Listen to radar echoes from satellites and meteors, live on listener-supported Space Weather Radio. | | |
VERY QUIET SUN: All of the sunspots on the Earthside of the sun are quiet. NOAA forecasters put the odds of a significant eruption today at no more than 1%. Solar flare alerts: text, voice.
DAYLIGHT ALIGNMENT OF PLANETS: Venus, Mars and Uranus are gathering for a remarkable alignment. But don't bother looking for the conjunction; it is happening in the daylight sky within a few degrees of the glaring sun. Using an opaque disk to block the glare, coronagraphs onboard the Solar and Heliospheric Observatory (SOHO) are able to track the planets:
Venus and Uranus will cross paths within 1.5 degrees of the sun on March 27-28. Mars and Venus have their own very close encounter on April 6-7. Mars will be so close to the sun throughout the month of April that it will limit NASA's contact with the Mars rovers and orbiters.
According to a NASA press release, "Mars will be passing almost directly behind the sun [as seen from Earth]. The sun can easily disrupt radio transmissions between the two planets during the near-alignment. To prevent an impaired command from reaching an orbiter or rover, mission controllers at NASA's Jet Propulsion Laboratory, Pasadena, Calif., are preparing to suspend sending any commands to spacecraft at Mars for weeks in April. Transmissions from Mars to Earth will also be reduced." Mars will be at its closest to the sun, a slim 0.4 degrees on April 17th.
The ongoing dance of the sun and planets is invisible to the human eye, but coronagraphs can see the show. Join SOHO for a ringside seat.
Realtime Space Weather Photo Gallery
SPACE STATION TRANSIT: With no sunspots actively flaring, the face of the sun is still and quiet--except for the spaceship. The International Space Station (ISS) broke the monotony yesterday when it zipped across the solar disk:
Russell Vallelunga photographed the transit from Cave Creek, Arizona. Travelling around Earth faster than 17,000 mph, the ISS zipped across the sun in a fraction of a second. "It took my reflexes half the transit to trigger the shutter, but I caught this image and two others after it," says Vallelunga. "It's my first attempt, and I'm glad it was sucessful!"
Space station transits of the sun happen often, but they are rarely seen (1) because of the glare and (2) because they happen so fast. A solar filter takes care of the first probem, while precise transit predictions solve the second. With NOAA predicting a 1% chance of flares, ISS transits may be the only action on the sun today. Check Calsky to find out when to trigger the shutter.
Realtime Space Weather Photo Gallery
TIPS FOR OBSERVING COMET PAN-STARRS: Comet Pan-STARRS is fading as it recedes from the sun. In recent nights, several experienced observers put its magnitude near +2.3, only about half as bright as last week. Time is running out for easy spotting and photography.
Below, astrophotographer John Chumack of Dayton, Ohio, offers "some tips for capturing your keepsake photo." Follow his recipe to take a picture like this:
"Find a low west-northwest horizon," he advises. "Be ready before sunset, so you can mark the horizon where the sun set as a reference to find the comet. A digital camera with manual settings is all you need to photograph Pan-STARRS. Try 1 to 30 second exposures at ISO settings ranging from 400 to 1600, about 30 to 45 minutes after sunset. The twilight fades fast, so increase your ISO and exposure time to compensate." Click here for additional details.
Using procedures similar to Chumack's, photographers have recently captured Comet Pan-STARRS over the Grand Canyon, Stonehenge, Greek monuments, Lake Superior, and many other scenic locations.
More: NASA video, 3D orbit, ephemeris, light curves.
Realtime Comet Photo Gallery
Realtime Aurora Photo Gallery
Realtime Noctilucent Cloud Photo Gallery
[previous years: 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2011]