Secret Space Plane Flares

What's up in space

They came from outer space--and you can have one! Genuine meteorites are now on sale in the Space Weather Store. They make a unique Valentine's gift.   SECRET SPACE PLANE FLARES: The US Air Force's X-37B space plane is circling Earth and, although it is on a classified mission with an officially unpublished orbit, sky watchers have spotted it. "I saw the X-37B from my home in Pasadena, California, around sunrise on March 31st," reports Anthony Cook of the Griffith Observatory. "The spacecraft's appearance was remarkable. When overhead it was a little brighter than a 2nd magnitude star with a slight yellow hue. Then it flared. As the X-37B moved toward the horizon it became silvery and brightened to around magnitude -6, far outshining Venus below it." The flare was presumably caused by sunlight glinting from some flat surface on the shuttle-shaped spacecraft, but no one can say for sure because it is a classified mission. Ready for a secret flare of your own? Space plane flyby preditions may be found on the Simple Satellite Tracker or on your cell phone. SATURN'S RINGS SURGE IN BRIGHTNESS: This Sunday, April 3rd, Saturn will be "at opposition"--that is, opposite the sun in the skies of Earth. Whenever this happens, Saturn's rings surge in brightness. Why? Scroll down for the explanation; on the way, inspect this photo taken by Paul Haese of South Australia on March 30th: "This is how Saturn looked through my 14-inch telescope," says Haese. "With opposition so close, the Seeliger effect is really starting to show itself. The rings are much more spectacular than in previous years." The Seeliger effect, also known as the opposition effect, is what brightens the rings. Saturn's rings are made of frozen chunks ranging in size from dust to houses. Sunlight directly backscattered from those ice particles causes the ring system to shine even more than usual for a few days around opposition. The exact mechanism involves shadow-hiding and possibly coherent backscattering. To find Saturn, go outside at midnight and look for a conspicuous yellow "star" in the constellation Virgo. Even a small telescope will show Saturn's brightening rings. [sky map] more images: from Efrain Morales Rivera of Aguadilla, Puerto Rico; from Christopher Go of Cebu City, Philippines APRIL AURORAS: According to the space weather forecast, geomagnetic storms were unlikely on April 1st. It would've been foolish to go out looking for Northern Lights. Warren Gammel of Fairbanks, Alaska, decided to check the skies anyway, and this is what he saw: "I didn't expect to see too much when I went out at 2 a.m. on April 1st, but the auroras were fairly strong," he says. "I took these pictures using a Canon T1i with a Pelang 8mm fisheye lens." The display was caused by a minor but effective solar wind stream that arrived during the early hours of April 1st. The impact sparked bright lights across the Arctic realm of North America. No joke: It pays to be alert for auroras. more images: from Steve Milner near Prophet River, British Columbia, Canada   Near Earth Asteroids Potentially Hazardous Asteroids (PHAs) are space rocks larger than approximately 100m that can come closer to Earth than 0.05 AU. None of the known PHAs is on a collision course with our planet, although astronomers are finding new ones all the time. On April 2, 2011 there were 1215 potentially hazardous asteroids. Recent & Upcoming Earth-asteroid encounters: Asteroid Date(UT) Miss Distance Mag. Size 2011 FA23 Apr 1 2.1 LD -- 7 m 2011 FT9 Apr 1 7.5 LD -- 25 m 2011 FT29 Apr 6 6.2 LD -- 44 m 2002 DB4 Apr 15 62.5 LD -- 2.2 km 2008 UC202 Apr 27 8.9 LD -- 10 m 2009 UK20 May 2 8.6 LD -- 23 m 2008 FU6 May 5 75.5 LD -- 1.2 km 2003 YT1 May 5 65.3 LD -- 2.5 km 2002 JC Jun 1 57.5 LD -- 1.6 km 2009 BD Jun 2 0.9 LD -- 9 m 2002 JB9 Jun 11 71.5 LD -- 3.2 km 2001 VH75 Jun 12 42.2 LD -- 1.1 km 2004 LO2 Jun 15 9.9 LD -- 48 m 2001 QP181 Jul 2 35.1 LD -- 1.1 km 2003 YS117 Jul 14 73.9 LD -- 1.0 km Notes: LD means "Lunar Distance." 1 LD = 384,401 km, the distance between Earth and the Moon. 1 LD also equals 0.00256 AU. MAG is the visual magnitude of the asteroid on the date of closest approach.   Essential web links NOAA Space Weather Prediction Center   The official U.S. government space weather bureau Atmospheric Optics   The first place to look for information about sundogs, pillars, rainbows and related phenomena. Solar Dynamics Observatory   Researchers call it a "Hubble for the sun." SDO is the most advanced solar observatory ever. STEREO   3D views of the sun from NASA's Solar and Terrestrial Relations Observatory Solar and Heliospheric Observatory   Realtime and archival images of the Sun from SOHO. Daily Sunspot Summaries   from the NOAA Space Environment Center Heliophysics   the underlying science of space weather Conquest Graphics   for out-of-this-world printing and graphics Science Central   more links...