The United States, as seen from the Moon

On August 9, 2010 the camera on Lunar Reconnaissance Orbiter took some routine calibration images and captured the Earth from lunar orbit, showing the western hemisphere with relatively little cloud cover. The picture below is a tiny piece from that global image, cropped to show the United States. The details are pretty remarkable, considering the distance. You can explore the full global image in detail here.

The U.S. from the Moon

Something is recycling the methane on Mars

Research results posted today [pdf] at the European Planetary Science Congress show that the methane in Mars’s atmosphere is seasonally variable and far more short-lived than predicted, disappearing in less than a year. Some process, therefore, must be both using it and replenishing it. On Earth, that’s almost always done by some form of life process. Key quote by one of the scientists, from the press release:

“Only small amounts of methane are present in the martian atmosphere, coming from very localised sources. We’ve looked at changes in concentrations of the gas and found that there are seasonal and also annual variations. The source of the methane could be geological activity or it could be biological ­ we can’t tell at this point.”

The image below shows the three regions (in yellow) where the methane is concentrated.

Mars methane locations

Global topography of the Moon

New results from Lunar Reconnaissance Orbiter, including a new global topographic map.

Global topography of the Moon

From the caption: A lunar topographic map showing the Moon from the vantage point of the eastern limb. On the left side of the Moon seen in this view is part of the familiar part of the Moon observed from Earth (the eastern part of the nearside). In the middle left-most part of the globe is Mare Tranquillitatis (light blue) the site of the Apollo 11 landing, and above this an oval-appearing region (Mare Serenitatis; dark blue) the site of the Apollo 17 landing. Most of the dark blue areas are lunar maria, low lying regions composed of volcanic lava flows that formed after the heavily cratered lunar highlands (and are thus much less cratered).

Arctic icecap reaches 2010 minimum

It appears that the Arctic icecap has reached its 2010 minimum. Though the icecap extent in the spring was the largest since 2002 (see image below), the melt was fast and the minimum appears to be the third lowest since 1979.

Icecap extent

Does this mean the icecap is melting and will disappear shortly, as some politicians like to believe? Hardly. Though the data suggests a long term decline in ice extent, recent trends also show evidence that the icecap might be recovering. What will actually happen is still anyone’s guess.

How blind cave fish find food

How blind cave fish find food. Key quote:

“Vibration Attraction Behavior” (or VAB) is the ability of fish to swim toward the source of a water disturbance in darkness. Postdoctoral associate Masato Yoshizawa measured this behavioral response in both wild caught and laboratory raised cave and surface-dwelling fish using a vibrating rod at different frequencies as a stimulus. Most cavefish displayed VAB and would swim toward the vibrating rod and poke at it, while few surface fish did.

Scientists predict when the first Earthlike planet will be discovered

Don’t bet the bank on this: In a preprint paper posted tonight on the astro-ph website, scientists predict the discovery of the first Earthlike extrasolar planet — using statistical analysis alone! Fun quote:

Using a bootstrap analysis of currently discovered exoplanets, we predict the discovery of the first Earth-like planet to be announced in the first half of 2011, with the likeliest date being early May 2011.

The variability of stars according to Kepler

More data from Kepler! In a paper [pdf] published today on the astro-ph website, scientists outline Kepler’s census of the variability of stars. Key quote from the abstract:

We have separated the sample in 129,000 dwarfs and 17,000 giants, and further sub-divided, the luminosity classes into temperature bins corresponding approximately to the spectral classes A, F, G, K, and M. G-dwarfs are found to be the most stable with < 20% being variable. The variability fraction increases to 30% for the K dwarfs, 40% for the M and F dwarfs, and 70% for the A-dwarfs. At the precision of Kepler, > 95% of K and G giants are variable.

Amateur detection of Jupiter impact

The detection in June by two different amateur astronomers of an impact on Jupiter bodes well for asteroid/comet research. You can read the actual paper here. [pdf] Key quote from the abstract:

A systematic study of the impact rate and size of these bolides can enable an empirical determination of the flux of meteoroids in Jupiter with implications for the populations of small bodies in the outer Solar System and may allow a better quantification of the threat of impacting bodies to Earth. The serendipitous recording of this optical flash opens a new window in the observation of Jupiter with small telescopes.

As imagined by SF authors: the Celestial Spiral

This amazing Hubble image, showing a strange spiral to the left of the bright star, is not of a galaxy. Instead, it is a binary star system where the material from one star is being sucked away from it by the other, thus producing the spiral pattern.

celestial spiral

What is most fascinating about this discovery is that this kind of phenomenon has been predicted for decades, by both astronomers and science fiction writers. Consider for example this quote from Larry Niven from his short story, The Soft Weapon, where he describes what he thinks the binary star Beta Lyrae might look like:

There was smoke across the sky, a trail of red smoke wound in a tight spiral coil. At the center of the coil was the source of the fire: a double star. One member was violet-white, a flame to brand holes in a human retina, its force held in check by the polarized window. The companion was small and yellow. They seemed to burn inches apart, so close that their masses had pulled them both into flattened eggs, so close that a red belt of lesser flame looped around them to link their bulging equators togehter. The belt was hydrogen, still mating in fusion fire, pulled loose from the stellar surfaces by two gravitional wells in conflict.

The gravity did more than that. It sent a loose end of the red belt flailing away, away and out in a burning Maypole spiral that expanded and dimmed as it rose toward interstellar space, until it turned from flame-red to smoke-red, bracketing the sky and painting a spiral path of stars deep red across half the universe.

The magnetic field flips

Back to the drawing board! Though the theories say it can’t happen that fast, scientists have found evidence that 16 million years ago the Earth’s magnetic field flipped polarity in less than five years. Even more depressing for the theorists is that this is the second such fast flip researchers have discovered.

Opportunity’s journey continues

On August 18, 2010, the Mars rover Opportunity took this panorama image of the Martian terrain. Up close, patches of bedrock can be seen where the sand had blown clear. In the far distance the rim of Endeavour Crater, the rover’s long term destination, pokes up over the horizon.

Endeavour Crater on the horizon

Update: A press notice from JPL today notes that Opportunity has now traveled about half of the 11.8 mile distance to Endeavour Crater. As it took two years to go this far, the journey still has two years to go, assuming the rover survives that long.

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