Sunspot Forming

AROUND THE BEND? The Earth-facing side of the sun is mostly blank and quiet. This could change in the days ahead as a new sunspot emerges over the sun’s southeastern limb. NASA’s Solar Dynamics Observatory can see the active region’s magnetic canopy, which is towering over the limb in advance of the sunspot itself:

The core of the active region should show itself no later than Tuesday. Meanwhile, solar activity is low. NOAA forecasters estimate a mere 1% chance of M- or X-class solar flares.


Another Solar Flare

ANOTHER BIG SUNSPOT: As one big sunspot (AR1515) turns away from Earth, another one is turning toward our planet. AR1520, now emerging over the sun’s southeastern limb, stretches more than 127,000 km (10 Earth diameters) from end to end:

AR1520 has a ‘beta-gamma’ magnetic field that harbors energy for M-class solar flares. So far, however, the sunspot’s magnetic canopy is crackling with lesser C-flares. The calm before the storm? NOAA forecasters estimate an 80% chance of M-flares during the next 24 hours.


Very Large Sunspot Coming Our Way

BIG SUNSPOT: One of the largest sunspot groups in years rotated over the sun’s northeastern limb on May 6th. With a least four dark cores larger than Earth, AR1476 sprawls more than 100,000 km from end to end, and makes an easy target for backyard solar telescopes. Amateur astronomer Alan Friedman sends this picture of the behemoth from his backyard in Buffalo, NY:

“AR1476 is firecrackler,” says Friedman.

Indeed, the active region is crackling with impulsive M-class solar flares. Based on the sunspot’s complex ‘beta-gamma’ magnetic field, NOAA forecasters estimate a 75% chance of more M-flares during the next 24 hours. There is also a 10% chance of powerful X-flares.

“This one is going to be fun as it turns to face us!” predicts Friedman. He might be right


Sunspot AR 1429 Continues to Erupt

INCREDIBLE SUNSPOT AR1429: Big sunspot AR1429, the source of so many strong flares and geomagnetic storms earler this month, is still erupting. The active region produced a significant coronal mass ejection on March 24th at 00:39 UT. Because of the sunspot’s location on the far side of the sun, this particular CME will not hit Earth. An animated forecast track prepared by analysts at the Goddard Space Weather Lab shows the trajectory of the expanding cloud:

The leading edge of the CME is espected to arrive at the STEREO-B spacecraft on March 25th at 13:08 UT (+/- 7 hours). None of the inner panets will be affected.

Since March began, sunspot AR1429 has propelled CMEs into every corner of the solar system, stirring up stormy space weather around every planet and spacecraft. If the sunspot remains active for another week or so, it will turn back toward Earth for a new round of geoeffective eruptions.


Incoming CME 3/6

STRONG SOLAR ACTIVITY: Solar activity is now high. Big sunspot AR1429, which emerged on March 2nd, is crackling with strong flares. This morning brought the strongest so far–an X1-class eruption on March 5th at 0413 UT. NASA’s Solar Dynamics Observatory recorded the extreme ultraviolet flash:

Update: The explosion also hurled a bright CME into space. According to analysts at the Goddard Space Weather Lab, the CME will probably miss Earth, although it will hit Mercury and Venus. An animated forecast track shows the likely progression of the cloud.

Even if this CME misses, high-latitude sky watchers should still be alert for auroras in the nights ahead. An M2-class eruption from the same sunspot on March 4th produced another, wider CME that might yet intersect Earth. The cloud is expected to deliver a glancing blow to our planet’s magnetic field on March 6th at 04:30 UT (+/- 7 hr).


New Sunspot

RING-SHAPED SUNSPOT: New sunspot AR1413 is emerging in the shape of a ring. This two-day movie from the Solar Dynamics Observatory shows the sunspot’s geometric development:

Does the magnetic architecture of this unusual spot harbor energy for strong flares? Magnetograms appear to show some mixing of polarities between the left and right halves of the ring, which could lead to explosive instabilities. So far, however, solar activity remains low.


X-Flare Incoming

SATURDAY X-FLARE: Behemoth sunspot 1302 unleashed another strong flare on Saturday morning–an X1.9-category blast at 0940 UT. NASA’s Solar Dynamics Observatory recorded the extreme ultraviolet flash:

The movie also shows a shadowy shock wave racing away from the blast site. This is a sign that the blast produced a coronal mass ejection (CME). Analysts at the Goddard Space Weather Lab say the CME could deliver a glancing blow to Earth’s magnetic field on Sept. 26 at 14:10 UT (+/- 7 hours);

New Sunspot To Watch

UNSPOT CONJUNCTION: A new sunspot (AR1289) is growing rapidly in the sun’s eastern hemisphere. The International Space Station drew attention to it this morning when the solar-paneled spacecraft flew almost directly in front of the sunspot’s dark core:


Maximilian Teodorescu took the picture from Magurele, Romania. “The space station made a very nice couplet with sunspot AR1289,” he says. “This was the second ISS transit of the sun in three days for my location.”