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Glossary

 

CME
Large amounts of plasma (consisting of mostly electrons and protons) ejected from the sun.
Gamma-Ray Bursts
Short bursts of gamma-rays (very high frequency electromagentic radiation) with very energetic explosions. These bursts can last from a few milliseconds to a few about an hour.
Geomagnetic Storms
A disturbance in the Earth's magnetosphere caused by changes in space weather such as solar erutptions.
Heliosphere
The region around the sun that is filled with the Sun's gases, solar winds, and magentic fields.
IMF
The magnetic field produced by the Sun that is carried through by solar winds.
Ionosphere
The uppermost part of the atmosphere. It also forms the inner surface of the magnetosphere and is reponsible for radio communication between distant places on Earth.
Lagrangian Point
Equilibrium points in space where the gravitational pull by a massive body is equal to that of another body.
Magnetosphere
Forms when a stream of charged particles, such as a solar wind, interacts with the magnetic field of a planet.
Photosphere
The surface of the sun that you see.
Solar Eruptions
These are sudden intense bursts of energy in the sun. They may develop in a few minutes and last for several hours.
Solar Wind
A constant stream pf charged particles, such as electrons and protons, that are continuously ejected from the upper atmosphere of the Sun.
Suprathermal Ions
Ions, charged particles, that have more energy than similar particles of the same type.

Can’t find the word here? Check out our full glossary

Archive 2001

Nov 6, 2001

A fast-moving Coronal Mass Ejection that billowed away from the Sun on Nov. 4th swept past our planet on Nov 6th on Nov 5th and triggered widespread auroras. Observers as far south as central California have reported vivid Northern Lights.

Oct 26, 2001

A powerful solar explosion on Thursday, Oct 25th, sent a Coronal Mass Ejection (CME) billowing toward Earth. The expanding cloud could trigger auroras when it reaches our planet on Oct 27th or 28th. If so, the coming weekend would be the second in a row that high-latitude sky watchers have enjoyed Northern Lights.

Oct 21, 2001

An interplanetary shock wave, spawned by a solar explosion last Friday, swept past Earth on October 21st at approximately 1645 UT. The solar wind shock wave that buffeted Earth's magnetosphere today could be just the first of two heading for our planet. If so, the ongoing storm could intensify when the second arrives later today (21 Oct.) or tomorrow (22 Oct).

Oct 19, 2001

Twisted magnetic fields above sunspot 9661 erupted this morning, unleashing an X-class solar flare and hurling a Coronal Mass Ejection toward Earth. The expanding cloud will likely strike our planet's magnetosphere on October 21st during the peak of the Orionid meteor shower. Sky watchers, especially those living at higher latitudes, could spot both meteors and auroras this weekend.

Oct 11, 2001

A solar wind shock wave, spawned by a Coronal Mass Ejection (CME) that left the Sun on October 9th, swept past Earth today between 1630 and 1700 UT (12:30 and 1:00 pm EDT). Sky watchers, especially those living above geomagnetic latitude 50 degrees, should watch for Northern Lights after sunset. (The best time to spot auroras is usually around local midnight.) The interplanetary magnetic field (IMF) near Earth turned sharply south as the CME disturbance passed our planet. South-pointing IMFs often intensify geomagnetic activity, which makes this event a promising one to watch. Visit spaceweather.com for details and updates. (spaceweather.com)

Oct 1, 2001

A solar proton storm is underway following an M9-class eruption on the Sun today. The blast also hurled a bright lopsided Coronal Mass Ejection into space and, perhaps, a solar wind disturbance toward Earth. (spaceweather.com)

Oct 1, 2001

A pair of solar wind disturbances buffeted Earth's magnetosphere during the weekend and triggered a geomagnetic storm. On Sunday, Sept. 30th, and Monday, Oct. 1st, high-latitude sky watchers spotted some of the most beautiful Northern Lights of the young aurora season. Forecasters say there is also a chance for more auroras during the nights ahead. The best time to look is around local midnight. (spaceweather.com)

Sept 25, 2001

An interplanetary shock wave spawned by Monday's powerful solar explosion swept past our planet at approximately 2100 UT (2:00 p.m.DT) on Tuesday, Sept. 25th. The solar wind velocity soared from 400 km/so more than 800 km/s in a matter of minutes as the shock wave sped by.Earth is still inside the resulting high-speed solar stream and aurorasare possible tonight even at low latitudes where such displays rarelyhappen. Sky watchers are advised to look for Northern Lights after localsunset. Local midnight is usually the best time for aurora spotting but ifa powerful geomagnetic storm develops bright auroras might be visible atany time of the night. (spaceweather.com)

Aug 27, 2001

An interplanetary shock wave triggered by a powerful solar explosion two days ago buffeted Earth's magnetosphere between 19:30 and 20:00 UT on Monday, August 27th. The impact will likely trigger auroras at high-latitudes. Far-northern sky watchers across Europe and North America should be alert for Northern Lights after nightfall, especially around local midnight. (spaceweather.com)

Aug 10, 2001

A Coronal Mass Ejection that billowed away from the Sun on Thursday could deliver a glancing blow to Earth's magnetosphere this weekend. There is a fair chance that high-latitude sky-watchers could spot Northern Lights around local midnight on Saturday, August 11th, or Sunday August 12th.

June 21, 2001

STEREO Team's Eclipse 2001 Participations: For scientists, eclipses are more than just breathtaking—they’re an opportunity to see things that can’t ordinarily be seen, subtle details that are usually drowned out by the Sun’s brilliant light. One key feature of the Sun that becomes especially clear during a solar eclipse is the Sun’s atmosphere, or corona. If you’re fortunate enough to witness a solar eclipse, you’ll see the corona as a blazing halo around the Sun. Click here for more.

April 13, 2001

An interplanetary shock wave struck Earth's magnetosphere early on Friday the 13th and triggered a strong geomagnetic storm. Forecasters anticipate that a second shock wave will arrive later Friday or Saturday, possibly intensifying the ongoing disturbance. Middle-lattitude sky watchers should remain alert for auroras after local sunset. (spaceweather.com)

April 11, 2001

A pair of Coronal Mass Ejections that hit Earth's magnetosphere on April 11th sparked an intense display of auroras. Sky watchers in the United States saw "Northern Lights" as far south as the New Mexico-Texas border. (spaceweather.com)

April 2, 2001

Sunpot 9393, the largest sunspot in ten years, unleashed a pair of X1-class solar flares Monday morning. The explosions, near the Sun's northwest limb, hurled a Coronal Mass Ejection (CME) into space - but apparently not toward Earth. Another CME left the Sun on Sunday, April 1st following an M5-class eruption. This follows a hectic weekend in sky as these Sun storms lit up the Earth's aurora. (spaceweather.com)

March 21, 2001

A relatively dense and strongly magnetized interplanetary shock wave hit Earth's magnetosphere at ~0100 GMT on March 31st (8 p.m. EST on March 30th). Strong geomagnetic activity, including mid-latitude auroras, are likely to follow.

March 29, 2001

The largest sunspot in ten years is crossing the solar disk. The fast-growing spot, called AR9393, covers an area of the Sun equivalent to the total surface are of 13 Earths!

March 27, 2001

Fast-moving solar eruptions that overtake and devour their slower-moving kin can trigger long-lasting geomagnetic storms -- and dazzling auroras -- when they strike the Earth's magnetosphere. (Science@NASA)

March 21, 2001

A moderate geomagnetic storm that began Monday when a solar Coronal Mass Ejection buffeted Earth's magnetic field shows no immediate signs of abating. High-latitude sky watchers should be alert for auroras after local nightfall.

Feb 11, 2001

A beautiful Coronal Mass Ejection billowed away from the Sun early Sunday. Although the bulk of the explosion was directed away from the Earth, it appears that some ejecta is nevertheless heading our way. The edge of the expanding cloud will likely reach Earth on Tuesday and could trigger aurora at high latitudes. (spaceweather.com)

Jan 13, 2001

As expected, the leading edge of a Coronal Mass Ejection that billowed away from the Sun on January 10th reached our planet today. Although conditions seemed favorable for auroras, the passing shock wave did not trigger substantial geomagnetic activity. (spaceweather.com)

Last updated 01/25/2010 © UC Regents