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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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This Blazing Quasar Got Wave Motion Gunned Clear Out Of Its Galaxy

Hubble image of quasar 3C 186 racing out of from its host galaxy, 8 billion light-years away from Earth. Credit: NASA, ESA, and M. Chiaberge (STScI and JHU).

Astronomers still have yet to directly capture an image of a black hole—they’re working on it—but they know where some of the largest ones are: inside the hearts of galaxies, where they power brilliant and powerful quasars whose light can be seen across the Universe. Some of these supermassive black holes (SMBs) can contain the mass of millions if not billions of Sun-sized stars and, when two galaxies happen to collide (which they often do) their respective resident SMBs can end up locked in an orbital embrace. As their spinning dance grows tighter and tighter they send out gravitational waves, rippling the very fabric of space and time itself (the LIGO experiment announced the first detection of these waves in 2016.) But if the gravitational waves are uneven, say because the two merging SMBs are of vastly different masses and/or individually spinning in different orientations (a possible but not common scenario) then the super-duper-supermassive black hole that results from the merger can end up getting one serious cosmic-scale kick after the event occurs and the waves shut off—perhaps a strong enough kick to send it hurtling out of the galaxy altogether.

That’s what astronomers think we’re witnessing here in this image from the Hubble Space Telescope.

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This Nebula Really Stinks!

The Calabash Nebula, located 5,000 light-years away in the constellation Puppis. Image credit: ESA/Hubble & NASA

This image from the Hubble Space Telescope shows the Calabash Nebula, the cosmic death throes of a low-mass star like our Sun. Caught during the astronomically brief phase between a red giant and a planetary nebula, the star is ejecting much of its mass out into space at velocities of over 620,000 mph.

So why does it “stink?” The bright yellow jets are known to contain a lot of sulphur compounds, so if the image were a scratch ‘n’ sniff sticker it would smell like rotten eggs (hence its nickname, Rotten Egg Nebula.)

This spectacular display won’t last long; with its eruption begun in earnest about 800 years ago, in another 1,000 years this will resemble a more typical planetary nebula. In fact, given that this object is 5,000 light-years away, it’s technically already done with its sulfurous outburst! We’re just now seeing the light from the event as it arrives at Earth.

Read more in the NASA release: Hubble Captures Brilliant Star Death in “Rotten Egg” Nebula

Hubble Detects Dusty Shadows Hinting at a Hidden Exoplanet

Hubble images of a disk of gas and dust around a star 192 light-years away. The dark areas inside the disk are thought to be shadows cast by a raised portion of an inner disk, pulled upwards by an unseen exoplanet in an inclined orbit. Credit: NASA, ESA, and J. Debes. (STScI)

When searching nearby stars for exoplanets, astronomers typically either look for the dimming of the stars’ light as planets pass in front of them or try to see if the stars themselves exhibit a slight wobble due to the gravitational tug of orbiting worlds. But recently scientists using the Hubble Space Telescope have found a curious clue in the disk of gas and dust surrounding a star 192 light-years away: a long, darkened swath that orbits the star every 16 years and may indicate the presence of an orbiting planet.

“The fact that I saw the same motion over 10 billion miles from the star was pretty significant, and told me that I was seeing something that was imprinted on the outer disk rather than something that was happening directly in the disk itself,” said John Debes of the Space Telescope Science Institute (STScI) in Baltimore, Maryland, leader of the research team. “The best explanation is that the feature is a shadow moving across the surface of the disk.”

Read the full story from NASA at Hubble Captures ‘Shadow Play’ Caused by Possible Planet

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