love to pay you. But what have you ever done for me? You took that worm out of my eyeball? That’s pretty good, but I don’t know if it’s $2500 good. Here’s $37.25, and let’s call it square.

And so on. It works out pretty well, I think. Obviously it best applies to direct interactions, but I believe it’s reasonable to apply it to all things, which is why I spend most of my free time making lists of things (e.g. pineapples, leather, Gorbachev, Roman numerals, NASA, whispering, stickiness, shoe, minty, etc.) and then examining just what each item has done for me, so that I can better understand the balance of our relationship. As you may have guessed, I’m currently on “NASA.”

And so … NASA: what has it ever done for me?

My initial thought was, “very little.” I mean, it’s not that I don’t appreciate space ships and moon men, and all that. It has all been very inspiring. But, NASA, what have you done for me lately? I’ve never been given the chance to take a crack at microgravity, or to punch someone wearing a spacesuit in the stomach while wearing a spacesuit myself. Those are the kinds of things that could pull NASA up from the eye-plucking category into the back-scratching category, but they just haven’t happened.

Well, imagine my surprise when I saw this: NASA’s “Spinoff” page. Spinoff is basically NASA’s way of saying, “here’s what we’ve done for you, you ungrateful little punk.” I don’t like being spoken to that way, even when I’m the one who invented the less than cordial paraphrasing, but they and I have a point. Spinoff is about all the ways that NASA science makes it into the lives of norms—not just inventions like Tang (which, as it happens, NASA didn’t actually invent), but technologies that directly impact our everyday lives, and that create thousands of jobs and billions of dollars. It’s difficult to fully quantify the benefits from NASA tech, but NASA estimates that technologies featured in Spinoff since the year 2000 have saved about 12,000 lives, and extended or enhanced 86 million more; that efficiency engineering developments have saved companies about $6.2 billion; that NASA partners have created about 9,200 jobs; and that agency partner companies have generated $1.2 billion in revenue with the help of NASA technology.

I’m not going to list individual developments here because there are just tons of them, and because I’m super lazy, but they range from more aerodynamic semi-trucks, to better fire-extinguishing systems, to advances in energy efficiency, to … well, right, tons of stuff. But I would highly recommend taking a look at NASA’s 2011 Spinoff book, which can be found (free) in PDF form here. It’s over 200 pages, but it’s an entertaining and informative skim (or an informative read, I guess, but what has reading ever done for me?)

Check it out—it’s pretty interesting, and it should help you avoid a lengthy, crushing comeback when you ask NASA what it’s done for you lately. (That can be very embarrassing.)