The upper left corner of this image of the sun shows the biggest and most complex sunspot visible on the sun as of May 9, 2012. It has produced 7 M-class flares so far, but has not produced any coronal mass ejections that could cause geomagnetic storms near Earth.
Sunspot AR 1476 compared to the size of Earth. Image released May 10, 2012.
Sunspot AR 1476 compared to the size of Jupiter. Image released May 10, 2012.
The monster sunspot AR1476 (top left) turns into view in this image from NASA's Solar Dynamics Observatory released on May 7, 2012.
The monster sunspot group AR 1476 (upper left) measures more than 60,000 miles from end to end. NASA's Solar Dynamics Observatory spacecraft snapped this photo on May 7, 2012.
Sunspot 1302 has already produced two X-flares (X1.4 on Sept. 22nd and X1.9 on Sept. 24th). Each of the dark cores in this image from SDO is larger than Earth, and the entire active region stretches more than 100,000 km from end to end. The sunspot's magnetic field is currently crackling with sub-X-class flares that could grow into larger eruptions as the sunspot continues to turn toward Earth.
Another CME has lifted off Region 1402. Forecasters at NOAA NWS Space Weather Prediction Center are monitoring the energetic particle levels to see if this new CME-flare event, will produce more of these particles. The flare, a C6 x-ray event at 26/0542Z, was a long duration flare (meaning from the flare peak to the flare end was over 30 minutes) and had an associated partial-halo CME. This CME looks to be none Earth directed, but further analysis is being done.
The gigantic sunspot in the upper left of this image is about 50,000 miles (80,000 km) long and was observed on the sun by NASA's Solar Dynamics Observatory on Nov. 3, 2011.
This image from one of the cameras on NASA's Solar Dynamics Observatory shows the sun as it appeared on Jan. 24, 2012. The sunspot grouping in the upper right of the sun's disk is known as Active Region 1402, a sunspot region responsible for recent solar storms. The prominent spot on the left is region 1408.
A new sunspot collided with an existing sunspot which built up a highly sheared magnetic configuration. This resulted in a solar flare on December 13, 2006.
A close-up of one active region on the sun, seen in profile in extreme ultraviolet light, produced an interesting display of dynamic and frenetic sputtering over three days (Aug. 28-30, 2011).
Sunspot 1302 poses a continued threat for X-class solar flares in late September 2011.
Map of velocities in the sunspot as measured using the Doppler effect. Blue implies that the gas is moving towards us - this corresponds to an upward motion on the solar surface. Red implies that the gas is moving away from us - this corresponds to a downward motion on the solar surface. The net-like pattern surrounding the sunspot is solar granulation. The field of view corresponds to 24000 km on the sun.
SDO watched as areas of a sunspot group changed substantially over 2.5 days (Aug. 21-23, 2011).
A photo of a sunspot taken in May 2010, with Earth shown to scale. The image has been colorized for aesthetic reasons. This image with 0.1 arcsecond resolution from the Swedish 1-m Solar Telescope represents the limit of what is currently possible in terms of spatial resolution.
This ultraviolet image of the sun shows large sunspot group AR 9169 as the bright area near the horizon. The relatively cool dark regions have temperatures of thousands of degrees Celsius, in contrast to the bright glowing gas flowing around the sunspots, which have a temperature of over one million degrees Celsius. Large sunspot group AR 9169 moved across the sun during September 2000.
Portions of sunspot groups can shift over time. One core area of Sunspot 1117 emerged, and then slid over and merged with another core area over three days (Oct. 25-27, 2010) to form a much larger, active sunspot region. Each dark umbra (darkest area) is as wide as Earth.
The Swedish 1-m Solar Telescope on La Palma recorded this part of the largest sunspot in Active Region 10030, on July 15, 2002. Phase-Diversity Technique post-processing has rendered this the highest-resolution solar image ever. Marks around the edge of the image show the scale: 1000 km between marks. The central part of the sunspot ("the umbra") looks dark because strong magnetic fields there stop upwelling hot gas from the solar interior.
The subsurface structure (sound speed) below a sunspot as derived from Doppler measurements by MDI. Using the technique of time-distance helioseismology, three planes are shown. The surface intensity shows the sunspot with the dark central umbra surrounded by the somewhat brighter, filamentary penumbra. The second plane cuts from the surface to 24000 km deep showing areas of faster sound speed as reddish colors and slower sound speed as bluish colors. The third plane (bottom) is a horizontal cut at a depth of 22000 km showing the horizontal variation of sound speed.
This large field-of-view image of sunspots in Active Region 10030 was observed on July 15, 2002. Researchers colored the image yellow for aesthetic reasons.
SOHO spacecraft viewed these sunspots on March 7, 2011.
A spicule is like a pipe as wide as a state and as long as the Earth, filled with hot gas moving 50,000 kilometers per hour. The "pipe" is not made of metal, rather a transparent magnetic field. Thousands of young spicules form on the active Sun. This image is one of the highest resolution taken of these enigmatic solar flux tubes. What determines the creation and dynamics of spicules remains a topic of active research.
Two sunspots simulated in 3-D by model data, viewed from above and in cross-section below surface.
Transition from inner umbra region (right) to outer penumbra region (left) in one sunspot.
Images taken July 1 and 2, 2010 by the New Solar Telescope at the Big Bear Solar Observatory reveals up-close details of a sunspot like never before. Full Story.
Probably the largest sunspot that we have observed in several years has rotated to the center of the Sun (Nov. 6-8, 2011) as viewed by SDO where effects from solar storms could possibly be felt here at Earth. This large sunspot is accompanied by a good many smaller sunspots as well. It has already blasted out several medium- to large-sized solar flares and has the potential to hurl out more. How large is it? The group extends more than 100,000 km from end to end and each of the several dark cores is larger than Earth.
The simulation shows the interface between a sunspot's umbra (dark center) and penumbra (outer region) shows a complex structure with narrow, almost horizontal (lighter to white) filaments embedded in a background with more vertical (darker to black) magnetic field.
It appears that these pairs of sunspots are peering out from the Sun. Sunspots are a little cooler (7,000 degrees F.) and thus appear darker than the Sun's surface (10,000 degrees F.). Notice how the surface looks dimpled everywhere you look: each of these granules is the top of a convection cell where hot fluid rises up, spreads out, then sinks back over about 20 minutes. Each granule is about 620 miles across.
Skywatcher Kenneth Farmer took this photo of the sun showing AR1429 sunspot region on March 7, 2012. He says: "I live in San Francisco and took this photo yesterday through a telescope (with a solar filter) of the AR1429 sunspot region. This is the area that generated the massive solar flare."
During the initial stage of sunspot emergence and cooling, the formation of H2 may trigger a temporary "runaway" magnetic field intensification. The magnetic field prevents the flow of energy from inside the sun to the outside, and the sunspot cools as the energy shines into space. They form hydrogen molecules that take half the volume of the atoms, thus dropping pressure and concentrating the magnetic field, and so on.
The massive sunspot region AR1429 has been particularly active since it emerged on March 2, 2012.
This view of the sun taken by NASA's Solar Dynamics Observatory shows the active sunspot region 1429 as it appeared at 11:30 p.m. ET on March 5, 2012 to the spacecraft's Helioseismic and Magnetic Imager. The region unleashed a major X-class flare just one minute before this view was taken.