An detailed analysis of the tumbling of the asteroid Apophis, detected by radar observations in January, suggests it will be easier to predict the asteroid’s orbit in the future.

The sky isn’t falling: A detailed analysis of the tumbling of the asteroid Apophis, detected by radar observations in January, suggests it will be easier to predict the asteroid’s orbit in the future.

The gentle but persistent nudging [of the Yarkovsky effect] arises when sunlight is absorbed by a rotating object and then reradiated as heat in some other direction. In particular, if Apophis were spinning retrograde (opposite the way Earth does), then over time its orbit would change in a way that increases the chance of impact in 2036. But now we can rest easy, because Apophis appears to be tumbling as it orbits the Sun. That’s the conclusion reached by a team of telescopic observers who monitored the asteroid’s light curve as it passed near Earth in January. Apophis is spinning around two axes at the same time, implying that any Sun-warmed surfaces are radiating heat in all directions, not just one in particular.

It is very difficult to measure the Yarkovsky effect, thus making it very difficult to precisely calculate the orbits of many near Earth asteroids. In the case of Apophis, however, it appears the astronomers have gotten a good handle on the problem.

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Hubble has taken a spectacular close-up image of the Horsehead Nebula.

A horsehead of another color: Hubble has taken a spectacular close-up image of the Horsehead Nebula.

Also, if you want to find out exactly how powerful Hubble is in comparison with both ground-based and other space telescopes, check out the video provided by this press release for the new images by the Herschel Space Telescope of the Horsehead Nebula that were also released today. Herschel, which works in the far-infrared, produces good data and information that Hubble cannot, but its imagery cannot compare.

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Using Kepler astronomers have found a solar system with five terrestrial-type planets, with two in the habitable zone.

Eden? Using Kepler astronomers have found a solar system with five terrestrial-type planets, with two in the habitable zone.

Using observations gathered by NASA’s Kepler Mission, the team, led by William Borucki of the NASA Ames Research Center, found five planets orbiting a Sun-like star called Kepler-62. Four of these planets are so-called super-Earths, larger than our own planet, but smaller than even the smallest ice giant planet in our Solar System. These new super-Earths have radii of 1.3, 1.4, 1.6, and 1.9 times that of Earth. In addition, one of the five was a roughly Mars-sized planet, half the size of Earth. …

The two super-Earths with radii of 1.4 and 1.6 Earth radii orbit their star at distances where they receive about 41% and 120%, respectively, of the warmth from their star that the Earth receives from the Sun. The planets are thus in the star’s habitable zone; they have the right temperatures to maintain liquid water on their surfaces and are theoretically hospitable to life.

Theoretical modeling of the super-Earth planets, Kepler-62e and Kepler-62f, suggests that both could be solid, either rocky–or rocky with frozen water.

This is big news. Additional info can be found here and here.

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A private company tells the IAU to bug off!

A private company tells the IAU to bug off about who has the power to name things in space!

Uwingu affirms the IAU’s right to create naming systems for astronomers But we know that the IAU has no purview—informal or official—to control popular naming of bodies in the sky or features on them, just as geographers have no purview to control people’s naming of features along hiking trails. People clearly enjoy connecting to the sky and having an input to common-use naming. We will continue to stand up for the public’s rights in this regard, and look forward to raising more grant funds for space researchers and educators this way.

The company also pointed out that even astronomers name things without the IAU’s approval.

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The International Astronomical Union has issued a press release condemning the commercial efforts of private companies to issue names for exoplanets.

Turf war! The International Astronomical Union has issued a press release condemning the commercial efforts of private companies to issue names for exoplanets.

Recently, an organisation has invited the public to purchase both nomination proposals for exoplanets, and rights to vote for the suggested names. In return, the purchaser receives a certificate commemorating the validity and credibility of the nomination. Such certificates are misleading, as these campaigns have no bearing on the official naming process — they will not lead to an officially-recognised exoplanet name, despite the price paid or the number of votes accrued.
… [snip]
To make this possible, the IAU acts as a single arbiter of the naming process, and is advised and supported by astronomers within different fields. As an international scientific organisation, it dissociates itself entirely from the commercial practice of selling names of planets, stars or or even “real estate” on other planets or moons. These practices will not be recognised by the IAU and their alternative naming schemes cannot be adopted.

Well la-dee-da, how dare anyone else name anything ever in space!

The truth is, the IAU was originally given this function by astronomers to coordinate the naming of obscure astronomical objects, not to provide the official names for every object and feature that will ever be discovered in space. And though the IAU does tend to favor the choices of discoverers, it has in the past also ignored their wishes. (See for example my book Genesis: the Story of Apollo 8, where the IAU rejected the names chosen by the Apollo 8 astronauts, even though those astronauts were the first to actually go and see these features.)

In the end, the names of important features in space will be chosen by those who live there.

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Despite a rest, Kepler’s problematic gyroscope is still having problems.

Despite a rest, Kepler’s problematic gyroscope is still having problems.

Three of the wheels are needed for Kepler’s 3.1-foot telescope to have enough sensitivity to detect the minuscule signatures of Earth-sized planets. In an exercise of caution, mission managers switched off Kepler’s reaction wheels for 10 days in January, hoping the break would redistribute lubricant inside the wheel assemblies, reducing friction and allowing the units to cool down.

But friction in wheel no. 4, which has showed friction for much of Kepler’s mission, actually increased in the month following the “wheel rest” period.

The telescope originally had four wheels. One has failed, with a second showing signs of failure. If it goes, the spacecraft will no longer be able to point with enough accuracy to do its primary mission. They might be able to use it to some observations, but its design is such that even these will be of limited value.

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The location of the volcanoes on Titan are not where scientists had expected them to be.

The uncertainty of science: The location of the volcanoes on Titan are not where scientists had expected them to be.

As Io moves closer to Jupiter, the planet’s powerful gravity pulls hard on the moon, deforming it. This force decreases as Io retreats, and the moon bounces back. This cycle of flexing creates friction in Io’s interior, which in turn generates enormous amounts of volcano-driving tidal heat. Common sense suggests that Io’s volcanoes would be located above the spots with the most dramatic internal heating. But Hamilton and his colleagues found that the volcanoes are significantly farther to the east than expected.

Many of the news headlines, including the article above, have trumpeted how the volcanoes on Io are in the wrong place. (See also this article.) Not. The theories were wrong, not the volcanoes. Nature does what it wants to do. It is our job to figure out why.

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