10 incredible images of solar flares
By Mother Nature Network, 23 October 2012.
By Mother Nature Network, 23 October 2012.
1. Sudden and intense brightness
Solar flares are defined by NASA as a sudden, intense brightness from the sun that happens when magnetic energy in the star’s atmosphere is released into space.
In 1859, English astronomer Richard C. Carrington observed the first solar flare recorded from Earth, which he described as “two patches of intensely bright and white light.” He wrote, "While engaged in the forenoon of Thursday, Sept. 1, in taking my customary observations of the forms and positions of the solar spots, an appearance was witnessed which I believed to be exceedingly rare."
Pictured here is the sun in soft X-rays. The whitest area on the right side is a post-flare loop, which is the remnant of a solar flare.
Solar flares and other activity from our star are perhaps among the most beautiful and feared events in the solar system. Here are images of solar activity that will thrill and inspire you. (Text: Katherine Butler)
2. Massive X-class solar flare
Solar flares send a tremendous amount of light, energy and high-speed particles hurtling into space. They can last from minutes to hours and are monitored by NASA through X-rays and optical light. NASA rates solar flares according to their strength. From weakest to strongest, they are given an A, B, C, M or X rating. Each rating is 10 times stronger than the previous one.
To further fine-tune the scale, a number 1 through 9 is assigned to the rating. The ratings A through C are generally too weak to be noticed on Earth. An M rating may threaten astronauts and cause minor radio blackouts. NASA calls X-class flares “the biggest explosions in the solar system and awesome to watch.”
Just what can an X-class solar flare do? Producing as much energy as a billion hydrogen bombs, they can wreck havoc with our satellites and power grids. Pictured here is a massive X-class solar flare recorded by NASA on Aug. 9, 2011. Luckily, it sent particles streaming in the opposite direction from Earth.
3. An X-class flare just before a coronal mass ejection
A coronal mass ejection (CME) happens when a closed field in the outer solar atmosphere (also known as the corona) violently releases gas and magnetic fields into space. Anything that gets in the way of these CMEs is immediately cooked by a billion tons of matter moving several million miles per hour. CMEs are often associated with solar flares, but can happen on their own. When they reach our planet, we see them as auroras.
Pictured here is an X-class solar flare as observed by the Solar Dynamics Observatory on Nov. 3, 2011. NASA says radio transmissions were disrupted on Earth some 45 minutes after this flare. A few hours later, a CME burst off the backside of the sun, sending energy pouring in the direction of Venus.
4. The flares of Sunspot 1112
Sunspot 1112 is what NASA calls a “fast-growing sunspot…crackling with solar flares.” Here, it is seen on Oct. 21, 2010 in the southern atmosphere of the sun. NASA also notes a line or filament of magnetism stretching across the sun. This line is so vast that it exceeds the distance between the Earth and the moon.
All solar activity is driven by a solar magnetic field. Like most other occupants of our solar system, the sun has its own cycle. Every 11 or so years, the number of solar flares increases in what is known as a solar maximum. NASA notes that the next solar maximum will likely occur in 2013, sending flares and coronal mass ejections big and small towards the Earth.
5. Hot solar explosion
This solar flare was observed by the X-Ray Telescope on board the Hinode spacecraft on July 7, 2007. NASA estimates that this loop is about 10 million degrees Celsius.
Flares may look innocuous, but they can wreck havoc on Earth. Generally, the Earth’s atmosphere largely protects it from solar activity. However, when a massive, powerful flare makes its way towards our planet, we often take precautions.
October and November of 2003 were a particularly active time for the sun, according to Scientific American. Electric grids were monitored for surges, and people in southern Sweden lost power. Astronauts on board the International Space Station sought protection in a shielded service module, while pilots diverted their planes to lower atmospheres to avoid radiating themselves and passengers.
6. Magnetic connections
Here are three active areas in extreme ultraviolet light on Nov. 1 and 2, 2011. NASA points out that the magnetic reactions of the two top areas make them reach for each other. “Above them, the magnetic field lines, made visible in extreme ultraviolet light by particles spiralling along them, rise out and loop back to the sun, constantly changing their structures,” writes the space agency.
Solar flares only influence our planet when they happen on an area of the sun pointed in our direction. So will these active areas cause problems for us? As these regions will eventually rotate towards us, NASA is keeping an eye on them.
7. Flares across the sun
This image showing numerous flares across the sun was taken on March 30, 2010. In addition to solar flares and coronal mass ejections, the sun's activity includes solar energetic particles and high speed solar winds.
Solar energetic particles are “released by shocks formed at the front of coronal mass ejections and solar flares.” Coronal holes in the sun’s atmosphere, or corona, are where high-speed solar winds originate. NASA notes that when these holes are near the sun’s equator, they may impact the Earth. Likewise, when a solar wind combines with a coronal mass ejection, solar energetic particles may find their way to our planet.
8. An active sunspot
A sunspot is a dark area on the sun containing magnetic fields. In 2011, NASA reported that this sunspot, known as Sunspot 1283, ejected three solar flares and three coronal mass ejections from Sept. 5-7. This photo shows the sun on Sept. 7, 2011.
On the right side of the image, a "giant plume of solar material - ionized gas called plasma" can be seen erupting from Sunspot 1283, according to NASA.
Plasma is electrically conducted gas and solar flares generally occur above loops of plasma. Experts note that evaporated plasma tends to be the source of the hottest temperatures in solar flares.
9. A powerful solar flare
This image, taken on Oct. 28, 2003, shows the most powerful solar flare ever recorded up until this date. During this time, the sun experienced the most massive space storm in at least a century and a half.
A similar storm took place in 1859, causing what experts call the perfect space storm. “Within hours, telegraph wires in both the United States and Europe spontaneously shorted out, causing numerous fires,” NASA writes. During the 1859 solar storm, the aurora borealis or northern lights, could be seen as far south as Rome.
10. Plasma above the sun's surface
Plasma makes another appearance in this extreme ultraviolet image showing the sun on June 16, 2011. NASA recorded several spurts of plasma over the sun that flickered for 13 hours on this day. “This wavelength captures ionized helium at about 60,000 degrees not far above the sun's surface,” NASA writes.
The activity of the sun can be beautiful and brilliant. But will it ever be deadly? NASA says that even the biggest solar flares could not destroy the Earth. However, the electromagnetic radiation and energetic particles have and will continue to threaten and disrupt our power grids, satellites and more. So while our physical selves may be safe, our cell phones are not.
[Source: Mother Nature Network. Edited.]