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Submission Summary: 0 pending, 39 declined, 97 accepted (136 total, 71.32% accepted)

Submission + - Tatooine was likely orbiting in the same plane as its twin suns

The Bad Astronomer writes: A new study by astronomers of binary stars shows that exoplanets orbiting them (circumbinary planets) will orbit in the same plane as the stars if the two stars are relatively close together. If the stars are farther apart, the planets may have a perpendicular (polar) orbit around them. This study looked at the protoplanetary disks of dust and gas around binaries to draw this conclusion. Extrapolating to fiction, this means Tatooine in Star Wars was coplanar with its host stars.

Submission + - Remember that 70-solar-mass black hole announced last week? Yeah, not so much.

The Bad Astronomer writes: Last week, scientists announced the discovery of a stellar-mass black hole with 70 times the Sun's mass, far heftier than theory predicts they can get. Within days, though, four separate papers have come out casting extreme doubt on the claim. They show that the data weren't processed correctly, and that the black hole is closer to Earth than first assumed, which changes the calculations and makes it a more normal 5 — 20 solar mass object.

Submission + - Nearby star is Sun's long-lost sibling

The Bad Astronomer writes: A nearby star, HD 186302, was almost certainly born from the same cloud of gas the Sun was 4.6 billion years ago. Astronomers have found it has an almost identical chemical composition as the Sun, is on a similar orbit around the Milky Way, and has the same age (within uncertainties). Interestingly, it's only 184 light years away, implying statistically many more such stars are waiting to be discovered.

Submission + - Supermassive black hole rocketing out of distant galaxy at 5 million mph

The Bad Astronomer writes: Astronomers have found a supermassive black hole barreling out of its home galaxy at 5 million mph. The 3 billion solar mass behemoth formed from the merger of two slightly smaller black holes after two galaxies collided and themselves merged. The resulting blast of gravitational waves is thought to have been asymmetric, causing a rocket effect which launched the resulting black hole away. It's currently 40,000 light years from the galaxy's core.

Submission + - Earth Gets Another Quasi-Moon 1

The Bad Astronomer writes: Astronomers have found a new asteroid, 2014 OL339, that is a quasi-moon of the Earth. Discovered accidentally earlier this year, the 150-meter asteroid has an orbit that is more elliptical than Earth's, but has a period of almost exactly one year. It isn't bound to Earth like a real moon, but displays apparent motion as if it did, making it one of several known quasi-moons.

Submission + - New Mars crater spotted in before-and-after pictures

The Bad Astronomer writes: The Mars Reconnaissance Orbiter spotted a new crater on the surface of Mars, and, using before-and-after pictures, the impact date has been nailed down to less than a day — it happened on or about March 27, 2012. The crater is 50 meters or so in size, and surrounded by smaller craters that may have been caused by smaller impacts due to the incoming meteoroid breaking up. Several landslides were spotted in the area as well, possibly due to the shock wave of the impact.

Submission + - Astronomers determine the length of day of an exoplanet

The Bad Astronomer writes: Astronomers have just announced that the exoplanet Beta Pic b — a 10-Jupiter-mass world 60 light years away -— rotates in about 8 hours. Using a high-resolution spectrometer and exploiting the Doppler shift of light seen as the planet spins, they measured its rotation velocity as 28,000 mph. Making reasonable assumptions about the planet's size, that gives the length of its day. This is the first time such a measurement has been achieved for an exoplanet.

Submission + - New supernova seen in nearby galaxy M82

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

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

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.

Submission + - Three new exoplanets seen in direct photographs

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

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

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.

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