USGS Astrogeology Hot Topics

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Posted by HotTopicsJournalist in Astrogeology at 15:40

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Posted by HotTopicsJournalist in Humorous at 14:42

Image: © AMY LO

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Stars shine so brightly that any planets orbiting them are lost in the glow. In fact, astronomers can only detect exoplanets indirectly by their effects on parent stars: either gravitational or, as the planet passes in front, by dimming. But a 50-meter-wide, daisy-shaped star shade could block stellar light, allowing direct observation of their planets, according to a new paper in today's Nature.

Webster Cash of the University of Colorado designed the star shade to be used in conjunction with orbiting telescopes. The thin plastic shade would cancel out a specific star's light and the telescope--trailing 15,000 miles behind--could then take in light from its distant planets. "Think of an outfielder holding up one hand to block out the sunlight as he tracks a fly ball," Cash explains. "We would use the star shade as a giant hand to suppress the light emanating from a central star by a factor of about 10 billion."

Read More: Scientific American.com -Star Shade Could Reveal Earthllike Exoplanets

Posted by HotTopicsJournalist in Odds and Ends at 14:00

Image: COURTESY OF NASA/JPL-CALTECH/R. HURT 200x175

The Fourth of July last year had some extra fireworks. NASA's Deep Impact spacecraft sent a hefty projectile--more than 800 pounds--into the body of the comet known as Tempel 1. The collision delivered 19 gigajoules of energy--the equivalent of nearly five tons of explosive TNT--into the wandering comet and ejected a plume of its innermost secrets. Roughly 10 million kilograms of comet stuff (more than 22 million pounds) spread out into space, giving scientists a rare glimpse of the ingredients that go into making a comet. Now researchers observing with the Spitzer Space Telescope have revealed their findings: comets contain a mix of materials that formed under widely divergent conditions.

Read more at SCIENCE NEWS -Deep Impact Reveals Comet's Components

Posted by HotTopicsJournalist in Other Missions at 13:35

Paris - Europe's Venus Express satellite, which entered Venus orbit in April, has cleared its commissioning phase and is ready to begin formal operations despite the fact that one of its seven observing instruments is not functioning, the European Space Agency (ESA) said July 12.

Venus Express satellite
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The Planetary Fourier Spectrometer (PFS), which encountered problems in May, is stuck in "closed" position despite weeks of efforts to return the instrument to operations, ESA said.

"[A] series of activities and further in-orbit tests [will] be conducted in the next months, as well as a series of independent investigations, to examine the origin of the problem," ESA said in a July 12 statement on Venus Express' status. "In the meantime, other instruments will cover some of the PFS objectives."

The PFS is designed to measure Venus' surface and atmospheric temperature. Part of its mission is to hunt for volcanic activity on the planet.

Venus Express was launched in November 2005 and entered Venus orbit in April, after which it began adjusting its position to arrive at the highly elliptical orbit in which it will operate. The satellite will view Venus from distances of between 66,000 kilometers and 250 kilometers.

Credit: Space.com, Peter de Selding--Despite Balky Sensor, Venus Express Ready for Operations

Posted by HotTopicsJournalist in Other Missions at 13:32