Blogs / Bad Astronomy

Another planet orbiting a sunlike star has been directly detected by imaging… maybe. Here’s the image:

The possible planet orbiting Beta Pictoris is labeled. Click to embiggen. Image credit: ESO.

In this infrared image (taken at 3.6 microns, about 5 times the wavelength the human eye can see), the planet is the labeled point of light. Image processing techniques have negated the light from the star, revealing the glowing tell-tale of the planet. But, like the previous planet seen circling Fomalhaut, this image needs a bit more explanation!

The star in question is β (beta) Pictoris, or just β Pic. It’s about 64 light years away, and is far younger and a little bit hotter than the Sun. It has a disk of protoplanetary debris circling it, and from our angle we see it almost exactly edge-on, so the disk looks like a thick line bisecting the star. We’ve known about the disk since the 1980s.

But the disk is a little weird. There are actually two disks: the main one, and a much fainter, thinner one tilted a bit — you can just make out the edges of it in the picture, to the left of the upper part of the main disk, and to the right of the main disk in the lower part. The main disk is also not symmetric; it stretches more on one side of the star than the other. There are also some features in it, what look like they are rings of material (but we see them edge-on too, so they are difficult to discern). All of this points to a disrupting influence on the disk, and that implies a big ol’ planet in there somewhere.

The problem is finding it! The star is very bright (easily seen by the unaided eye in the southern hemisphere) and so any planet would be washed out. But astronomers using the Very Large (8 meter) Telescope have found something that is suspiciously like a planet. They very carefully subtracted the image of the star from itself (there are several techniques to do this) to reveal any faint blips that might remain, and voila! There it is.

It’s a strong signal, so it’s definitely real. But is it a planet? It might be a foreground or background object. The best way to know is to wait a year or two and take more images. If it is a planet, it will move across the sky along with the star. If it’s a galaxy, it won’t. Until we take more images, we won’t know for sure.

However, note that it is aligned with the disk! That’s a very strong (though circumstantial) piece of evidence that this truly is a planet. If I had to bet, I’d say it’s the real thing. If it is, it’s about 8 times the mass of Jupiter and about 8 times farther from the star than the Earth is from the Sun (somewhat less than the distance Saturn is from the Sun). The possible mass was determined using the brightness of the object; we know the star is about 12 million years old, and any planet that young will still be glowing from the heat of its formation — in this case, at about 1200 Celsius. It’s brightness and color depends on its mass, so the mass can be determined.

If this pans out, it will be the fourth planet directly imaged around a sun-like star. Incredible!

Remember, if it is a planet, it’s not Earth-like at all. It’s yet another super-Jupiter, and incredibly hot. But it’s a planet.

Let me reiterate what I said in my last post on this topic. Trying to see faint objects near stars in astronomical images is phenomenally tough work. I spent weeks working on Hubble data to do this very thing, and it’s mind-numbing, slow, meticulous, and difficult work. Subtracting a star’s light from the image is really hard (one of the best pieces of software I ever wrote figured out the exact center of a star’s image so another star’s image could be used to subtract it, in fact) and if you’re off by even a fraction of a pixel it won’t work. This potential planet is deep in the bright part of β Pic’s glow, yet they were able to see it clearly after processing, and that’s an achievement all by itself.

I spent many months hoping to end up with a picture like this, and it is fantastically cool to see this dream finally come true — especially with such a famous and well-studied target like β Pic. It’s a great milestone, and my congratulations to astronomer Anne-Marie Lagrange and her team who were able to tease out this prize!

I was recently at the James Randi Educational Foundation for a meeting, and while I was there I was presented with a large box. Inside said box, and in fact stacked up next to it, were over 50 copies of my book, Death from the Skies! So, pen in hand, I signed each and every one of them.

This is a photo from an older batch; the ones I just signed don’t have the sticker, just my name. Those are Randi’s hands, if you’re wondering.

If you’re looking for an autographed copy of the book — because the holidays are right around the corner, and nothing says "Merry Christmas!" like reading about a giant asteroid impact — then head on over to the JREF store and grab yourself one (they’re $6 off cover price). Copies are limited! And so’s your time: in 10³⁷ years, all the protons in the book will have decayed. So hurry!

UPDATE: CTV news has some pretty spectacular footage on their website.

News flashes are coming in (like from the Calgary Herald and The Edmonton Sun) that a very bright fireball lit up the skies in Alberta and Saskatchewan, Canada around 5:30 p.m. local time on Thursday. There are reports of a loud boom as well, meaning whatever it was got low enough to where air was thick enough to transport sound. There are several reports that it hit, but I always remain skeptical of those: when a meteor drops to the horizon it looks like it hits, but meteors very rarely do. But given how bright this one was (judging from the reports) it’s possible a piece or several pieces made it down. However, it also sounds like this was pretty remote territory, so we may not know for a while.

If you hear anything new, leave a comment here. If you saw it, then report it to the Meteorite and Impacts Advisory Committee to the Canadian Space Agency.

Tip o’ the Whipple Shield to Dan Abal and Tom Cochrane.

NASA is looking for a name for the next Mars rover, officially called the Mars Science Laboratory. They’ve decided to have a contest, and it’s open to school children up to 18 years of age.

The rovers so far (Sojourner, Spirit, Opportunity) have all had serious names, so I doubt they’ll go for Marvin, which would really just be perfect. How about Wells? I suppose John Carter is out. Ray Walston?

Of course, given how over-budget MSL is, and how it’s threatened other missions, they might want to name it Gilligan. Somehow, I doubt they’d go for that, either!

Anyway, if you’re a teacher or a school kid, check that site out and give it some thought. Your idea may wind up traveling millions of kilometers to another planet, and that’s pretty cool.

In the next weird thing found on — or below — the Red Planet, a ground-penetrating radar on board the Mars Reconnaissance Orbiter has found vast glaciers under the rocky surface. These glaciers are at the bases of mountains and cliffs, and are covered with rubble that may be protecting them from sublimating away. The even cooler thing is that these are at lower latitudes (nearer the Equator) than ever seen before.

“Altogether, these glaciers almost certainly represent the largest reservoir of water ice on Mars that is not in the polar caps,” said John W. Holt of the University of Texas at Austin, who is lead author of the report. “Just one of the features we examined is three times larger than the city of Los Angeles and up to one-half-mile thick. And there are many more. In addition to their scientific value, they could be a source of water to support future exploration of Mars.”

This older image shows a glacier that flowed from one Martian crater at the base of a mountain to another crater. Courtesy ESA/DLR/FU Berlin (G. Neukum).

I still advocate going to the Moon for a while before heading off to Mars, but Mars does have one big advantage: that water locked up in the glaciers is not that hard to tap into. It can be used for drinking, farming, breathing, and even as protection from solar radiation (the hydrogen in water makes a pretty good radiation shield).

These underground glaciers also answer a question that’s puzzled scientists for years: the existence of aprons, or gently sloped regions surrounding tall features on Mars. Now it seems clear that the ice at the base of these cliffs and mountains lubricated rubble descending from higher up, so instead of getting big piles, the rubble forms a smoother decline. The radar reflections from aprons indicates they are indeed a thin layer of rubble on top of thicker ice.

We’ve known for decades that Mars has water ice. What we’re learning now is the extent of it, how deep it goes, how it’s placed across the surface, and even how wet Mars was in the past. All of this builds us a picture of a once-dynamic planet, and one that still has lots of surprises waiting for us, literally just below the surface.

If you aren’t regularly looking at The Big Picture by now, than I don’t think I can help you anymore! It’s a fantastic collection of themed high-resolution pictures hosted at the Boston Globe.

A few days ago, the theme was microscopy. All I can say is: "THEM!"

Shoot the antennae! He’s helpless without them!

Actually, there are several pictures in that series that will haunt my dreams. There is something incredibly creepy about little teeny things seen through an electron microscope.

[shudder]

During the 10-day long voyage to the Galapagos Islands in August sponsored by the James Randi Eeducational Foundation, we took along a copy of The Voyage of H.M.S. Beagle, Darwin’s diary of his ground-breaking trip 150 years ago. Some smart cookie asked all of us to sign the book, and now that autographed copy is being auctioned! It has signatures by Randi, me, PZ Myers, George Hrab, and a whole lot more. The auction winner will also get a signed photo of Randi posing next to a Galapagos tortoise.

This is a pretty cool auction, and the proceeds will go toward a scholarship to help people attend the premier critical thinking conference The Amaz!ng Meeting 7, which will be in Las Vegas on July 9-12, 2009. We’re working on the speaker line-up and it’s already looking, well, amazing. So bid on the book and help some deserving person attend the meeting!