SALLY RIDE (1951 - 2012): Astronaut and physicist Sally Ride died on July 23rd following a 17-month battle with cancer. Ride, who became the first American women in space in 1983 when she orbited Earth onboard space shuttle Challenger, was known for her courage, intelligence, and dedication to young scientists, especially girls. We add our condolences to those of NASA and many others over the loss of a true American original.
EVENING LIGHTS: When the sun goes down tonight, step outside and look west. The crescent Moon, Mars, Saturn, and first-magnitude star Spica have converged there in a loose but beautiful grouping of bright evening lights. It's a nice way to end the day. [sky map]
VERY FAST FARSIDE CME (UPDATED): On July 23rd, a coronal mass ejection (CME) blasted away from the sun with rare speed: 3400 km/s or 7.6 million mph. CMEs moving this fast occur only once every ~5 to 10 years. The Solar and Heliospheric Observatory recorded the cloud's rapid departure from the sun:
The source of the CME was sunspot AR1520, which sparked many bright auroras earlier this month when it was on the Earthside of the sun. Now, however, the active region is transiting the sun's farside so this blast was not geoeffective. One can only imagine the geomagnetic storms such a fast CME could produce if it were heading our way.
Update: According to a forecast track prepared by analysts at the Goddard Space Weather Lab, this CME will miss all of the solar system's inner planets.
Solar wind
speed: 501.4 km/sec
density: 2.2 protons/cm3
explanation | more data
Updated: Today at 1424 UT
X-ray Solar Flares
6-hr max: C1 1149 UT Jul24
24-hr: C1 1149 UT Jul24
explanation | more data
Updated: Today at: 1400 UT
Daily Sun: 24 Jul 12
None of these sunspots poses a threat for strong flares. Credit: SDO/HMI
Sunspot number: 60
What is the sunspot number?
Updated 24 Jul 2012
Spotless Days
Current Stretch: 0 days
2012 total: 0 days (0%)
2011 total: 2 days (<1%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)
Since 2004: 821 days
Typical Solar Min: 486 days
Updated 24 Jul 2012
The Radio Sun
10.7 cm flux: 97 sfu
explanation | more data
Updated 24 Jul 2012
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 3 quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 5.5 nT
Bz: 0.4 nT north
explanation | more data
Updated: Today at 1427 UT
Coronal Holes: 24 Jul 12
A solar wind stream flowing from this coronal hole should reach Earth on July 28-30. Credit: SDO/AIA.
