12/22/00 Watching the Angry Sun
Solar Physicists are enjoying their best-ever look at a Solar Maximum thanks to NOAA and NASA satellites. "This is a unique solar maximum in history," said Dr. George Withbroe, Science Director for NASA'sSun-Earth Connection Program. "The images and data are beyond the wildest expectations of the astronomers of a generation ago." Complete story at Science@NASA
11/24/00 Solar Flares Trigger Ongoing Radiation Storm Around Earth
This morning, two powerful solar flares triggered an ongoing radiation storm around Earth. The eruptions from a sunspot group near the center of the Sun's visible disk also launched two coronal mass ejections toward our planet. Sky watchers should be alert for aurora when CMEs strike Earth's magnetosphere later this weekend.
11/22/00 Solar Flare Stuns Stardust
One of the most intense solar radiation storms in decades temporarily blinded NASA's Stardust spacecraft, which is heading for a rendez-vous with Comet Wild-2. Science@NASA
10/6/00 Fountains of Fire Illuminate Solar Mystery, Overturn 30 Year Old Theory
Observations made by NASA's Transition Region and Coronal Explorer (TRACE) spacecraft reveal that an unidentified heat source low in the solar corona is responsible for heating coronal loops. These observations disprove previous theories about these eruptive events which hypothesized that the loops were heated evenly throughout their height. NASA Press Release
10/2/00 Largest Sunspot in 9 Years
The largest sunspot in 9 years, AR9169, appeared in mid-september, but nothing happened for two weeks as it glided quietly across the face of the Sun. Finally, just as it was disappearing from view over the Sun's western limb it unleahsed a powerful X1-class solar flare, followed by an M5-class eruption just eight hours later. Neither of the limb- directed explosions send material toward our planet.
9/12/00 Solar Storm
On Tuesday, Sept. 12, less than 24 hours after the sunspot number plunged to its lowest value of the year, the Sun unleashed a surprising full-halo coronal mass ejection (CME). The leading edge of the CME could reach EEarth on Thursday, Sept. 14. Forecasters estimate a 30% chance of severe geomagnetic disturbances (possibly including aurora) at middle latitudes when the shock front arrives. SpaceWeather.com (http://www.spaceweather.com)
9/12/00 Where did all the sunspots go?
Telescopes monitoring the Sun recorded something extraordinary yesterday - the solar disk was nearly devoid of spots. With solar maximum in full swing, the Boulder sunspot number dropped to its lowest value of the year. In spite of the "blank Sun," our planet could be in for a bit of space weather on Tuesday if, as expected, a coronal solar mass ejection that left the Sun on Saturday strikes a glancing blow to Earth's magnetosphere. The impact could trigger modest geomagnetic activity. SpaceWeather.com (http://www.spaceweather.com)
7/14/00 Powerful Solar Flare Triggers Radiation Storm
This morning an X5-class solar flare, one of the most powerful flares of the current solar cycle, triggered a proton storm in the neighborhood of our planet. Just after the eruption, coronagraphs on board the ESA/NASA Solar and Heliospheric Observatory recorded a full halo mass ejection heading toward Earth at greater than 1000 km/s (gif animation - the many speckles on the coronagraph image are caused by energetic particles from the flare striking the camera's CCD detector). SpaceWeather.com
7/11/00 Coronal Mass Ejection
Coronagraphs on board the Solar and Heliospheric Observatory recorded a fast-moving full halo coronal mass ejection on July 11th. Solar wind disturbances from that explosion and others could arrive at our planet within 48 to 72 hours. Forecasters estimate a 40% chance of major geogmagnetic activity on July 14, 2000. Also, the large sunspot group 9077 has developed a complex magnetic field configuratio that could harbor energy for major solar flares. NOAA satellites recorded a powerful X1-flare from the active region on the July 11th. More such flares are likely. SpaceWeather.com (http://www.spaceweather.com)
7/1/00 Solar Flares and Mars
The planet Mars passed 0.8 degrees from the Sun on July 1st. The close encounter was invisible to naked-eye observers on Earth because of the Sun's blinding glare. Fortunately, coronagraphs on the ESA/NASA Solar Heliospheric Observatory (SOHO) were able to record the event in a 1.6 megabyte movie that also includes three coronal mass ejections. IN the animation, the coronagraph's occulting disk is denoted by a brick-colored filled circle near the middle of the image. The white circle shows the true size of the Sun. The faint starlike object passing just above the occulting disk is the planet Mars. Although Mars appears close to the Sun in the sky, its was 239 million km from the Sun and 391 million km from Earth when these images were recorded. SpaceWeather.com (http://www.spaceweather.com/images/02jul00/marspassingby_c2_big.gif)
6/10/00 M5-Class Solar Flare
The prolific flare-producing sunspot group 9026 unleashed an M5-class solar flare along with a full halo coronal mass ejection. Material from the CME is expected to arrived near our planet around midday on June 13. SpaceWeather.com (http://www.spaceweather.com/images/10jun00/flare_195_big.gif)
5/30/00 Solar S'Mores
As a result of the solar maximum, Earth's atmosphere is "puffed up" like a marshmallow over a campfire, leading to extra drag on Earth-orbiting satellites. SpaceScience.com (http://www.spacesciences.com/headlines/y2000/ast30may_1m.htm)
5/9/00 Solar Ups and Downs
It was a rare sight so near to the Solar Maximum, but the Sun was nearly featureless on May 7, 2000. SpaceScience.com (http://www.spacesciences.com/headlines/y2000/ast30may_1m.htm)
3/2/00 Solar Flare Alert!
Last week, NASA's Polar satellite spotted a geomagnetic storm triggered by a gust of solar wind. NASA Space Science News (http://spacescience.com/headlines/y2000/ast02mar_1m.htm)
2/29/00 A Twisted Tale of Sunspots
Two large sunspots near the Sun's central meridian have developed complex magnetic fields. If solar flares erupt from these regions Earth could be in for stormy space weather. NASA Space Science News (http://spacescience.com/headlines/y2000/ast29feb_1.htm)
2/18/00 Here Comes the Sun
A "full halo" coronal mass ejection left the Sun yesterday, apparently headed directly for Earth. When the leading edge of the disturbance reaches our planet on Feb. 19 or 20, it could trigger aurora and other geomagnetic activity. Space Science News (http://spacescience.com/headlines/y2000/ast18feb_1.htm)
2/3/00 Solar Smoke Rings
The Sun put on a dynamic show this week with a series of swirling coronal mass ejections. Space Science News (http://science.nasa.gov/newhome/headlines/y2000/ast03feb_1.htm)
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