A giant sunspot, estimated to be 75,000 across, has been detected by NASA’s Solar Dynamics Observatory, which orbits Earth and has been observing the Sun for the past seven years. NASA scientists warn that this giant sunspot, called AR2665, could produce a major solar flare capable of knocking out our satellites.
Human civilization has become dependent on satellites for communications, weather forecasting, observing space, ships’ navigation on our oceans, the precise location of objects (GPS), and military intelligence and operations.
A major solar flare – an X-Class flare – can temporarily alter the upper atmosphere, creating disruptions with many different types of signal transmissions.
A GPS satellite to Earth, for example, might lose its accuracy by several yards. Power grids at ground level could blow out, and we could temporarily lose our satellite and radio communications.
NASA says that it is too early to predict how this giant sunspot will behave and what type of disruptions, if any, it might trigger.
Giant sunspot size of many Earths
NASA has estimated that this giant sunspot is about 19 times bigger than our planet. It’s enormous size means it is capable of causing an M-Class or X-Class flare. Apart from causing havoc to our satellites and communications systems, an X-Class flare could potentially place astronauts currently aboard the International Space Station and airplane pilots in danger.
Humans at ground level are protected by the atmosphere from nearly all harmful radiation and charged particles that come from the Sun. Astronauts orbiting Earth, and airline pilots who fly at high altitudes, especially near the poles, do not have the same protection.
Regarding solar flares and the dangers astronauts and airline pilots face, Ask the Astronomer, a Cornell University websites, writes:
“There are also health issues for airline pilots and astronauts. For those of us that spend most of our time on the ground, the magnetic field and the atmosphere block out almost all of the harmful radiation and charged particles.”
“This is not the case when you go up in the atmosphere. Airline pilots that fly at great altitude, and especially near the poles, are exposed to more of these.”
“The same goes for astronauts. This results in a higher incidence of cancer among airline pilots and cabin crew. Astronauts have even reported seeing flashes of light because of high energy protons hitting their eyes!”
NASA’s Goddard Space Flight Center in Greenbelt, Maryland, announced in a press release that the giant sunspot has rotated into view and is still growing.
The Goddard Space Flight Center wrote:
“This sunspot is the first to appear after the sun was spotless for two days, and it is the only sunspot group at this moment. Like freckles on the face of the sun, they appear to be small features, but size is relative.”
Giant sunspot easily visible from Earth
Any amateur astronomer with an average telescope – equipped with solar filters (important!) – should be able to see the giant sunspot easily on a clear day.
Regarding sunspot AR2665, SpaceWeather.com informs:
“Big sunspot AR2665 has decayed a little during the past 24 hours. Nevertheless, it still has an unstable magnetic field that poses a threat for moderately strong solar flares.”
“NOAA forecasters say there is a 25% chance of M-class flares on July 12th. Any explosions would be geoeffective as the sunspot is directly facing our planet.”
A giant sunspot is a photographer’s delight. Hundreds of spectacular photographs of AR2665 have been posted online.
Boni de Oliveira, who captured an image of an airplane’s silhouette with the sun and the giant sunspot behind, was quoted by SpaceWeather.com as saying:
“On July 11th, summer haze and NYC pollution allowed me properly expose the sun at a good angle for the busy air traffic route, just a few minutes before the sunset.”
“As I focused, surprise: There was a sunspot! I quickly checked SpaceWeather.com to find out it was the huge AR2665.”
What is a solar flare?
A solar flare is a very intense burst of radiation that comes from the release of magnetic energy associated with sunspots on the surface of the Sun.
Solar flares are our solar system’s biggest explosive events. These bright areas on the Sun can last from just a few minutes to several hours.
Scientists classify a solar flare according to its X-ray brightness. There are four types:
– B-Class: these are extremely docile.
– C-Class: these are small with very few noticeable consequences on Earth.
– M-Class: these are medium sized, and can cause brief radio blackouts on Earth’s polar regions.
– X-Class: these are the largest solar flares. X-Class flares can produce as much energy as a billion hydrogen bombs.
A C-Class is ten times as powerful as a B-Class, an M-Class is ten times as powerful as a C-Class, and an X-Class has the force of an M-Class times ten.
“If they’re directed at Earth, such flares and associated CMEs can create long lasting radiation storms that can harm satellites, communications systems, and even ground-based technologies and power grids. X-class flares on December 5 and December 6, 2006, for example, triggered a CME that interfered with GPS signals being sent to ground-based receivers.”
“NASA and NOAA – as well as the US Air Force Weather Agency (AFWA) and others – keep a constant watch on the sun to monitor for X-class flares and their associated magnetic storms. With advance warning many satellites and spacecraft can be protected from the worst effects.”
Solar flare could knock us back centuries
Louis Lanzerotti, distinguished research professor at New Jersey Institute of Technology’s Center for Solar-Terrestrial Research, said in April last year that a large solar flare could push our current civilization back into the Dark Ages for several years, with no mobile or landline telephones, Internet, or satellite communications, and very little electrical power.
Even though we would not like it, we would be able to manage without our mobile phones, but how long and well could be cope with no electricity? What would happen to the human race if it took many years to get everything back to normal?
Regarding a massive, well-timed solar storm for today’s global society, Prof. Lanzerotti said:
“Since the development of the electrical telegraph in the 1840s, space weather processes have affected the design, implementation and operation of many engineered systems, at first on Earth and now in space.”
“As the complexity of such systems increases, as new technologies are invented and deployed, and as humans have ventured beyond Earth’s surface, both human-built systems and humans themselves become more susceptible to the effects of Earth’s space environment.”
Video – A guide to solar flares
As this NASA Goddard video explains, flares happen when the powerful magnetic fields around and in our Sun reconnect. They are generally associated with active regions, frequently seen as sunspots, where the magnetic fields are stronger.
A giant sunspot, like the one that is on the surface of the Sun at the moment, has the capacity to trigger an X-Class flare.