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Moon, Mars and Venus from a sea cave

View larger. | The moon, Mars and Venus from a sea cave by Jack Fusco.  Visit Jack Fusco on Facebook

Photo by Jack Fusco.

Jack Fusco captured this photo at Solana Beach in San Diego County, California on January 23. He’s working on a series of images from sea caves throughout the San Diego area.

Identify the Winter Circle and winter’s brightest stars

2015-jan-30-orion's-belt-winter-circle-winter-triangle-moon-night-sky-chart

Tonight’s chart covers a wider area of sky than we typically show. It’s in answer to a reader in Nashville, who wrote, I’ve heard mention of the Winter Circle of Stars. Could you list the stars in this circle?

Winter Circle: Winter’s brightest stars

You will find these stars at this time of year by looking southeast at early-to-mid evening, and more southward from mid-to-late evening. Although the almost-full waxing gibbous moon shines within the Winter Circle tonight, all the stars of the Winter Circle (sometimes called the Winter Hexagon) are first-magnitude stars, so they should be able to withstand tonight’s drenching moonlight. Note also that the Winter Triangle – formed by bright stars Sirius, Betelgeuse and Procyon – make up the southeast part of the Winter Circle.

Hear the birth of an iceberg

Distinctive underwater sounds announce the birth of an iceberg, say researchers. In a recent study, scientists used underwater microphones aboard buoys to record a variety of iceberg births at the Hans Glacier in Svalbard, Norway during three days in August 2013. These recordings were combined with time-lapse photos of the glacier during the same time period.

Star of the week: Betelgeuse will explode someday

Betelgeuse imaged in ultraviolet light by the Hubble Space Telescope and subsequently enhanced by NASA. The bright white spot is likely one of its poles. NASA/ESA credit.

There has been a lot of excitement this month about the supernova in the distant galaxy M82. It is the closest supernova in many years, despite the fact that it’s some 11-12 million light-years away. On a January or February evening, come to know the red star Betelgeuse in the constellation Orion. It’s not only one of Orion’s brightest stars. It’s also a star that astronomers know will one day explode as a supernova. And it’s only 430 light-years away! Follow the links inside to learn more about Betelgeuse and its explosive destiny.

Astrophysicists’ update on enormous and unexpected Fermi bubbles

From end to end, the newly discovered gamma-ray bubbles (magenta) extend 50,000 light-years, or roughly half of the Milky Way's diameter. (Credit: NASA's Goddard Space Flight Center)

The Fermi bubbles extend from our galaxy’s center. From end to end, they extend 50,000 light-years, or roughly half the Milky Way’s diameter. Illustration via NASA’s Goddard Space Flight Center

Discovered in 2010, two vast and mysterious Fermi bubbles radiate outward tens of thousands of light-years from our Milky Way galaxy’s core. Click inside for an update on the bubbles from the three astrophysicists who found them.

Huge distant planet has rings 200 times larger than Saturn’s

Artist’s conception of the extrasolar ring system circling the young giant planet or brown dwarf J1407b. The rings are shown eclipsing the young sun-like star J1407, as they would have appeared in early 2007.  Image credit: Ron Miller

Artist’s conception of the extrasolar ring system circling the young giant planet or brown dwarf J1407b. The rings are shown eclipsing the young sun-like star J1407, as they would have appeared in early 2007. Image credit: Ron Miller

Astronomers have found the first-ever ringed planet beyond our solar system. Called J1407b, the super-world has a disc of halos 200 times bigger than Saturn’s. Click inside for details on this discovery, plus … how it might look in our sky.

Behind the clouds

Dreaming the night away while waiting for the clouds to clear.

Use moon and stars to imagine Pioneer 10 on January 29

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Tonight – January 29, 2015 – cast your mind outward in space toward the Pioneer 10 spacecraft, one of the most distant spacecraft from Earth at this time. Pioneer 10 was launched from Earth on March 3, 1972. It was the most distant human-made object from Earth until Voyager 1 overtook it – at 69 Earth-sun distance units, or astronomical units – in 1998. On January 29, 2015, both the moon and Pioneer 10 reside in the direction of the constellation Taurus the Bull. You can’t see it (and it can’t see Earth), but you can imagine it tonight.

Flowing water on Vesta?

This image shows Cornelia Crater on the large asteroid Vesta. On the right is an inset image showing an example of curved gullies, indicated by the short white arrows, and a fan-shaped deposit, indicated by long white arrows. Image Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA.  View larger and read more about this photo.

This image from the Dawn spacecraft shows Cornelia, a crater on the large asteroid Vesta. The inset on the right shows an example of curved gullies, indicated by the short white arrows, and a fan-shaped deposit, indicated by long white arrows. Image via NASA/JPL-Caltech/UCLA/MPS/DLR/IDA.

Fascinating news this month about asteroid 4 Vesta – fourth asteroid to be discovered and second-most-massive asteroid after the dwarf planet 1 Ceres. NASA’s Dawn spacecraft visited Vesta from 2011 to 2013, and the new study is based on evidence from Dawn. The new study shows that – although Vesta was once assumed to be completely dry, incapable of retaining water because of the low temperatures and pressures at its surface – there’s evidence that Vesta may have had short-lived flows of water-mobilized material on its surface. Wow, yes?

View from space: India by night and by day

Acquired January 12, 2015.  Image credit: NASA

Acquired January 12, 2015. Image credit: NASA

Two astronaut photos, one from 2015 and one from 1966, show the southern peninsula of India by night and by day. See the daytime view inside.