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Science Wire | Nov 20, 2015

What makes a halo around the sun or moon?

A ring or circle of light around the sun or moon is called a halo by scientists.

Edwin Hubble 1889-1953
Blogs | This Date in Science | Nov 20, 2015

This date in science: Edwin Hubble and the expanding universe

Hubble helped change our cosmology: our idea of the universe as a whole.

View larger. | Stars wheel around Polaris, above the Hobby-Eberly Telescope at McDonald Observatory in West Texas.  Image via Ethan Tweedle Photography.
Science Wire | Nov 20, 2015

Texas telescope to explore dark energy

A mysterious and largely unknown dark energy is thought to pervade our universe. A telescope in West Texas is poised to survey a million galaxies, to explore it.

body insides
Science Wire | Nov 20, 2015

How a year in space changes bodies

Astronauts are spending a year aboard the International Space Station, and researchers are looking at what happens to their bodies at the molecular level.

Kepler-438b: The planet Kepler-438b is shown here in front of its violent parent star. It is regularly irradiated by huge flares of radiation, which could render the planet uninhabitable. Here the planet’s atmosphere is shown being stripped away. Superflares have energies roughly equal to or greater than 10^33 erg, about 10 times greater than the most powerful solar flare on record. They have been observed with energies up to around 10^36 erg -- some 10,000 times the size of biggest solar flare.  Image credit: Mark A Garlick / University of Warwick
Science Wire | Nov 18, 2015

Most Earthlike exoplanet is uninhabitable

Kepler-438b – 470 light years from Earth – ranks highest on the Earth Similarity Index. But radiation from its violent parent star makes it uninhabitable.

This map shows the route driven by NASA's Curiosity Mars rover from the location where it landed in August 2012 to its location in mid-November 2015, approaching examples of dunes in the "Bagnold Dunes" dune field. Image Credit: NASA/JPL-Caltech/Univ. of Arizona
Science Wire | Nov 17, 2015

Mars rover heads for active dunes

No Mars rover has yet visited a sand dune, as opposed to smaller sand ripples or drifts. Curiosity will visit actual Mars dunes in the next few days.

Regulus, the brightest star in the constellation Leo the Lion, dots a backwards question mark of stars known as the Sickle. If you trace all the Leonid meteors backward, they appear to radiate from this area of the sky. This year, in 2015, the planet Jupiter shines in eastern Leo, not far from the Lion's Tail.
Tonight | Nov 17, 2015

Everything you need to know: Leonid meteor shower

Here are all the details you need for 2015’s Leonid meteor shower, peaking on the morning of November 18.

The supergiant elliptical galaxy M87, with its jet. Astronomers have measured distinct pulsations from this galaxy - the combined light of the pulsating stars within it.
Science Wire | Nov 16, 2015

Astronomers take a galaxy’s pulse

Astronomers had not considered the effect of variable stars on the light of distant galaxies. A new technique lets them measure the galaxies’ “heartbeats.”

Photo by Justin Ng
Tonight | Nov 16, 2015

EarthSky’s meteor shower guide for 2015

The famous Leonid shower is coming up. Follow the links in this post to learn more about meteor showers for the rest of 2015.

Part of the Arecibo radio message beamed to space on November 16, 1974.
This Date in Science | Nov 16, 2015

This date in science: First intentional radio message to space

Anniversary of the first radio message intentionally beamed outward. What do you think? Should we be advertising our presence in space?