Although radio astronomy has been around since the 1930s, it is only in recent years that astronomers have been able to make high-resolution maps of the radio sky. Sky maps are difficult for radio telescopes because radio antennas need to be focused on an extremely small patch of sky to capture images in high resolution. But with modern antennas and computer processing, we can now scan the sky quickly enough to map the heavens in a reasonable amount of time.Continue reading “Australian Radio Telescopes Just Completed a map of the Universe”
Normally, SkyAlert collects and distributes reports of astronomical transients in near-real time, such as supernovae, gamma-ray bursts, cataclysmic variables and blazar eruptions. You can even get alerts of these events via Twitter or Facebook. But starting this morning, Dec 24, through Dec 25, Skyalert.org will be distributing Santa Sighting Events via Twitter and Facebook so you can track where in the universe Santa will be. SkyAlert also has some interesting images of where Santa has been — there’s evidence of Santa on the Moon; he may have been flying through the Coalsack Nebula (see below) and that even in the early Universe there may have been multiple Santas.
The Santa stream will be broadcast live on Twitter at http://twitter.com/skyalert with the tag #SantaAlert. You can also go to the SkyAlert website’s special Santa tracking page, or Facebook.
The sky is full of explosions and movement, and SkyAlert is a great way to follow all the transient events taking place. The folks at SkyAlert say the discovery rate of such transients is increasing rapidly as new surveys come online. Visit SkyAlert for more information. And enjoy the holidays!
NASA’s Wide-field Infrared Survey Explorer, or WISE, successfully lifted off this morning on its way to map the entire sky in infrared light. A Delta II rocket carrying the spacecraft launched at 6:09 a.m. PST (9:09 a.m. EST) from Vandenberg Air Force Base in California. WISE quickly began transmitting data – just 10 seconds after spacecraft separation — and all through the events that lead to bringing the satellite into a polar orbit 326 miles above Earth.
“WISE thundered overhead, lighting up the pre-dawn skies,” said William Irace, the mission’s project manager at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “All systems are looking good, and we are on our way to seeing the entire infrared sky better than ever before.”
Because the instrument sees the infrared, or heat, signatures of objects, it must be kept at chilly temperatures. Its coldest detectors are less than minus 447 degrees Fahrenheit.
“WISE needs to be colder than the objects it’s observing,” said Ned Wright of UCLA, the mission’s principal investigator. “Now we’re ready to see the infrared glow from hundreds of thousands of asteroids, and hundreds of millions of stars and galaxies.”
With the spacecraft stable, cold and communicating with mission controllers at JPL, a month-long checkout and calibration is underway.
WISE will see the infrared colors of the whole sky with sensitivity and resolution far better than the last infrared sky survey, performed 26 years ago. The space telescope will spend nine months scanning the sky once, then one-half the sky a second time. The primary mission will end when WISE’s frozen hydrogen runs out, about 10 months after launch.
WISE will catalog a variety of astronomical targets. Near-Earth asteroids, stars, planet-forming disks and distant galaxies all will be easy for the mission to see. Hundreds of millions of objects will populate the WISE atlas, providing astronomers and other space missions, such as NASA’s planned James Webb Space Telescope, with a long-lasting infrared roadmap.