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Uranus Lights Up for Hubble

HST images of Uranus’ aurorae and rings combined with Voyager 2 images of the planet itself. (NASA)

Those white areas aren’t clouds; they’re aurorae—”northern lights”—around the poles of Uranus, captured by the Hubble Space Telescope in 2012 and 2014. (The image of Uranus itself was acquired by the Voyager 2 spacecraft in January 1986.)

“The auroras on Jupiter and Saturn are well-studied, but not much is known about the auroras of the giant ice planet Uranus. In 2011, the NASA/ESA Hubble Space Telescope became the first Earth-based telescope to snap an image of the auroras on Uranus. In 2012 and 2014 a team led by an astronomer from Paris Observatory took a second look at the auroras using the ultraviolet capabilities of the Space Telescope Imaging Spectrograph (STIS) installed on Hubble.”

Aurorae on Uranus are driven by the same process that creates them around Earth’s polar regions: charged particles from the Sun get caught in the planet’s magnetic field and are focused toward the poles, where they make ions in the upper atmosphere release energy—in these observations in ultraviolet wavelengths. Also, since Uranus orbits the Sun “tilted sideways” its polar regions are near the plane of its orbit.

Read the rest of this article from NASA here: Hubble Spots Auroras on Uranus

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Here’s Hubble’s Newest Knockout Portrait of Jupiter

Jupiter imaged by the Hubble Space Telescope on April 3, 2017. Credit: NASA, ESA, and A. Simon (GSFC)

On April 3, 2017, as Jupiter made its nearest approach to Earth in a year, NASA’s Hubble Space Telescope viewed the solar system’s largest planet in all of its up-close glory. At a distance of 415 million miles (668 million km) from Earth, Jupiter offered spectacular views of its colorful, roiling atmosphere, the legendary Great Red Spot, and its smaller companion at farther southern latitudes dubbed “Red Spot Jr.” Taken with Hubble’s Wide Field Camera 3, the image resolves details in Jupiter’s atmosphere as small as about 80 miles (129 km) across.

Read the full article on NASA’s Hubble site here, and check out a version I made with enhanced contrast and sharpness to bring out some details in Jupiter’s clouds below:

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Astronomers Find an Earth-Sized World with a Venus-sized Atmosphere

Artist’s concept of GJ 1132b. (Credit: Dana Berry)

Using ground-based telescopes, an international team of astronomers has identified an atmosphere around the exoplanet GJ 1132b. Orbiting a red dwarf star a mere 39 light-years away this world is only about half again as large and massive as Earth, making it the smallest exoplanet to be discovered thus far with an atmosphere.

Unfortunately that likely means that although GJ 1132b is Earth-sized it’s not Earth-like. In order to even be detected in the manner that it was the atmosphere must be extremely thick, making this exoplanet more similar to Venus than Earth.

“An atmosphere that we would think of as Earth-like would be completely invisible to these observations, and to all other currently existing telescopes,” said Tom Louden, a physicist at the University of Warwick in Coventry, England (who wasn’t involved in the study.)

Read the full article by George Dvorsky on Gizmodo here.

Get Ready for Cassini’s Glorious Grand Finale

The end is near. On September 15, 2017, NASA’s Cassini spacecraft will end its mission as well as its very existence with a plunge into the atmosphere of the very planet it has been orbiting since June 2004. It’s a maneuver intended to protect the pristine environments of Saturn’s icy moons, some of which harbor hidden reserves of liquid water, from potential impact contamination by an incapacitated spacecraft at some distant time in the future. But even though the reasons are noble, there’s no doubt that the final flight of Cassini and its inevitable loss will be a sad event for all those — myself very much included — who have followed along on its journey of discovery all these years. (Literally my first feature post here was a picture from Cassini.)

The video above, released today by NASA, is a poignant look both back at Cassini’s voyages and ahead at its Grand Finale, the last and most daring part of its mission at Saturn. These last few months will be bittersweet for Cassini fans, as every week will bring us closer to the end but also new and breathtaking views of Saturn…up to and including one last “family portrait” of the planet, its beautiful rings, and family of amazing moons.

Must be dusty in here, there’s something in my eye…

The end phase of the mission begins April 22. Follow along with the Grand Finale here.

These Photos Taken from the Moon Show Lots and Lots of Stars

Photo of a partially-lit Earth captured by the Far Ultraviolet Camera on Apollo 16. Note that stars are visible in the background. (NASA)

One of the favorite allegations by those who continue to be skeptical of the Apollo moon landings is that there are no stars visible in the photographs taken by the astronauts while they were “supposedly” on the Moon. Now while there’s a rather short but succinct list of why that’s the case (and feel free to review those reasons here) the truth is that there ARE stars visible in photographs taken from the Moon—photographs taken in ultraviolet light during the penultimate Apollo 16 mission in April of 1972.

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