Last Friday, August 31, the star at the center of our Solar System belched. A long tendril of solar material in the Sun’s corona (its atmosphere) spewed forth — hurtling away into space at over 900 miles per second.

This event, known as a coronal mass ejection (CME), is a common occurrence — happening anywhere from every five days to every eight hours. CMEs release a tremendous amount of electronmagnetic radiation and matter in the form of plasma. Sometimes, aimed straight at us.

The impact on Earth can be benign — such increased activity near the magnetic poles resulting in more intense and beautiful auroral displays — or it can be more severe — damaging satellites and knocking out transmission facilities on the electrical grid.

It’s amazing the ability that we have to understand the Sun nowadays. A new era in solar research began at the end of 1995 with the launch of the Solar and Heliospheric Observatory (SOHO). The SOHO spacecraft sits permanently at the Sun-Earth L1 point — a gravitational eddy which moves in sync with the Earth. From there, it take measurements to help predict solar weather.

However, one limitation of SOHO is that it sees the Sun from the same angle that we do. The Solar Terrestrial Relations Observatory (STEREO) mission, which launched in 2006, was intended to augment our view — in effect, giving us a 360 degree image of the Sun at any time.

It uses two spacecraft (named, dryly, A and B) with two different heliocentric orbital periods to give us a peek at the far side of the Sun. Data from this mission has led to improvements in how we forecast CMEs which is important for power companies, satellite infrastructure, and the airlines.

In fact, NASA’s newest mission, Solar Dynamics Observatory (SDO), delves even deeper. Launched in February of last year, it’s looking into the Sun’s magnetic field — specifically, its composition and how it’s created. By understanding more about the Sun’s magnetic energy, scientists hope to learn how that energy is transformed into various phenomena, such high-energy particles and the solar wind.

The video above includes footage from all three missions. Enjoy a stunning look at the Sun that wasn’t even possible just 20 years ago.

Be Sociable, Share!

•