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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.
The region around the sun that is filled with the Sun's gases, solar winds, and magentic fields.
The magnetic field produced by the Sun that is carried through by solar winds.
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.
Forms when a stream of charged particles, such as a solar wind, interacts with the magnetic field of a planet.
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 2003

Dec 3, 2003

California-sized cracks in our planet's magnetic field can remain open for hours, allowing the solar wind to gush through and power stormy space weather -- this according to new observations from Earth-orbiting satellites. More information is available here. (Science@NASA)

Nov 20, 2003

The solar regions that produced dramatic space weather activity in late October and early November returned to the visible side of the Sun, according to the NOAA Space Environment Center. The area known as NOAA Region 501 already produced a moderate radio blackout, R2 on the NOAA space weather scales, and spawned a sever, or G4, geomagnetic storm, which began Thursday. The full story is available here.

Nov 19, 2003

Research with the Solar and Heliospheric Observatory (SOHO) spacecraft has revealed the process that may implement the reversal in the direction of the Sun's magnetic field that is known to occur every 11 years. See the NASA Press Release for details.

Noev 14, 2003

Using a technique called helioseismic holography, astronomers can do something amazing: look through the Sun to find sunspots on the far side of our star. On Nov. 11th and 12th their holographic maps revealed giant sunspots 486 and 488--the same active regions that caused so much intense space weather a few weeks ago. These spots are still active. Explosions from their vicinity have been hurling clouds of gas over the Sun's limb in recent days. The Sun's 27-day rotation will soon carry the pair around to the Earth-facing side of the Sun. More solar storms are possible when they reappear on or about Nov. 19th. Meanwhile, another one of last month's giant sunspots has already reappeared. Active region 484 is peeking over the Sun's eastern limb. The sunspot looks smaller than it did in late October, but it too remains active--hurling a bright Coronal Mass Ejection into space on Nov. 13th. (spaceweather.com)

Nov 13, 2003

Just like snow in July in California, the large sunspots, flare, and CME activity on the Sun in October and early November was an unexpected surprise. Sunspots show up on the Sun more frequently during Solar Max, which occurs approximately every 11 years. But these sunspots came at a time in the Sun's cycle when we do not expect such active and large spots. The full story is available here. (Science@NASA)

Nov 4, 2003

The NOAA Space Environment Center in Boulder, Colo., reports that an intense explosion occurred on the Sun Tuesday at 2:29 p.m. EST. The violent eruption saturated X-ray detectors on NOAA’s GOES satellite, which monitors the Sun and produces a new image every minute. The full story is available here.

Noev 3, 2003

The series of solar storms that have pummeled Earth continues as forecasters at the NOAA Space Environment Center in Boulder, Colo., observed three more explosions on the Sun during the past 24 hours. The largest flare produced a Coronal Mass Ejection, CME, that could strike Earth's magnetic field by midday Monday. The full story is availalbe here.

Nov 2, 2003

Another remarkable solar flare has erupted from giant sunspot 486--an X8-class blast at 1725 UT on Nov. 2nd. Because the sunspot is nearing the Sun's western limb, this explosion was not aimed squarely at Earth. Even so, a Coronal Mass Ejection (CME) is heading our way. Auroras could appear on Nov. 3rd or 4th when the fast-moving cloud delivers a glancing blow to Earth's magnetic field. (spaceweather.com)

Oct 30, 2003

Just when we thought it was over, the Sun blasted another gigantic X-class flare directly at the Earth. The flare was detected by the GOES satellite on October 29 at 2037 GMT (3:37 pm EST), and it peaked about 10 minutes later. The full story is available here.

Oct 29, 2003

Forecasters at the NOAA Space Environment Center in Boulder, Colo., said that a powerful geomagnetic storm emitted from the Sun sped though space at 5 million mph and reached Earth Wednesday 1:13 a.m. EST. The full story is available here.

Oct 28, 2003

One of the most powerful solar flares ever recorded erupted this morning near giant sunspot 486. The explosion hurled a Coronal Mass Ejection (CME) directly toward Earth. Bright auroras could appear when the fast-moving cloud sweeps past our planet--perhaps as early as tonight. High-latitude sites such as New Zealand, Scandinavia, Alaska, Canada and US northern border states from Maine to Washington are favored, as usual, but auroras could descend to lower latitudes, too. Not all CMEs trigger auroras. Several, for instance, have swept past Earth in recent days without causing widespread displays. It all depends on the orientation of tangled magnetic fields within the electrified cloud of gas. This CME is no exception. It might cause auroras, or it might not. We will find out when it arrives. (spaceweather.com)

Oct 27, 2003

Giant sunspots 484 and 486 remain visible on the Sun, posing a continued threat for X-class solar explosions. Indeed, on Sunday, Oct. 26th, there were two such blasts--one from each sunspot. The explosions hurled Coronal Mass Ejections (CMEs) into space and somewhat toward Earth. Because of these events, sky watchers should be alert for auroras during the nights ahead. High-latitude sites such as Alaska, Canada and US northern border states from Maine to Washington are favored, as usual, but auroras could descend to lower latitudes as well. Forecasters estimate a 25% chance of severe geomagnetic storming when the incoming CMEs sweep past Earth and deliver (probably glancing) blows to our planet's magnetic field. (spaceweather.com)

Oct 24, 2003

Satellites, pagers, cell phones and electrical grids could be affected Friday afternoon by a powerful stream of energized gas and particles from the Sun. More information is available here.

Oct 23, 2003

Newly uncovered scientific data of recorded history's most massive space storm is helping a NASA scientist investigate its intensity and the probability that what occurred on Earth and in the heavens almost a century-and-a-half ago could happen again. The full story is available here.

Oct 22, 2003

Sunspot 484, which first appeared this past weekend, has grown into one of the biggest sunspots in years. Now about the size of the planet Jupiter, it's easy to see. But never look directly at the Sun! Meanwhile, say forecasters, another big sunspot could soon appear near the Sun's southeastern limb. The active region is not yet directly visible, but the Solar and Heliospheric Observatory (SOHO) has seen material being blasted over the Sun's limb from the approaching spot. Major eruptions are possible from these active regions as they rotate across the face of the Sun over the next two weeks.

Oct 19, 2003

An X-class solar flare erupted today near sunspot 484--a remarkably fast growing active region near the Sun's northeastern limb. Yesterday the spot was barely visible; now it is about 7 times wider than Earth. Because of its location near the suns's limb, today's blast was probably not Earth-directed. Sunspot 484 is, however, moving into position where it could aim solar flares and Coronal Mass Ejections our way later this week--if solar activity continues high. (spaceweather.com)

Oct 5, 2003

Earth is heading for a solar wind stream flowing from a coronal hole on the Sun. First contact with the stream is possible on Oct. 6th or 7th. High-latitude sky watchers--e.g., people in Canada, Alaska and US northern-border states like Michigan and Wisconsin--should be alert for auroras. (spaceweather.com)

Sept 27, 2003

There's a remarkable spot on the Sun this weekend. The active region, called sunspot 464, is about as wide as fifteen planet Earths lined up in a row. This means it's easy to see, but never look directly at the Sun without suitable eye protection.

Sept 27, 2003

This is a good time of year for people in the northern hemisphere to look for early-morning Zodiacal Lights. Also known as the "false dawn" because they resemble a hint of sunrise, Zodiacal Lights appear an hour or so before true dawn--a pale luminous triangle jutting upward from the eastern horizon. Look for them on dark mornings after a new moon (the next few days are ideal); rural areas with clear skies offer the best view. (spaceweather.com)

Sept 19, 2003

Earth is inside a high-speed solar wind stream flowing from a coronal hole on the Sun. Northern Lights have appeared as far south as Michigan this week. More auroras are possible this weekend, especially at high latitudes. (spaceweather.com)

Sept 12, 2003

Solar flares that scorch Earth's atmosphere are commonplace. But scientists have discovered a few each year that are not like the others: they come from stars thousands of light years away. The full story is available here. (Science@NASA)

Sept 10, 2003

New research indicates that electrons may surf on magnetic waves driven by the solar wind, and get accelerated to the point they can cause some serious damage to spacecraft orbiting the Earth. The process is a result of the interaction between the Earth's magnetic field and fluctuations in the density of the solar wind. As the density of the solar wind changes, it causes waves in the magnetic field to ripple back to the Earth. Electrons can be caught in these ripples and surf back to the Earth so fast they can damage delicate electronics in space. More information is available here.

July 13, 2003

A strong geomagnetic storm erupted on July 12th when Earth entered a high-speed solar wind stream flowing from a coronal hole on the Sun. "We were treated to an extraordinary show of Northern Lights," reports one observer in Wisconsin. "The lights were dancing wildly for about an hour and a half." Sky watchers in Minnesota, North Dakota and parts of Canada saw the display, too, in spite of the glare from a nearly-full moon. Earth is exiting the solar wind now and the chances for more such auroras this weekend are low. (spaceweather.com)

June 28, 2003

Earlier this month a large sunspot ("active region 375") crossed the Earth-facing side of the Sun and unleashed several powerful solar flares. For the past two weeks it has been out of sight on the far side of our star, but now sunspot 375 is back. It reappeared this weekend near the Sun's northeastern limb. The active region, which is about 10 times wider than our entire planet, is still an impressive sight through properly-filtered telescopes. Visit spaceweather.com for safe solar observing tips and to see recent images of the emerging spot. (spaceweather.com)

June 12, 2003

Last week Earth's magnetic field was buffeted by a high-speed solar wind stream, which triggered a geomagnetic storm. High above out planet, International Space Station science office Ed Lu saw vivid green auroras dancing outside the window, and he captured a new movie of Southern Lights from the ISS. More information is available here. (Science@NASA)

June 7, 2003

Sunspot 375 has grown impressively during the past 24 hours. It now stretches nearly 10 Earth-diameters from side to side and has developed a twisted "beta-gamma-delta" magnetic field, which poses a threat for X-class solar flares. Any explosions from its vicinity during the next few days would likely be Earth-directed. This large spot is easy to see, but never stare at the Sun! Use safe solar projection techniques. (spaceweather.com)

May 28, 2003

Big sunspot 365 unleashed a series of powerful X-class solar flares on May 27th and 28th. At least one Coronal Mass Ejection (CME) appears to be heading toward Earth. The CME could trigger auroras when it sweeps by our planet later this week. The sunspot itself is big and impressive; you can see it using safe solar projection techniques. (spaceweather.com)

May 28, 2003

The NASA mission, RHESSI, observed an intense amount of polarization associated with a gamma ray burst, indicating that the largest explosions in our Solar System are driven by magnetic fields. For more information, see the NASA press release. See the RHESSI mission page to learn more about the RHESSI mission and the RHESSI Education and Public Outreach (E/PO) page to learn more about RHESSI E/PO activities.

Last updated 01/25/2010 © UC Regents