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Submission + - Earth-sized planet discovered in its star's habitable zone

Submitted by The Bad Astronomer
The Bad Astronomer writes: Astronomers have announced the discovery of Kepler-186f, a very nearly Earth-sized planet in its star's habitable zone. The planet is the fifth in a system of five orbiting a red dwarf star 500 light years away, and is located in the region where liquid water could exist on its surface. It's not know if this planet is Earth-like — that is, with water and air and the potential for life — but it's the closest we've yet seen where one could be like our own planet.

Submission + - Object seen in skydiver's helmetcam unlikely to be a meteorite 3

Submitted by The Bad Astronomer
The Bad Astronomer writes: The viral video showing what looked like a meteorite falling past a skydiver made quite a splash, with many people assuming it was true. However, further analysis shows that it's also perfectly consistent with being a small (1-3 cm) rock that fell out of the parachute itself, which is a far more likely explanation.

Comment Re:Ummm, probably not (Score 1) 142

by The Bad Astronomer (#46664743) Attached to: Skydiver's Helmet Cam Captures a Falling Meteor
That analysis was done here: http://norskmeteornettverk.no/... (it's not in English, but google translate does a decent job). He makes a distance estimate based on speed, which itself is based on the assumption it's a falling rock at terminal velocity. But the distance, speed, and time it takes to cross the FOV are related, and if you make a stab at speed you can get distance and vice versa.

Comment Re:Ummm, probably not (Score 1) 142

by The Bad Astronomer (#46663953) Attached to: Skydiver's Helmet Cam Captures a Falling Meteor
Yes, the apparent speed is the biggest argument against it being something packed in the 'chute, I'd think. If the skydiver were still decelerating hard after the parachute opened, the rock could appear to move rapidly, but even then it appears to come from farther away than the parachute. I'm still looking into this, and will have my own thoughts posted tomorrow on my blog.

Submission + - New supernova seen in nearby galaxy M82

Submitted by The Bad Astronomer
The Bad Astronomer writes: A new and potentially bright supernova was just discovered in the nearby galaxy M82. This is a Type Ia supernova, the catastrophic explosion of a white dwarf. It appears to be on the rise, and may have been caught as much as two weeks before peak brightness. It's currently already brighter than magnitude 12, and may get to mag 8, easy to see in small telescopes. The galaxy is less than 12 million light years away, so this may become one of the best-studied supernovae in recent times. Type Ia supernovae are used to measure dark energy, so seeing one nearby is a huge boon to astronomy.

Submission + - Exoplanet camera now online

Submitted by The Bad Astronomer
The Bad Astronomer writes: The Gemini Planet Imager is a camera that is designed to take direct photos of exoplanets, alien worlds orbiting other stars. In a test run last November it spotted the exoplanet Beta Pictoris b, a dusty ring around a nearby star, and even snapped a portrait of Jupiter's moon Europa. Up to now, only about a dozen exoplanets have been directly imaged; GPI is expected to find dozens more in the next few years.

Submission + - How astronauts took the most important photo in space history

Submitted by The Bad Astronomer
The Bad Astronomer writes: On December 24, 1968, the Apollo 8 astronauts saw the Earth rising over the limb of the Moon. The photo they took of this moment — dubbed Earthrise —has become an icon of our need to explore, and to protect our home world. NASA has just released a video explaining how the astronauts were able to capture this unique moment, which included a dash of both coincidence and fast teamwork.

Comment headline isn't quite correct (Score 5, Informative) 129

The headline as submitted isn't really correct. The planet is not the biggest found; there are several whose mass may be larger, like the exoplanets announced just last week (and this planet has 11 times the mass of Jupiter; we don't know its actual size). The real issue with HD 106906 b is that it is so far out from its parent star, much farther out than planets with that ass should form. Either it formed farther in and got tossed out (which is unlikely) or it formed where it was, which current theories say is difficult; usually objects forming that far out have much higher mass. I explain all this in my own blog post about it.

Submission + - Three new exoplanets seen in direct photographs

Submitted by The Bad Astronomer
The Bad Astronomer writes: Planets orbiting other stars are usually found indirectly (by blocking their stars' light or inducing a Doppler shift in the light as they orbit, for example), but direct images of exoplanets are extremely rare. However, using the 10-meter Keck telescope in Hawaii, astronomers have taken photographs of three nearby exoplanets, all young, massive, and hot. One may be massive enough to count as a brown dwarf, but the other two are more likely in the planet-mass range. All three are very far from their stars, which means they may have formed differently than the planets in our solar system.

Submission + - Chelyabinsk-sized asteroid impacts may be more common than we thought

Submitted by The Bad Astronomer
The Bad Astronomer writes: Using data from the Feb. 15, 2013 asteroid impact over Russia, scientists have determined that we may be hit by objects in this size range (10 — 50 meters across) more often than we previously thought, something like once every 20 years. They also found the Chelyabinsk asteroid was likely a single rock about 19 meters (60 feet) across, had a mass of 12,000 tons, and was criss-crossed with internal fractures which aided in its breakup as it rammed through the Earth's atmosphere.

Submission + - One in five Sun-like stars may have an Earth-like planet

Submitted by The Bad Astronomer
The Bad Astronomer writes: A new study, looking at over 40,000 stars viewed by the Kepler spacecraft, indicates that 22% of stars like the Sun should have Earth-like planets orbiting them — planets that are similar in size to our home world and with a surface temperature hospitable for liquid water. There are some caveats (they don't include atmospheric issues like the greenhouse effect, which may reduce the overall number, or at cooler stars where there may be many more such planets) but their numbers indicate there could be several billion planets similar to Earth in the Milky Way alone.

Comment Math. Sigh. (Score 5, Informative) 142

Folks- Please note a couple of math errors in the article (and in the headline I submitted here at /.). 1) The chance of it missing is 99.998%, and not 99.99998%. I misplaced a parenthesis when I did the math and wound up essentially getting 100 - 1/63000 instead of 1 - 1/63000. D'oh. 2) Also, the original circle I drew in the article was too big. This one makes me smile wryly: I first drew up the analogy as the circular cross-sectional area of a target region in space versus the cross-section of the Earth. Both are circles. However, a pixel is square! So my circle was too wide by a factor of the square root of pi, since the radius of the circle is the sqrt(area/pi). Put in 63,000 pixels for the area and the radius is 141. I corrected the article, sent a note to TPTB at Slashdot, and beg the forgiveness of math pedants everywhere. :)

Submission + - No, the Earth (almost certainly) won't be hit by an asteroid in 2032

Submitted by The Bad Astronomer
The Bad Astronomer writes: Last week, astronomers discovered 2013 TV135, a 400-meter wide asteroid that will swing by the Earth in 2032. The odds of an impact at that time are incredibly low — in fact, the chance it will glide safely past us is 99.99998%! But that hasn't stopped some venues from playing up the apocalypse angle. Bottom line: we do not have a good orbit for this rock yet, and as observations get better the chance of an impact will certainly drop. We can breathe easy over this particular asteroid.

Submission + - Saturn in all its glory

Submitted by The Bad Astronomer
The Bad Astronomer writes: On Oct. 10, 2013, the Cassini spacecraft took a series of wide-angle pictures of Saturn from well above the plane of the rings. Croatian software developer and amateur astronomical image processor Gordan Ugarkovic assembled them into a stunning mosaic (mirrored on Flickr), showing the planet from a high angle not usually seen. There's a lot to see in this image, including the rings (and the gaps therein), moons, and the planet itself, including the remnants of a monstrous northern hemisphere storm that kicked off in 2010. It's truly wondrous.

Submission + - Russian missile test seen and photographed by ISS astronauts

Submitted by The Bad Astronomer
The Bad Astronomer writes: It sounds like a scene from "Gravity": Astronauts aboard the International Space Station Thursday saw a weird, glowing cloud of light in the distance, most likely caused by a fuel dump or leaking fuel from a Russian missile launch. The extended life of a Topol missile was being tested in a ballistic launch to a test target in Kazakhstan, and the astronauts were able to take pictures of both the launch vapor trail and the glowing cloud. This event is similar to the eerie spiral lights seen over Norway in 2009 caused by a Russian missile launch as well.

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