NASA’s Solar Terrestrial Relations Observatory witnessed a dramatic solar eruption on Aug. 24, 2014 — even with one of its “eyes” partially closed.

This imagery of a coronal mass ejection, a giant explosion of solar material that explodes out into space, was captured by one of STEREO’s two spacecraft, STEREO-B, which currently has a view of the far side of the sun.

The second spacecraft, STEREO-A, however, is in a temporary phase of recording only low-resolution data. Due to an orbit that has moved it toward the other side of the sun from Earth, STEREO-A adjusted its dish-shaped antenna on Aug. 20 to point slightly away from the bright heat of the star, and consequently to a position that isn’t pointed directly at Earth. The signal still comes to Earth but is fainter, so the spacecraft will be sharing only low-resolution data until it reemerges on the other side of the sun in early 2016.

Two images of the same coronal mass ejection erupting from the sun -- hidden by the middle circles -- on Aug. 24, 2014. The left image from ESA/NASA's SOHO was captured from Earth's perspective. The right image from NASA's STEREO was captured from the far side of the sun.

Two images of the same coronal mass ejection erupting from the sun — hidden by the middle circles — on Aug. 24, 2014. The left image from ESA/NASA’s SOHO was captured from Earth’s perspective. The right image from NASA’s STEREO was captured from the far side of the sun.

The twin STEREO spacecraft provide views of the sun from a different angle than can be seen from Earth’s perspective.  When combined with images from near-Earth spacecraft like the European Space Agency and NASA’s Solar and Heliospheric Observatory, it helps scientists understand the three-dimensional shape of the sun’s brilliant CME eruptions.

Source: Karen C. Fox
NASA’s Goddard Space Flight Center, Greenbelt, Maryland