When is the best time to see auroras? Where is the best place to go? And how do you photograph them? These questions and more are answered in a new book, Northern Lights - a Guide, by Pal Brekke & Fredrik Broms.
| || |
COMET LANDING SITE SELECTION: Europe's Rosetta probe has been at Comet 67P/Churyumov-Gerasimenko for two weeks, taking close-up pictures and making measurements of the comet's strange landscape. According to ESA, researchers now have the data they need to start picking a landing site. This weekend, mission planners will meet to consider 10 candidate locations, with the goal of narrowing the list to 5 by Monday. Stay tuned for results!
CELESTIAL TRIANGLE: The three brightest objects in the night sky, Venus, Jupiter and the Moon, converged this morning to form a bright triangle visible around the world. Kenneth Parsons sends this picture from Corpus Christi, Texas:
"I shot this at 6:10 AM on an absolutely clear morning with only a hint of breeze to mar the reflection of the Moon in the water," says Parsons.
Did you miss the show? Another "celestial triangle" is in the offing. This weekend the Moon will pass the sun en route to the evening sky. On August 31st it will join Mars and Saturn to form a new triangle in the constellation Libra. The new triangle won't be quite as luminous, because Mars and Saturn are not as bright as Venus and Jupiter, but the Moon-Mars-Saturn formation will be more compact and just as beautiful. Mark your calendar for the end of the month.
Realtime Conjunction Photo Gallery
STRATOSPHERIC SPACE WEATHER BUOY LAUNCHED: An 8-foot diameter ball of helium can be hard to handle. Just ask the students of Earth to Sky Calculus. Yesterday, one of their space weather balloons got caught in a gust of wind and almost got away:
For a good laugh, listen to the soundtrack of this launch video. Despite the troubles, the balloon did make it safely off the ground, marking the group's 58th successful launch. This particular flight was part of a year-long campaign to find out how the stratosphere responds to solar storms. The payload carrried cameras, GPS altimeters, a cryogenic thermometer, and a cosmic radiation detector more than 100,000 feet above sea level. Sensors gathered data for 2.5 hours before parachuting back to Earth. A student team is recovering the payload now. Stay tuned for updates later this weekend.
Realtime Space Weather Photo Gallery
SOLAR ACTIVITY PICKS UP: A new sunspot emerging over the sun's NE limb is bringing an uptick in solar activity. AR2149 announced itself on August 21st with an impulsive M3-class solar flare. NASA's Solar Dynamics Observatory recorded the explosion's extreme ultraviolet flash:
UV radiation from the flare partially ionized the upper layers of Earth's atmosphere. This "Sudden Ionospheric Disturbance" altered the normal propagation of VLF (very low frequency) radio transmissions over the northern hemisphere, shown here in a recording from the Polarlightcenter in Lofoten, Norway. The disturbance has since subsided.
Because AR2149 is near the sun's eastern horizon, our view of the region is foreshortened. Evaluating the structure of its magnetic field is therefore tricky. As the sunspot turns toward Earth in the days ahead, we will get a better idea of its flare-producing potential. For now, NOAA forecasters are estimating a 25% chance of M-flares in the next 24 hours. Solar flare alerts: text, voice
Realtime Aurora Photo Gallery
Realtime Comet Photo Gallery
Realtime Meteor Photo Gallery
Realtime NLC Photo Gallery
Every night, a network of NASA all-sky cameras scans the skies above the United States for meteoritic fireballs. Automated software maintained by NASA's Meteoroid Environment Office calculates their orbits, velocity, penetration depth in Earth's atmosphere and many other characteristics. Daily results are presented here on Spaceweather.com.
On Aug. 23, 2014, the network reported 19 fireballs.
(18 sporadics, 1 kappa Cygnid)
In this diagram of the inner solar system, all of the fireball orbits intersect at a single point--Earth. The orbits are color-coded by velocity, from slow (red) to fast (blue). [Larger image] [movies]
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 August 23, 2014 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 |