The uncertainty of science: A new study suggests that the exoplanet orbiting the star Formalhaut that was supposedly imaged and then later theorized to be nothing more than a dust cloud might be a planet after all.
False alarm: The rock found on Sunday is not part of the meteor that fell over San Francisco last week.
The first mirror for the Giant Magellan Telescope has been completed.
This is the first of seven. It is also the largest single mirror ever polished, at 8.4 meters, or 27.5 feet across. When completed the GMT’s segmented mirror will be 25 meters across, or more than 82 feet.
The supermassive black hole in the center of the Milky Way is about to get a snack.
Update: The recently launched NuStar telescope in July detected its first flare from the central black hole (which by the way is called Sagittarius A* and is pronounced Sagittarius A-star). If the gas cloud produces any fireworks as it whips past the black hole in the coming year then NuStar should see it.
The first piece of a meteor that fell over San Francisco on Wednesday has been found.
The 2.2-ounce meteorite hit the roof of Rev. Kent and Lisa Webber on St. Francis Avenue on Thursday night, but they didn’t realize at the time what it was, according to Novato Patch.
Astronomers now have the technology to observe Io’s volcanoes erupt, from Earth.
More exoplanet news: The problems of Kepler.
The article outlines the status — both good and bad — of Kepler in its hunt for Earthlike exoplanets.
I have already reported on Kepler’s failed reaction wheel. It no longer has a backup and needs every reaction wheel it has to keep it pointed in so precise a manner. Thus, the loss of one more wheel will shut the telescope down.
However, I had not been aware that the scientists now need more than twice as much time, eight years instead of three, to do their work, because they have discovered that sunlike stars are far more variable than expected. To quote the article,
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Big news: Astronomers have discovered that the nearest star to the Earth, Alpha Centauri, has an exoplanet only slightly heavier than the Earth.
Alpha Centauri is actually a triple star system, with two sunlike stars in a tight orbit around each other and a third star far out orbiting them both. The exoplanet orbits one of the inner stars every 3.2 days.
More details from Nature here.
A review of the extraterrestrial solar systems found by Kepler shows that most are like our own, “flatter than pancakes.”
A planet with four suns, found by amateurs.
A super Earth, made of diamonds.
Astronomers also thought 55 Cancri e contained a substantial amount of super-heated water, based on the assumption that its chemical makeup was similar to Earth’s, Madhusudhan said. But the new research suggests the planet has no water at all, and appears to be composed primarily of carbon (as graphite and diamond), iron, silicon carbide, and, possibly, some silicates. The study estimates that at least a third of the planet’s mass — the equivalent of about three Earth masses — could be diamond. “By contrast, Earth’s interior is rich in oxygen, but extremely poor in carbon — less than a part in thousand by mass,” says co-author and Yale geophysicist Kanani Lee.
Has Voyager 1 already left the solar system?
New data from the spacecraft indicate that the historic moment of its exit from the solar system might have come and gone two months ago. Scientists are crunching one more set of numbers to find out for sure.
As it does every month, NOAA today posted its monthly update of the ongoing sunspot cycle of the Sun. This latest graph, covering the month of September, is posted below the fold.
Not only is the Sun’s sunspot production continuing to fizzle, it is fizzling even more than before.
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Want to buy a telescope? The world’s second largest infrared telescope on Mauna Kea is for sale.
The price is relatively cheap, $1.24 million. All that is needed is a private corporation eager to get some good publicity while contributing to the science of astronomy.
A star has gone supernova and astronomers get to see it from the very beginning, and even earlier!
The star had erupted several times before but had not produced a real supernova explosion. On September 26 it finally did so. Moreover, astronomers have images of the star prior to any eruption, information that until recently was not available for any supernovae.
Dizzy: Astronomers have discovered a star that circles the supermassive black hole at the center of the Milky Way in only 11.5 years.
This newly discovered star joins another that is 15 times brighter and has a 16 year orbit. The combined orbital data from both will allow astronomers to measure precisely the size of the black hole while also measuring the distortion of space caused by its intense gravitational field.
Astronomers have identified the same kind of minerals found in comets in our solar system in the dusty disk surrounding the nearby star Beta Pictoris.
The uncertainty of science: Using data from the Spitzer Space Telescope astronomers have narrowed the universe’s rate of expansion to about 74.3 kilometers per second per megaparsec.
The importance of this number, also called the Hubble Constant, is that it allows astronomers to extrapolate more precisely backward to when they believe the Big Bang occurred, about 13.7 billion years ago. It also is a crucial data point in their effort to understand dark energy, in which this expansion rate is actually accelerating on vast scales.
Back in 1995 a team led by Wendy Freedman, the same scientist leading the work above, announced that they had used the Hubble Space Telescope to determine the expansion rate as 80 kilometers per second per megaparsec. Then, the margin of error was plus or minus 17 kilometers. Now the margin of error has been narrowed to plus or minus 2.1 kilometers.
Do I believe these new numbers? No, not really. Science has nothing to do with belief. I do think this is good science, however, and that this new estimate of the Hubble constant is probably the best yet. I would also not be surprised if in the future new data eventually proves this estimate wrong.
This is a wonderful article, outlining (with video!) the present state of knowledge about the past, present, and future of our home galaxy.
