My God--- It's Full of Planets!

I certainly picked an interesting time to take an intensive astronomy course.

Via David Brin, I hear that we've now found that our new space telescope Kepler has found 140 Earth-sized exoplanets. Kepler finds planets by detecting almost imperceptible 'winks' - the tiny amount of dimming that occurs each time a planet moves across the face of a star . . . 'Transits', as they are known, by terrestrial planets produce a small change in a star's brightness of about 100 parts per million, lasting for 2 to 16 hours. Information such as a planet's size and the extent of its orbit can be calculated from the amount of dimming, the length of time between 'winks' and the star's mass . . .

Sasselov said: ‘There is a lot more work we need to do with this but the statistical result is loud and clear and it is that planets like our own Earth are out there.

‘Our own Milky Way galaxy is rich in these kinds of planets.’

For the next stage of the mission the team will study all of the candidate planets and try and discern which of them have the right conditions for life.

Zero to 140 overnight! And, because of the method used, the only planets they could find were those that passed between their sun and us--- planets in other orbits would be invisible using this type of technology. So multiply that 1490 by, well, lots.

Meanwhile, on the freaker side of astronomy, the Hubble has spotted a blue "hypervelocity star" that has been flung out of the center of our galaxy by the supermassive black hole that lurks there, and is now zooming out of the galaxy at 1.6 million mpg.

Bye. See you next turn of the Wheel.

And in other news, astronomers have now found some super super super massive stars, 300 times the mass of our sun. Stars that big won't last long, but with the discovery of stars weighing between 150 and 300 solar masses, the study's findings raise the prospect of the existence of exceptionally bright, "pair instability supernovae" that blow themselves apart. These exploding stars fail to leave any remnants, and disperse up to ten solar masses of iron into their surroundings. A few candidates for such explosions have been proposed in recent years.

Time to stake your claim on the flying iron shrapnel! You've only got a few million years to do it.

I predict a really good season for space opera. Bunches of Earthlike planets, plus bizarro astronomical events to add the spice of cosmic weirdness. Let the scribbling begin!

Stellar Types

So I've been living and breathing astronomy for four whole days now, and it's producing conversations like this:

ME: I've been observing the Wal-Mart parking lot, and I've noted twelve Class O supergiant vehicles, fifteen Class B giant vehicles, eight Class G vehicles, and nine Class M dwarf vehicles.

CARRIE: What conclusion do you derive from your observations?

ME: Big pickup trucks and Wal-Mart have a powerful mutual attraction.

Watch the Skies!

While in Portales I got to admire Steve Gould's new iPad, which I have to say is a lovely, shiny toy that for the most part does nothing that other platforms can't do better and cheaper. It's an awkward size and my cargo pants would have to be completely redesigned if I were to carry one around. (And it won't run Flash, and because it doesn't have a phone you can't call for pizza, so what's the point, really?)

There was one app, though, that nearly had me writing a check to Steve Jobs for five hundred bucks.

It's a program that will show you whatever's in the sky directly behind the iPad.

So if you hold the iPad up to Scorpius, it will show the stars of Scorpius, an outline of the constellation, the other stars within the frame, and any planets that may be rambling past the scenery. You can tap on the planets and major stars and nebulae and galaxies and get a closeup view, along with a bunch of data.

It will work in the daytime. It will show you the stars on the other side of the sun or moon. It will look down through the Earth and show you the skies of another hemisphere. If you're stargazing, you'll be able to easily identify what you're looking at, or locate an object so that you can point your telescope at it. And you can dial down the intensity of the screen so it won't ruin your night vision.

But I didn't spend the five hundred bucks, so I can't tell you anymore than this.

This Just In: Solar System Tied Up With Ribbon!

Y'know, if you were watching Trek, and Mr. Spock turned to the captain and said, "There's a ribbon of mysterious energy surrounding the solar system," you'd just groan and mutter something about the series' cheezy made-up science.

Except it turns out there really is a ribbon of mysterious energy surrounding the solar system.

Next, we'll discover how to make dilithium.

For years, researchers have known that the solar system is surrounded by a vast bubble of magnetism. Called the "heliosphere," it springs from the sun and extends far beyond the orbit of Pluto, providing a first line of defense against cosmic rays and interstellar clouds that try to enter our local space. Although the heliosphere is huge and literally fills the sky, it emits no light and no one has actually seen it.

Until now.

NASA's IBEX (Interstellar Boundary Explorer) spacecraft has made the first all-sky maps of the heliosphere and the results have taken researchers by surprise. The maps are bisected by a bright, winding ribbon of unknown origin:

"This is a shocking new result," says IBEX principal investigator Dave McComas of the Southwest Research Institute. "We had no idea this ribbon existed--or what has created it. Our previous ideas about the outer heliosphere are going to have to be revised."

. . . One important clue: The ribbon runs perpendicular to the direction of the galactic magnetic field just outside the heliosphere, as shown in the illustration at right.

"That cannot be a coincidence," says McComas. But what does it mean? No one knows. "We're missing some fundamental aspect of the interaction between the heliosphere and the rest of the galaxy. Theorists are working like crazy to figure this out."

More of the story here.

Planets Found and Lost

News from the World O' Science:

We may have seen our first extra-galactic planet. Micro-lensing may have shown that a star in the Andromeda Galaxy has a planet six times the size of Jupiter.

The advantage of microlensing is that it works best for more distant objects, so it's ideal for planet hunting in other galaxies. In theory, it should be possible to see Earth-size objects in this way. The disadvantage is that microlensing is a relatively rapid, one-off event that lasts a few days at most. That makes observations difficult to verify.

It's hard to see individual stars like this, let alone planets. Astronomers have so far spotted only about a dozen stars in Andromeda in this way, and plans are afoot to search for lots more.

But get this: the light from one of these Andromedan stars showed a distinct variability that the discoverers attribute to an orbiting companion . . .

And (as Ralf pointed out elsewhere) a couple French astronomers have created a computer model of the next 5 billion years of our solar system's history. Result: Cosmic Catastrophe!

A number of computations resulted in Mercury's orbit collapsing and Mercury colliding with the Sun after about 4 Gyr. In a run where the minor axis was shrunk by 812 mm (32in), Mercury slammed into Venus just after 1.7 Gyr. In what the authors describe as their most interesting simulation—one where Mercury's axis was decreased by 468 mm (18.4 in)—Mars and Earth had a close encounter, passing within 794 km of one another.

Using this as an interesting starting point, the authors ran another series of 201 integrations where the semi-major axis of Mars was changed by up to 30 mm. Within 100 Myr of starting these integrations, five of the simulations resulted in Mars being ejected from the solar system. All of the remaining 196 cases resulted in various collisions between Earth, Mars, Venus, Mercury, and/or the Sun.

We'd better get off this planet in the next billion years or so, or else we're toast!