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Rosetta spacecraft glimpses its own shadow

The Rosetta spacecraft's shadow on the comet it has been orbiting since last August.

The dark spot at the bottom of the frame is the Rosetta spacecraft’s shadow on Comet 67P/Churyumov-Gerasimenko, which it has been orbiting since last August. The spacecraft was only 4 miles (6 km) from the comet when this image was acquired on February 14, 2015. Image via ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

On February 14, 2015, the Rosetta spacecraft made a close flyby of Comet 67P/Churyumov-Gerasimenko. The spacecraft not only passed closer to a comet than any spacecraft had before, but it also became part of a unique space geometry that let the spacecraft’s shadow fall on the comet’s icy surface.

The intriguing cycle of closest and farthest moons

lunar-perigee-lunar-apogee

In March 2015, the moon swings out to apogee – farthest point from Earth in its orbit – on March 5, and then reaches perigee – its nearest point – on March 19. We list the dates for this year’s 13 apogees and 13 perigees.

First photo of light as particle and wave

This image shows the dual nature of light - its property of being both a wave and a particle simultaneously - a property known for decades, but never before witnessed by human eyes.

This image shows the dual nature of light – its property of being both a wave and a particle – a property known since 1905, but never before witnessed in this way by human eyes.

Here is the first-ever photo of light as both a particle and a wave. It was Albert Einstein who suggested that light did not behave exactly a wave or a particle. Instead, light behaves as both wave and particle. Einstein’s theory became known as the wave-particle duality of light, and is now fully accepted by modern scientists. But who thought we’d ever see a photo of light as both a particle and a wave?

Moonlit night of plum blossoms, and other great moon and Jupiter photos

The little white dot near the moon here is Jupiter.  Photo by Masaaki Shibuya.

Moon and Jupiter on March 2, 2015. Photo by Masaaki Shibuya.

Beautiful photos of the March 2, 2015 moon and Jupiter. Our thanks to all of you who are posting at EarthSky Facebook and G+, and submitting directly to EarthSky.org. We’ll post more as we receive them!

Clearest pictures ever of free-falling snowflakes

This video traces the history of what most people think they know about snowflakes: that is, that a typical snowflake is a perfectly symmetrical six-pointed star. A new high-speed camera has acquired the clearest pictures ever taken of free-falling snowflakes, showing that our iconic notion of snowflakes as perfectly symmetrical isn’t correct. This camera is now being designed to help keep winter travelers safer.

Jupiter and Earth’s moon, and the beautiful dance of Jupiter’s moons

2015-march-3-jupiter-regulus-moon-night-sky-chart

If you’ve been watching these past few days, you know the waxing gibbous moon has been moving past the glorious planet Jupiter in our night sky. The feature sky chart at top shows the moon’s position relative to Jupiter and the star Regulus as seen on the evening of March 3 from North America. In the world’s Eastern Hemisphere – Africa, Europe and Asia – the moon still shines between Jupiter and Regulus on March 3, but is more offset toward Jupiter.

Missed the spacewalks? Here’s video, photos

Two NASA astronauts aboard the International Space Station (ISS) performed the last of Expedition 42’s scheduled spacewalks on Sunday – the third spacewalk in eight days.

See Earth in Mars’ night sky

View full size. Credit: NASA/JPL-Caltech/MSSS/TAMU

Credit: NASA/JPL-Caltech/MSSS/TAMU

What would Earth look like in Mars’ night sky? It would be somewhat similar to Venus in our sky, not as bright but still a bright morning or evening “star.” As seen from Mars, Earth would be an inner planet. It would always appear near the sun in the sky, either in the west after sunset or in the east before dawn. At those times when Earth passed between the sun and Mars, as it did last April, 2014, Earth would show phases like a tiny crescent moon.

Touching NASA tributes to Leonard Nimoy’s passing

What better tribute?  Terry Virts in the International Space Station gives the vulcan salute.

What better tribute? Terry Virts in the International Space Station gives the vulcan salute.

American astronaut Terry Virts (@AstroTerry) – orbiting 250 miles (400 km) above Earth on the International Space Station – paid this fitting tribute via Twitter to actor Leonard Nimoy, who died on Friday, February 27, 2015 at the age of 83. Nimoy will forever be known as Mr. Spock from the original Star Trek series and many of the subsequent movies. The late actor’s home state of Massachusetts can be seen just to the right of Virts’ Vulcan salute. Click inside for more tributes.

Moon closest to Jupiter on March 2

2015-march-2-jupiter-moon-night-sky-chart

Tonight – March 2, 2015 – look for the brilliant waxing gibbous moon to pair up with the dazzling planet Jupiter as soon as darkness falls. As the Earth spins eastward beneath the starry heavens tonight, it’ll cause the moon and Jupiter to travel upward and westward, until the brilliant twosome reaches its high point in the sky at late evening. They’ll continue to move westward, to set in the west just before dawn.