Geez, I hate to keep hitting this theme, but y’know what? It’s important.

Using a fleet of Earth-observing satellites, the European Space Agency is reporting that the ice in the Arctic circle is already retreating considerably, and will once again be below average in extent this summer. This has been going on for a few years now, which isn’t terribly surprising considering that global warming is real and that we keep seeing recent years tied or exceeding records as hottest years on record.

Here’s the map they made showing sea ice extent from June 1 to August 24, 2011:

Yikes. Back in 2007, the Northwest Passage became entirely navigable by sea (without using an icebreaker ship) for the first time in recorded history. It had already been thinning for years, but an icebreaker ship was still needed to get through all of it — that’s changed now.

Moreover, it’s not just that the extent — that is, the amount of area covered by the ice — has dropped, it’s also that it’s thinning, dropping in volume. The ice volume has decreased by unprecedented amounts as well recently.

What does this mean for the current Arctic summer?

"The minimum ice extent is still three to four weeks away, and a lot depends on the weather conditions over the Arctic during those weeks," says Leif Toudal Pedersen, a senior scientist at the Danish Meteorological Institute. "Whether we reach an absolute minimum or not, this year again confirms that we are in a new regime with substantially less summer ice than before. The last five summers are the five minimum ice extent summers on record."

[Emphasis mine.]

Just to be clear: it’s OK to question the science of global warming. It’s OK to question any scientific findings, as long as that questioning is done with good intentions and in good faith (so to speak). While poking around the web I found denier sites trying to confuse the issue of sea ice extent — for example, some talking about the navigability of the Northwest Passage as far back as 2000, but not mentioning you needed an icebreaker to do it.

As usual, the evidence here is pretty clear: temperatures are increasing, sea ice is going away, glaciers are retreating, ocean levels are rising, and all the while we’re dumping greenhouse gases into the atmosphere while the spin doctors whirl away.

It’s maddening. But it will continue, as surely as the Earth itself turns.

I’ve been scratching my head for a long time, trying to figure out why NASA hasn’t been taking the idea of preventing asteroid impacts more seriously. This idea has everything you’d want in a project: it’s cool (I mean, c’mon, we’re talking asteroid impacts!), it’s doable, it’s not terribly expensive, it’s already on the public’s mind thanks to Hollywood, and there’s always the eensy-weensy possibility that you might save all of humanity.

Yet, despite this, it’s been an uphill battle to get NASA to pay attention. While the space agency has been very good about supporting early detection programs, the support for a space mission to prevent an impact has been lacking. Of course, given their relatively small budget (<1% of the federal spending) I imagine taking on anything like this would be difficult.

So I’m pretty chuffed that the European Space Agency is looking into saving our collective skins. They’ve being studying the feasibility of a mission to test methods of asteroid impact mitigation, including a very very cool space mission they’ve dubbed Don Quijote (first proposed in 2002, and may launch sometime after 2020). It’s actually two separate spacecraft: one to impact a small near-Earth asteroid, and another to monitor the event carefully to see what happens, including how much the orbit of the asteroid was changed.

The idea here isn’t complicated: if we see an asteroid on an impact trajectory with Earth, we want to change the orbit so it doesn’t hit us. We could try blowing it up, but that’s actually a bad idea: at best it creates a lot of debris that can still smack into us, some of which may still be big enough to do us serious harm. So a better idea is to make sure it doesn’t hit us at all.

(more…)

This is what it looks like when you’re looking out a Soyuz window, leaving the International Space Station with a Shuttle Orbiter docked to it:

This amazing image was taken by European Space Agency astronaut Paolo Nespoli as he was being taken back to Earth. The Soyuz was only about 200 meters from the station when he captured this shot. He’s taken some of my favorite pictures from the ISS (like this, this, and this), and I’ll miss his keen eye behind the lens.

But, I imagine, not as much as he’ll miss being there. I wonder when he’ll get another chance to go up to space?

Image credit: NASA

The European Space Agency is sponsoring a contest: if you think comets are cool, tweet about them! The winner gets a trip to Darmstadt, Germany — ESA’s operating HQ — to celebrate 25 years of exploring comets.

There are rules, but they boil down to posting on Twitter about comets, using the "#coolcomet" hashtag, and providing an optional link to a non-text page (YouTube video, picture, etc.) that follows up. You have to be from a member country of ESA or the US to participate.

They are collecting all the tweets using TwapperKeeper, and you can see what others have done. They’re getting lots of entries, so if you want to try, I suggest being clever. Think about different aspects of comets, something unusual, and why they’re so interesting. The posts linked below might help get your unsublimated gases thawed.

Have fun! And if you win, send me a postcard from Darmstadt.

Image credit: Comet McNaught in the daytime from Chris North/Wikipedia

- Ten Things You Don’t Know About Comets
- Followup: Deep Impact crater on Tempel 1
- A comet creates its own snowstorm!
- Amazing close ups of comet Hartley 2
- Actually, if you’re a comet, it *is* easy being green

As recently promised, the European Space Agency’s Mars Express probe made a very close pass of the small moon Phobos, taking incredibly detailed pictures of the spud-shaped rock. Emily Lakdawalla, as always with planetary missions, has the what-fors with this event.

When it was a mere 111 km (66 miles) from the moon, Mars Express took this amazing image:

Click it for the full-res version is a whopping 7800 x 5200 pixel, 13 Mb TIF barsoomenated version. The detail is incredible, with features as small as 8 meters (roughly 25 feet across). Since Phobos is about 27 km (17 miles) long, that’s a lot of detail!

But as regular readers know, I have a thing for 3D red/green anaglyphs, and as the probe passed the moon naturally took stereoscopic images. The folks at ESA put two together to make this jaw-dropping 3D shot of Phobos:

Click it to get 3800 x 2600 pixel, 13 Mb TIF version. You really want to. If you have red/green glasses, this is one of the best anaglyphs from space you’ll see. I’ve never seen something stick out of my screen like this! Also, the details were so sharp that if I shake my head back and forth (like gesturing "no") I can actually see Phobos rotate a little bit, due to the change of positions of my eyes! That was new to me as well, and is very cool. it really solidifies the illusion that you’re seeing an object three-dimensionally.

Mars is an astonishing place, and it’s easy to forget how interesting its two moons are (the other is Deimos, which is smaller than Phobos). Their origins are still something of a mystery, and the surface features on Phobos are not totally understood either. (more…)

A few years back, astronomers discovered that some distant galaxies were blasting out vast amounts of infrared light, but were very faint in visible light, the kind we see. They termed these objects ULIRGs ("you-lurgs"), for Ultra Luminous Infrared Galaxies. The idea is that these galaxies are forming lots of stars, but there was so much dust choking the region that all the visible light was blocked. However, infrared light can pierce through the dust, so telescopes that detect IR can see them. Due to the physics of the situation, astronomers also figured there must be two populations of these galaxies; the ones they had found, and another that was (very) slightly warmer.

Well, they finally found some from that second group:

I know, they don’t look like much, do they? But you have to realize what you’re seeing here: those circled blobs of light are entire galaxies, with billions of stars, and they’re a staggering 11 billion light years away.

That’s really, really far. The Universe is only 13.7 billion years old, so we’re seeing these galaxies as they were just a few billion years after the entire Universe came into being. Not only that, but the amount of infrared light these galaxies are emitting is truly terrifying: in the infrared alone, they are blasting out a solid trillion times the Sun’s entire energy output.

A trillion! 1,000,000,000,000! That’s a whole lot of energy. And it comes from a whole lot of newborn stars, because these galaxies are cranking out stars at a rate 700 times that of our own Milky Way galaxy! The view inside those galaxies must be breathtaking; imagine being surrounded by the Orion Nebula everywhere you look. Wow.

What cracks me up about this too, is how they found them. The European Space Agency is using the orbiting Herschel Infrared Observatory to take a survey of galaxies in the IR. It’s finding a lot of them; in the picture above every dot you see is an infrared source, most likely a galaxy. And that’s a small section of the sky; on the right is an image of a bigger part of the survey. You need to click it and see it full-res to get a sense of how many freaking galaxies there are out there!

As far as astronomical discoveries go, this is another in a long series of steps needed to understand the Universe. I know that in your daily life this may not affect you much; you have other things on your mind, daily stresses and such. But you know what? While I go about my everyday business, in my mind I’m occupied by all the mundane and gross worries of life just like you are, just like everyone else is. But somewhere back there, in some part of my brain, there is knowledge that sits there… and every now and again, it makes itself known.

We can see galaxies a hundred billion trillion kilometers away! We know that stars are being born there, stars like the Sun, and they’re being born every day! If you were there, the sky would be a riot of red and green gas strewn in sheets and ribbons and shock waves and festooned with brilliant jewel-like stars everywhere you looked!

Those wonders are out there, and they’re real. That makes my life better, just knowing that.

Image credit: ESA/SPIRE/HerMES

- Herschel opens its eye
- Herschel eyes the infrared Southern Cross
- Chaos! Turbulence! Blowouts! Herschel!
- Record-breaking galaxy found at the edge of the Universe

The European Space Agency probe Rosetta is on its way to comet 67/P Churyumov-Gerasimenko (by way of asteroid 21 Lutetia next July), where it will arrive in May of 2014. It will be dropping a lander — the first ever attempted on a comet — and our knowledge of these fuzzy visitors will increase enormously.

But getting there is tough, and involves swinging by the Earth three times and Mars once. The final gravity assist will occur on November 13, with closest approach at 08:45 CET (over, roughly, the island of Java) when it’ll be moving past us at 13.3 km/sec (almost 30,000 mph). While it’s passing us by it will observe both the Earth and Moon, doing as much science as it can before heading out into deep space. Specifically, it will add its sensors to those already studying water on the Moon, as well as aurorae on Earth.

You can follow the action on the Rosetta blog. In fact, just the other day they posted this awesome shot of the Moon from Rosetta:

That was taken form a distance of 4.3 million kilometers (2.5 million miles), ten times the distance of the Moon from the Earth. The images as it gets closer will be even cooler.

So stay tuned! This is a very exciting mission, especially next year when it passes Lutetia! I can never see enough closeup pictures of asteroids.

Spacecraft image credit: ESA, image by AOES Medialab