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