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Video still via of reentry of object WT1190F, via the International Astronomical Center (IAC) and the United Arab Emirates Space Agency.
Science Wire | Nov 14, 2015

Mystery object WTF has come home

It was the first time astronomers knew just when and where a piece of space debris would reenter Earth’s atmosphere. It was last night, over the Indian Ocean.

New modeling indicates that the grooves on Mars’ moon Phobos could be produced by tidal forces – the mutual gravitational pull of the planet and the moon. Initially, scientists had thought the grooves were created by the massive impact that made Stickney crater (lower right). Image via NASA/JPL-Caltech/University of Arizona
Science Wire | Nov 13, 2015

Mars’ moon Phobos slowly falling apart

The mysterious grooves on Phobos are likely early signs of structural failure. Scientists expect the moon to be pulled apart in 30 to 50 million years.

As winter sets in at Titan’s south pole, a cloud system called the south polar vortex (small, bright “button”) has been forming, as seen in this 2013 image. Image credit: NASA/JPL-Caltech/Space Science Institute
Science Wire | Nov 13, 2015

Cassini spots monstrous ice cloud on Titan

As winter sets in at the south pole of Saturn’s moon Titan, a massive ice cloud has been forming. It’s the “button” in this image from the Cassini spacecraft.

Artist's concept of the planet Mercury crossing the stream of debris left behind by Comet Encke. New research suggests that, at these crossings, Mercury undergoes a recurring meteoroid shower. Image via NASA/Goddard.
Science Wire | Nov 11, 2015

Comet Encke pelts Mercury with meteors

This comet is the same one causing the amazing display of Taurid fireballs on Earth this year. And so our solar system begins to seem a little more familiar.

Using New Horizons images of Pluto’s surface to make 3-D topographic maps, scientists discovered that two of Pluto’s mountains, informally named Wright Mons and Piccard Mons, could be ice volcanoes. The color depicts changes in elevation, blue indicating lower terrain and brown showing higher elevation. Green terrains are at intermediate heights. Image credit: NASA/JHUAPL/SwRI
Science Wire | Nov 10, 2015

Pluto might have ice volcanoes

Two of Pluto’s mountains could be cryovolcanoes – ice volcanoes – that might have spewed an ammonia-ice slurry in the recent geological past.

This composite of enhanced color images of Pluto (lower right) and Charon (upper left), was taken by NASA’s New Horizons spacecraft as it passed through the Pluto system on July 14, 2015. This image highlights the striking differences between Pluto and Charon. The color and brightness of both Pluto and Charon have been processed identically to allow direct comparison of their surface properties, and to highlight the similarity between Charon’s polar red terrain and Pluto’s equatorial red terrain. Pluto and Charon are shown with approximately correct relative sizes, but their true separation is not to scale. The image combines blue, red and infrared images taken by the spacecraft’s Ralph/Multispectral Visual Imaging Camera (MVIC). Image credit: NASA/JHUAPL/SwRI
Science Wire | Nov 10, 2015

Pluto’s moons spinning wildly

“These are four of the strangest moons in the solar system,” said New Horizons mission’s Mark Showalter. “We still don’t know what to make of it.”

Science Wire | Nov 10, 2015

How to use EarthSky’s lunar calendar

It’s beautiful. It’s the best gift ever! And it’ll help you get in touch with nature. What more could you ask? Read the 6 tips below and enjoy your moon calendar!

Image credit: NASA
Science Wire | Nov 09, 2015

NASA is recruiting astronauts

Want to be an astronaut? NASA is seeking explorers for future space missions. Here’s what it takes and how to apply.

View larger. | Image acquired by the Mars Curiosity rover on Friday 6th November 2015, via NASA / JPL / Malin Space Science Systems. Mars Science Laboratory Curiosity.
Science Wire | Nov 09, 2015

Amazing view across Mars’ Gale Crater

Another great glimpse of Mars – the world next door – from NASA’s Curiosity rover.

GRB 151027B, Swift's 1,000th burst (center), is shown in this composite X-ray, ultraviolet and optical image. X-rays were captured by Swift's X-Ray Telescope, which began observing the field 3.4 minutes after the Burst Alert Telescope detected the blast. Swift's Ultraviolet/Optical Telescope (UVOT) began observations seven seconds later and faintly detected the burst in visible light. The image includes X-rays with energies from 300 to 6,000 electron volts, primarily from the burst, and lower-energy light seen through the UVOT's visible, blue and ultraviolet filters (shown, respectively, in red, green and blue). The image has a cumulative exposure of 10.4 hours. Image via NASA/Swift/Phil Evans, Univ. of Leicester
Science Wire | Nov 09, 2015

Swift’s 1000th gamma-ray burst

This flash of gamma rays came at 6:41 p.m. EDT on October 27. Later, astronomers learned it had traveled toward Earth for 12 billion years.