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Mercury and Venus close before sunrise

2016-february-11-venus-mercury

Technically speaking, Mercury and Venus will not have a conjunction this month. However, these two worlds will be staging a quasi-conjunction over the next several mornings. A quasi-conjunction is said to take place whenever two planets come to within 5o of each other on the sky’s dome, yet do not align north and south of one another.

Lightning strikes, seen from ISS

Is this cool or what? Time-lapse video from International Space Station astronaut Tim Peake.

Earthlike exoplanets with Earthlike interiors?

This artist's illustration compares the interior structures of Earth (left) with the exoplanet Kepler-93b (right), which is one and a half times the size of Earth and 4 times as massive. New research suggests that rocky worlds share similar structures, with a core containing about a third of the planet's mass, surrounded by a mantle and topped by a thin crust. Image credit: M. Weiss/CfA

This artist’s illustration compares the interior structures of Earth (left) with the exoplanet Kepler-93b (right), which is one and a half times the size of Earth and 4 times as massive. New research suggests that rocky worlds share similar structures, with a core containing about a third of the planet’s mass, surrounded by a mantle and topped by a thin crust. Image credit: M. Weiss/CfA

Rocky planets orbiting other stars have interiors similar to Earth’s, with a thin outer crust, thick mantle, and Mars-sized core, says a new study.

How to watch Thursday’s big reveal about gravitational waves

Gravitational waves are created in some of the most violent events in our universe, such as the merger of two black holes.  one.Image via Swinburne Astronomy Productions / NASA JPL.

Gravitational waves are created in some of the most violent events in our universe, such as the merger of two black holes. one.Image via Swinburne Astronomy Productions / NASA JPL.

The science world is buzzing with rumors about the pending announcement by LIGO – the leading ground-based observatory for the detection of gravitational waves – coming up on Thursday, February 11, 2016. Virtually everyone believes LIGO will announce it has found and confirmed gravitational waves at last, and, if so, few doubt that the discovery will be worth a Nobel Prize.

Star of the week: Sirius is Dog Star and brightest star

The star Sirius and the

The star Sirius and the nearby star cluster M41 caught on January 2, 2016 in Weatherly, Pennsylvania. Photo by Tom Wildoner at LeisurelyScientist.com.

February evenings are a grand time to see the star Sirius in the constellation Canis Major. It’s also fun to spot Sirius as it ascends in the east before dawn on August mornings. Whenever you see Sirius, you’ll recognize it easily because it is our sky’s brightest star.

Merging galaxies in Eridanus, via Hubble

Merging galaxies in Eridanus.

Merging galaxies in Eridanus, as captured by the Hubble Space Telescope. Image via ESA/Hubble & NASA/Judy Schmidt.

Characterized as a peculiar galaxy, NGC 1487 is an elaborate cosmic whirl likely formed when several dwarf galaxies merged.

Volcanos, lakebeds and possible Mars life

The floor of a basin on Mars where Rodriguez and others propose in this investigation that shallow lakes could have formed. These lakes could have provided an abode for life, these scientists say.

The floor of a basin on Mars where Rodriguez and others propose in this investigation that shallow lakes could have formed. These lakes could have provided an abode for life, these scientists say. Image via PSI.

Scientists are traveling to Tibet this summer to explore places that might be possible earthly analogs to regions on Mars once suitable for life.

Orion and the Chinese New Year

The three Belt stars of Orion on February 7, 2016 via Jeff Dai and Jingyi Zhang.  Visit Jeff Dai on Facebook.

The three Belt stars of Orion on February 7, 2016 via Jeff Dai and Jingyi Zhang.

A photo from China of the three Belt stars of Orion the Hunter and a short discussion of these stars in Chinese tradition … just in time for the Chinese New Year celebration going on this week across Asia.

Blue-white Rigel is at the foot of Orion

Rigel is one of Orion's two brightest stars.  The two are located on either side of a short, straight row of three medium-bright stars - Orion's Belt.

Rigel is one of Orion’s two brightest stars. The two are located on either side of a short, straight row of three medium-bright stars – Orion’s Belt.

Look for the bright star Rigel below Orion’s Belt stars. If this star were as close as our sun, it would outshine the sun by 40,000 times!

Icy volcano in Chile about to erupt?

New crater near the summit at Chillán. Image credit: SERNAGEOMIN

New crater near the summit at Chillán. Image credit: SERNAGEOMIN

Several recent events suggest that a set of glacier-covered volcanoes in the southern Chilean region of Bío-Bío may be likely to erupt.