AURORA ALERTS: Did you miss the Northern Lights? Next time get a wake-up call from Space Weather PHONE
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FARSIDE BLAST: Old sunspot 1109 on the farside of the sun erupted during the late hours of Oct 8th, producing a CME and a solar tsunami. NASA's STEREO-A spacecraft recorded this movie of the blast. Earth will not be affected by these events.
NORTHERN LIGHTS FROM SPACE: A thin band of aurora borealis is running around the Arctic Circle. Click here to see it. Low-light cameras onboard the US military's DMSP F18 weather satellite photographed the display on Oct. 8th, and Paul McCrone of the Fleet Numerical Meteorology and Oceanography Center in Monteray, California, processed the data for spaceweather.com. This is not a major event, but it is a photogenic one from 450 miles overhead.
SDO SEES MOUNTAINS ON THE MOON: On Oct. 7th, NASA's Solar Dynamics Observatory observed its first lunar transit when the new Moon passed directly between the spacecraft and the sun. SDO's 16 megapixel cameras recorded the event in detail, revealing jagged lunar mountains backlit by solar plasma:
Beyond the novely of observing a such an event from space, these images have practical value to the SDO science team. Karel Schrijver of Lockheed-Martin's Solar and Astrophysics Lab explains: "The very sharp edge of the lunar limb allows us to measure the in-orbit characteristics of the telescope--e.g., light diffraction on optics and filter support grids. We can use that information to correct our data for instrumental effects and sharpen up the images to even more detail."
Ralph Seguin, also of Lockheed-Martin, has prepared a movie of the transit which shows the Moon interrupting an eruption on the sun's northwestern horizon. Watch it again. Did you notice the brief blackout near the beginning of the movie? That was the Earth passing in front of the sun just before the Moon did--a double solar eclipse!
COMET HARTLEY AND THE DOUBLE CLUSTER: Comet 103P/Hartley 2 continues to put on a good show as it approaches Earth for an 11-million-mile close encounter on Oct. 20th. Last night it passed by the Double Cluster in Perseus. The contrast between the blue stars of the two clusters and the green atmosphere of the comet was remarkable:
Image credit: Michael Jäger of Stixendorf, Austria. [details]
Most observers agree that the comet is not yet visible to the naked eye, but it is an easy target for backyard telescopes. In recent nights, astronomers have enjoyed watching Comet Hartley 2 pass a succession of stars and deep-sky objects such as the Pacman nebula and the Double Cluster. Next up is eta Persei (η Per), a 4th-magnitude star that will shine through the comet's atmosphere on Oct 9th and 10th. Details and a sky map are available from from Sky & Telescope.
more images: from Mike Broussard of Maurice, Louisiana; from David A Harvey of Tucson, Arizona; from Tamás Ábrahám of Zsámbék, Hungary; from Nick Howes using the 2 Metre Faulkes North Telescope in Hawaii; from Dr Paolo Candy of Ci.A.O. Cimini Astronomical Observatory - Italy; from Parks Squyres of SaddleBrooke, Arizona; from Gregg Ruppel of Ellisville, MO; from Geir Øye of Ørsta, Norway; from Mohammad Rahimi of Honjan - Esfahan - Iran; from Joe Wheelock of McDonald Observatory, Texas; from Alex Roca of Hortoneda Lleida Spain; from Fredrik Broms of Kvaløya, Norway; from Ehsan Rostamizadeh of Kerman, Iran; from Stefano Moretti of Ravenna, Italy; from Florin Marc of Tg.Mures, Romania;
Sept. 2010 Northern Lights Gallery
[previous Septembers: 2009, 2008, 2007, 2006, 2005, 2004, 2002, 2001, 2000]
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 October 9, 2010 there were 1149 potentially hazardous asteroids. 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.
| ||The official U.S. government space weather bureau |
| ||The first place to look for information about sundogs, pillars, rainbows and related phenomena. |
| ||Researchers call it a "Hubble for the sun." SDO is the most advanced solar observatory ever. |
| ||3D views of the sun from NASA's Solar and Terrestrial Relations Observatory |
| ||Realtime and archival images of the Sun from SOHO. |
| ||from the NOAA Space Environment Center |
| ||the underlying science of space weather |