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Current extent of the auroral oval in the northern hemisphere (left) and
southern hemisphere (right).
Click for full image (POES Auroral Activity page).
Interplanetary magnetic field and solar wind (data averaged over last 15 minutes).
Explanation of Real-Time Solar Wind data dials
What's Up in Space -- 11 Sep 2005
AURORA ALERT
A strong geomagnetic storm is underway, and it is causing some beautiful displays of
Northern Lights.
ACTIVE SUN
Solar activity is very high. Earth-orbiting satelites have detected seven X-class solar
flares in recent days, including an X17-class monster-flare on Sept. 7th. NOAA
forecasters say there's a 75% chance of more X-flares during the next 24 hours,
possibly causing radio blackouts and radiation storms.
The source of all this activity is giant sunspot 798:
The sunspot has grown so large, you can now see it with the unaided eye--but never look directly at the sun!
A s t r o A l e r t
11 September 2005
MIDDLE LATITUDE AURORAL ACTIVITY WARNING - 11-14 SEPTEMBER
A middle latitude auroral activity warning has been issued for the next
several days. Intense solar flare activity continues. The associated high
velocity coronal mass ejections are beginning to become more heavily directed
toward the Earth. Several smaller impacts were observed over the last 24 to
48 hours from solar activity that occurred when sunspot complex 10808 was on
the eastern limb of the Sun. But now, the region has rotated sufficiently far
to produce stronger Earthward-directed impacts.
The latest impact was observed near 01:19 UTC on 11 September (9:19 pm EDT on 10 September). This disturbance has the potential to produce periods of minor to major auroral storm conditions during the next 12 to 24 hours. Combining this disturbance with several others that are anticipated during the next 48 hours may result in a more volatile mixture of space weather conditions, perhaps capable of producing significant auroral storm activity during the next week. Observers across the United States and Europe (even toward the lower latitudes of the central/southern states) may spot periods of activity during the next week.
Active sunspot Region 10808 remains exceptionally complex and volatile. It has produced two X-class flares within the last 12 hours (the largest being a class X2.1 event at 22:11 UTC (6:11 pm EDT) on 10 September. Additional strong X-class flares are expected in the coming days. With each passing day, the trajectory of the ejected mass from these events will impact the Earth more directly, resulting in greater opportunities for observers to spot auroral activity.
The official auroral activity warning statement is appended below. Note the statement indicating there is a good chance the warning may be extended beyond the 14 September deadline.
MIDDLE LATITUDE AURORAL ACTIVITY WARNING
Issued: 01:45 UTC on 11 September 2005
Solar Terrestrial Dispatch
VALID BEGINNING AT: EFFECTIVE IMMEDIATELY
VALID UNTIL: 23:00 UTC (6 pm EST) ON 14 SEPTEMBER
HIGH RISK PERIOD: 11-13 SEPTEMBER (UTC DAYS)
MODERATE RISK PERIOD: 11-14 SEPTEMBER
PREDICTED ACTIVITY INDICES: 50, 40, 40, 20 (11 - 14 SEPTEMBER)
POTENTIAL MAGNITUDE OF MIDDLE LATITUDE AURORAL ACTIVITY: MODERATE TO HIGH
POTENTIAL DURATION OF THIS ACTIVITY: MAIN BELT = 24-72 HOURS
MINOR BELT = 72-96 HOURS
ESTIMATED OPTIMUM OBSERVING CONDITIONS: NEAR OR AFTER LOCAL MIDNIGHT
EXPECTED LUNAR INTERFERENCE: LOW TO MODERATE
OVERALL OPPORTUNITY FOR OBSERVATIONS FROM MIDDLE LATITUDES: FAIR TO GOOD
AURORAL ACTIVITY *MAY* BE OBSERVED APPROXIMATELY NORTH OF A LINE FROM...
(THIS LINE IS VALID *ONLY* IF FAVORABLE STORM CONDITIONS OCCUR)
OREGON TO SOUTHERN IDAHO AND NORTHERN UTAH TO WYOMING TO NEBRASKA TO
NORTHERN MISSOURI TO SOUTHERN ILLINOIS TO KENTUCKY TO VIRGINIA.
ACTIVITY *MAY* ALSO BE OBSERVED APPROXIMATELY NORTH OF A LINE FROM...
(THIS LINE IS VALID *ONLY* IF FAVORABLE STORM CONDITIONS OCCUR)
CENTRAL FRANCE TO NORTHERN SWITZERLAND TO SOUTHERN GERMANY TO THE CZECH
REPUBLIC TO POLAND TO CENTRAL RUSSIA.
NEW ZELAND AND SOUTHEASTERN AUSTRALIA SHOULD ALSO BE ABLE TO SPOT PERIODS
OF ACTIVITY.
This warning will remain valid through 24:00 UTC (6 pm EDT) on 14 September, with a good chance that it will be extended beyond the 14th. It will be updated or allowed to expire at that time. It will be updated or allowed to expire at that time. For updated information, visit: www.spacew.com/aurora/forum.html. For real-time plots of current activity, visit: www.spacew.com/plots.html
PLEASE REPORT VALID OBSERVATIONS OF AURORAL ACTIVITY TO: www.spacew.com/submitsighting.html
Space Weather News for Sept. 10, 2005
Intense Solar Activity Continues
Solar activity remains very high and shows no signs of abating. Sunspot 798/808 has
unleashed seven X-class solar flares since Sept. 7th. Forecasters say there's a
75% chance of more X-flares during the next 24 hours, possibly causing radio
blackouts and radiation storms.
Coronal mass ejections hurled into space by these explosions could hit Earth's magnetic field in the days ahead. Sky watchers, particularly in northern places like Canada and Alaska, should remain alert for auroras. The best time to look is local midnight.
The sun's 27-day rotation is slowly turning sunspot 798 to face Earth. Explosions in the coming week will be increasingly Earth-directed, raising the possibility of geomagnetic storms and auroras over the continental United States, Europe and Australia.
Space Weather News for May 14, 2005
Weekend Aurora Watch
A coronal mass ejection (CME) is heading for Earth following a strong solar flare on May 13th.
Sky watchers should be alert for auroras when the cloud arrives on May 14th or 15th.
The display, if it materializes, will be best over high latitudes--e.g., Alaska and Canada. But CMEs sometimes spark auroras over lower latitudes, too, so everyone should keep an eye on the sky this weekend.
A s t r o A l e r t
14 May 2005
MAJOR SOLAR FLARE PROMPTS AN AURORA WARNING
The Sun is known for producing energetic spurts of activity, even during
the less active periods around the solar sunspot minimum years. We are now a
little more than one year from reaching the solar minimum. The frequency of
energetic solar events has diminished over the last year, as has the number
of sunspots that pepper the face of the Sun. But as has been the case with
most solar cycles in recorded history, the Sun is not always quiet. It
occasionally hiccups and produces large and complex sunspots capable of
influencing space weather at the Earth.
We are currently experiencing one of those 'hiccups.' Several large sunspots have appeared recently that have had the potential to produce energetic solar flare activity. Region 10759, now nearing the central solar meridian, spawned a major class M8.0 solar x-ray flare at 16:57 UTC on 13 May. The event was associated with strong radio bursts across the spectrum. Such bursts have the potential to disrupt cellular phone services when the Sun is aligned with the direction of cellular signal propagation (most dominantly near sunrise and sunset when solar elevation angles are more in-line with cellular signal trajectories). This event has also been blamed for producing a weak space radiation storm, where energetic particles (protons) arrive from the Sun travelling at near relativistic velocities. Such storms have the potential to affect the health and stability of satellites orbiting the Earth.
Perhaps most significantly, this solar flare was associated with a coronal mass ejection that appears to be directed squarely at the Earth. Sometime on 15 May (perhaps during the early to mid UTC hours of 15 May, corresponding to the late evening to early morning hours of 14/15 May for North Americans), this cloud of solar plasma will impact the Earth's magnetosphere and energize it. What follows will depend upon the energy of the impact and the orientation of the imbedded solar magnetic fields that interact with the Earth's magnetic field. If the imbedded magnetic fields are oriented appropriately, they will generate a potentially strong geomagnetic storm and produce auroral activity ("northern lights") that may become visible across extensive middle latitude regions (central United States through perhaps central Europe, New Zealand and southern Australia).
Given our proximity to the solar minimum and the decreasing frequency of auroral storm events, it may be prudent to watch the skies carefully for activity this weekend (particularly on Saturday and Sunday nights). Current information can be found at www.spacew.com or www.sec.noaa.gov. Those who succeed in observing activity are encouraged to report their observations to the Global Auroral Activity Observation Network at: www.spacew.com/submitsighting.html. A near-realtime accounting of reported sightings can be found at: www.spacew.com/www/auroras.html.
This disturbance is expected to last roughly 18 to 24 hours and may only provide an opportunity to observe auroral activity for one evening. There may be additional opportunities to observe activity over the coming week, as the active sunspot complex responsible for producing this disturbance may yet spawn additional major flares and Earthward-directed CME's in the days ahead.
A copy of the official Middle Latitude Auroral Activity Warning is appended below for your convenience.
MIDDLE LATITUDE AURORAL ACTIVITY WARNING
Issued: 05:05 UTC on 14 May 2005
Solar Terrestrial Dispatch
www.spacew.com
VALID BEGINNING AT: 00:00 UTC 15 MAY 2005
VALID UNTIL: 23:00 UTC (6 pm EST) ON 16 MAY
HIGH RISK PERIOD: 15 MAY (UTC DAYS)
MODERATE RISK PERIOD: 15-16 MAY
PREDICTED ACTIVITY INDICES: 14, 70, 30, 12 (14 - 17 MAY)
POTENTIAL MAGNITUDE OF MIDDLE LATITUDE AURORAL ACTIVITY: MODERATE TO HIGH
POTENTIAL DURATION OF THIS ACTIVITY: MAIN BELT = 12-18 HOURS
MINOR BELT = 18-24 HOURS
ESTIMATED OPTIMUM OBSERVING CONDITIONS: NEAR OR PRIOR TO LOCAL MIDNIGHT
EXPECTED LUNAR INTERFERENCE: LOW
OVERALL OPPORTUNITY FOR OBSERVATIONS FROM MIDDLE LATITUDES: GOOD
AURORAL ACTIVITY *MAY* BE OBSERVED APPROXIMATELY NORTH OF A LINE FROM...
(THIS LINE IS VALID *ONLY* IF FAVORABLE STORM CONDITIONS OCCUR)
OREGON TO SOUTHERN IDAHO AND NORTHERN UTAH TO WYOMING TO NEBRASKA TO
NORTHERN MISSOURI TO SOUTHERN ILLINOIS TO KENTUCKY TO VIRGINIA.
ACTIVITY *MAY* ALSO BE OBSERVED APPROXIMATELY NORTH OF A LINE FROM...
(THIS LINE IS VALID *ONLY* IF FAVORABLE STORM CONDITIONS OCCUR)
CENTRAL FRANCE TO NORTHERN SWITZERLAND TO SOUTHERN GERMANY TO THE CZECH
REPUBLIC TO POLAND TO CENTRAL RUSSIA.
NEW ZELAND AND SOUTHEASTERN AUSTRALIA SHOULD ALSO BE ABLE TO SPOT PERIODS
OF ACTIVITY IF SUITABLE STORM CONDITIONS MATERIALIZE DURING DARKNESS.
This warning will remain valid through 24:00 UTC (6 pm EDT) on 16 May. It will be updated or allowed to expire at that time. For updated information, visit: www.spacew.com/aurora/forum.html. For real-time plots of current activity, visit: www.spacew.com/plots.html
PLEASE REPORT VALID OBSERVATIONS OF AURORAL ACTIVITY TO: www.spacew.com/submitsighting.html
What's Up in Space -- 22 January 2005
EURORAS
Bright auroras spread across northern Europe on January 21st soon after a coronal mass ejection (CME) crashed into Earth's magnetic field. The impact sparked a severe geomagnetic storm and, by many accounts, the best aurora-display in years.
What's Up in Space -- 21 January 2005
IMPACT!
A coronal mass ejection has just swept past Earth, causing our planet's magnetic field
to shake and glow. A severe geomagnetic storm is developing. If it's dark where you
live, go outside and look for auroras.
BIG BANG
Giant sunspot 720 erupted again on Jan. 20th unleashing a powerful X7-class solar flare. The blast hurled a coronal mass ejection (CME) into space and sparked the strongest radiation storm since October 1989.
What is a radiation storm? Look at this SOHO coronagraph image of the explosion. Each speckle is a solar proton striking the spacecraft's digital camera. So many protons accelerated to light speed by the explosion and streaming past Earth--that's a "radiation storm."
Note: ISS astronauts are in no danger from the storm because they orbit Earth inside our planet's protective magnetic field. Plus, the station itself is well shielded.
Visit Spaceweather.com for more information and updates
A s t r o A l e r t
21 January 2005
Solar Terrestrial Dispatch
www.spacew.com
STRONG X-CLASS SOLAR FLARE, RADIATION STORM AND AURORA WARNING
A lot has happened in the last 24 to 36 hours. A strong class X7.1 solar
x-ray flare was observed on 20 January that resulted in the strongest
high-energy space radiation storm since 1989 (last solar cycle). Energetic
protons at greater than 100 MeV seldom increase in density above 1 particle
flux units (pfu). However, during this major solar flare, energetic protons
at greater than 100 MeV increased in density to over 650 pfu. There is
evidence that protons at greater than 500 MeV (relativistic energies)
bombarded the Earth for several hours after the event. This was the "hardest"
proton event since the powerful events of 1989. Energetic proton populations
were so intense that neutron densities at ground level over the high latitude
regions suddenly increased by more than 50% above background levels,
resulting in one of the strongest Ground Level Events of this solar cycle.
Energetic protons from this flare travelled the distance from the Sun to the Earth at almost the same time that it took light from the Sun to reach the Earth. This is remarkable given the mass of protons and the energy required to accelerate them to very near the speed of light.
The arrival of these energetic protons at the Earth can result in degradation in the efficiency of solar arrays in orbit to convert sunlight to electricity. As a result, many spacecraft may have observed permanent losses of electrical generation power following this event. The protons also intensely ionized the Earth's high and polar latitude ionospheres, resulting in the complete loss of high frequency radio communications across the high and polar latitudes regions.
A strong coronal mass ejection was associated with this solar flare, with at least a portion of the ejected mass appearing to have an Earthward-directed component. The impact of this disturbance (which is possible anytime over the next 24 to 36 hours) could result in periods of moderate to strong auroral activity across many dark-sky middle and low latitude regions. A middle latitude auroral activity warning has been issued together with a low-latitude auroral activity watch (see below).
Region 10720, which has been solely responsible for all of this activity, will be departing the visible side of the Sun and rotating behind the western limb over the next few days. As a result, the influence of this powerful active region will diminish substantially. Whether it survives its transit of the far side of the Sun and reappears two weeks later on the eastern side of the Sun is an unknown question. The region has been undergoing fairly substantial decay over the last few days. Thus, most forecasters believe it will probably diminish in size and complexity as it passes around the far side of the Sun.
Observers interested in seeing the "northern lights" are strongly encouraged to watch the skies tonight and tomorrow night.
The low latitude aurora watch is essentially the same as the middle latitude aurora warning (the same boundary lines apply). Thus, only the mid-latitude aurora warning is appended below, with the understanding that a low-latitude watch also exists. Visit www.spacew.com for regular updates and details.
MIDDLE LATITUDE AURORAL ACTIVITY WARNING
Upgraded: 20:10 UTC on 21 January 2005
Solar Terrestrial Dispatch
www.spacew.com
VALID BEGINNING AT: EFFECTIVE IMMEDIATELY
VALID UNTIL: 23:00 UTC (6 pm EST) ON 23 JANUARY
HIGH RISK PERIOD: 21-22 JANUARY (UTC DAYS)
MODERATE RISK PERIOD: 21-23 JANUARY
PREDICTED ACTIVITY INDICES: 70, 40, 20, 12 (21 - 24 JANUARY)
POTENTIAL MAGNITUDE OF MIDDLE LATITUDE AURORAL ACTIVITY: MODERATE TO HIGH
POTENTIAL DURATION OF THIS ACTIVITY: MAIN BELT = 12-18 HOURS
MINOR BELT = 18-36 HOURS
ESTIMATED OPTIMUM OBSERVING CONDITIONS: NEAR OR AFTER LOCAL MIDNIGHT
EXPECTED LUNAR INTERFERENCE: MODERATE
OVERALL OPPORTUNITY FOR OBSERVATIONS FROM MIDDLE LATITUDES: GOOD
AURORAL ACTIVITY *MAY* BE OBSERVED APPROXIMATELY NORTH OF A LINE FROM...
(THIS LINE IS VALID *ONLY* IF FAVORABLE STORM CONDITIONS OCCUR)
EXTREME NORTHERN CALIFORNIA TO NORTHERN NEVADA TO UTAH TO COLORADO TO
SOUTHERN KANSAS AND NORTHERN OKLAHOMA TO ARKANSAS TO TENNESSEE TO SOUTH
CAROLINA.
ACTIVITY *MAY* ALSO BE OBSERVED APPROXIMATELY NORTH OF A LINE FROM...
(THIS LINE IS VALID *ONLY* IF FAVORABLE STORM CONDITIONS OCCUR)
NORTHERN SPAIN AND PORTUGAL TO SOUTHERN FRANCE TO ITALY TO ROMANIA TO
UKRAIN TO SOUTHERN RUSSIA.
This warning will remain valid through 23:00 UTC (6 pm EST) on 23 January. It will be updated or allowed to expire at that time. For updated information, visit: www.spacew.com/aurora/forum.html. For real-time plots of current activity, visit: www.spacew.com/plots.html
PLEASE REPORT VALID OBSERVATIONS OF AURORAL ACTIVITY TO: www.spacew.com/submitsighting.html
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