Tag Archives: hubble

Steamy windows for possible settlers

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This looks like a mighty cool – hot – planet. A waterworld under an atmosphere of water vapor. There could be boiling some life over there! It’s clear (yet damp) that there’s a whole lot more to (exo)planets than the casual rock- and gas planets we have in our neighborhood:

Observations by the NASA/ESA Hubble Space Telescope have come up with a new class of planet, a waterworld enshrouded by a thick, steamy atmosphere. It’s smaller than Uranus but larger than Earth.

An international team of astronomers led by Zachory Berta of the Harvard-Smithsonian Center for Astrophysics (CfA) made the observations of the planet GJ 1214b.

“GJ 1214b is like no planet we know of,” Berta said. “A huge fraction of its mass is made up of water.”

The ground-based MEarth Project, led by CfA’s David Charbonneau, discovered GJ 1214b in 2009. This super-Earth is about 2.7 times Earth’s diameter and weighs almost seven times as much. It orbits a red-dwarf star every 38 hours at a distance of 2 million kilometers, giving it an estimated temperature of 230 degrees Celsius.

In 2010, CfA scientist Jacob Bean and colleagues reported that they had measured the atmosphere of GJ 1214b, finding it likely that it was composed mainly of water. However, their observations could also be explained by the presence of a planet-enshrouding haze in GJ 1214b’s atmosphere. … (Hubble)

Ice fiesta on Vesta?

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Though generally thought to be quite dry, roughly half of the giant asteroid Vesta is expected to be so cold and to receive so little sunlight that water ice could have survived there for billions of years, according to the first published models of Vesta’s average global temperatures and illumination by the sun.

“Near the north and south poles, the conditions appear to be favorable for water ice to exist beneath the surface,” says Timothy Stubbs of NASA’s Goddard Space Flight Center in Greenbelt, Md., and the University of Maryland, Baltimore County. Stubbs and Yongli Wang of the Goddard Planetary Heliophysics Institute at the University of Maryland published the models in the January 2012 issue of the journal Icarus. The models are based on information from telescopes including NASA’s Hubble Space Telescope. …(NASA)

Gone, gone

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Using NASA’s Hubble Space Telescope, astronomers have solved a longstanding mystery on the type of star, or so-called progenitor, that caused a supernova in a nearby galaxy. The finding yields new observational data for pinpointing one of several scenarios that could trigger such outbursts.

Based on previous observations from ground-based telescopes, astronomers knew that a kind of supernova called a Type Ia created a remnant named SNR 0509-67.5, which lies 170,000 light-years away in the Large Magellanic Cloud galaxy. The type of system that leads to this kind of supernova explosion has long been a high importance problem with various proposed solutions but no decisive answer. All these solutions involve a white dwarf star that somehow increases in mass to the highest limit. Astronomers failed to find any companion star near the center of the remnant, and this rules out all but one solution, so the only remaining possibility is that this one Type Ia supernova came from a pair of white dwarfs in close orbit. (HubbleSite)

A distant Type-Ia

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These three images taken by NASA’s Hubble Space Telescope reveal the emergence of an exploding star, called a supernova.

Nicknamed SN Primo, the exploding star belongs to a special class called Type Ia supernovae, which are distance markers used for studying dark energy and the expansion rate of the universe. Type Ia supernovae most likely arise when white dwarf stars — the burned-out cores of normal stars — siphon too much material from their companion stars and explode. … (HubbleSite)

More iPad astro apps

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Yesterday I posted a short review of the Redshift App. Of course there’s more to get. On my iPad I have the following astronomy related apps:

Planetarium apps: Redshift, Sky Safari, Star Walk,Solar Walk;

Atlas apps: Moon Globe HD, Mars Globe HD, Google Earth

Info/eBooks: NASA Visualization Explorer, ESA, Hubble Top 100, Journey to the Exoplanets.

Follow the various links for more information.

A new galactic batch at our disposal

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In the distant reaches of the universe, almost 13 billion light-years from Earth, a strange species of galaxy lay hidden. Cloaked in dust and dimmed by the intervening distance, even the Hubble Space Telescope couldn’t spy it. It took the revealing power of NASA’s Spitzer Space Telescope to uncover not one, but four remarkably red galaxies. And while astronomers can describe the members of this new “species,” they can’t explain what makes them so ruddy.

“We’ve had to go to extremes to get the models to match our observations,” said Jiasheng Huang of the Harvard-Smithsonian Center for Astrophysics (CfA). Huang is lead author on the paper announcing the find, which was published online by the Astrophysical Journal.

Spitzer succeeded where Hubble failed because Spitzer is sensitive to infrared light – light so red that it lies beyond the visible part of the spectrum. The newfound galaxies are more than 60 times brighter in the infrared than they are at the reddest colors Hubble can detect. … (Harvard-Smithsonian Center for Astrophysics)

Galactic recycling

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The secret of longevity is recycling, at least for galaxies, say astronomers who have used a trio of the world’s best telescopes to study the uncharted space around vibrant star-birthing galaxies and their not-so-vibrant siblings.

Galaxies learned to “go green” early in the history of the universe, continuously recycling immense volumes of hydrogen gas and heavy elements to build successive generations of stars stretching over billions of years. This recycling keeps galaxies from emptying their “fuel tanks” and therefore stretches out their star-forming epoch to over 10 billion years. … (Keck)