Hang the Transit of Venus on your wall! Hubble-quality images from NASA's Solar Dynamics Observatory are now available as metallic posters in the Space Weather Store. | | |
MARTIAN TRIANGLE: On the same night Curiosity lands on Mars, a "Martian Triangle" will appear in sunset skies of Earth. The first-magnitude apparition on August 5th gives space fans something to do while they wait for news from the Red Planet. [video] [story]
INCOMING CME, WEAK IMPACT EXPECTED: A coronal mass ejection (CME) produced by Saturday's M6-class flare is heading toward Earth. According to analysts at the Goddard Space Weather Lab, the cloud could deliver a glancing blow to our planet's magnetic field on July 31st around 1500 UT (+/- 7 hours). Click to view the animated forecast track:
This is a slow-moving CME. The cloud's low speed (382 km/s estimated) combined with its glancing trajectory suggests a weak impact is in the offing. Nevertheless, polar geomagnetic storms are possible when the cloud arrives. Aurora alerts: text, voice.
The CME will also hit Mercury, probably with greater force. Mercury's planetary magnetic field is only ~10% as strong as Earth's, so Mercury is not well protected from CMEs. When the clouds hit, they can actually scour atoms off Mercury's surface, adding material to Mercury's super-thin atmosphere and comet-like tail.
Realtime Space Weather Photo Gallery
FOGGY SUNSPOTS: Living in a fog can have its advantages. For one thing, it allows you to see big sunspots. Mila Zinkova of San Francisco, California, sends this picture of the foggy sunset on July 28th:
The tree limbs point across the solar disk to sunspot group AR1532, the source of at least one M-class solar flare per day since July 27th. NOAA forecasters estimate a 25% chance of additional M-flares during the next 24 hours, although the actual odds seem higher. More flares (and more spotted sunsets) are in the offing. Solar flare alerts: text, voice.
Realtime Noctilucent Cloud Photo Gallery
[previous years: 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2011]
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 July 30, 2012 there were 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 |