The is the first complete image of the solar far side, the half of the sun invisible from Earth.
Earth is still waiting for the arrival of the CME unleashed June 7, 2011 but the forecasts of the glancing blow have been substantially reduced. The Sun unleashed an M-2 solar flare, an S-1 radiation storm and a spectacular coronal mass ejection in the early hours of June 7, 2011.
Although STEREO is primarily a solar mission, UK scientists were able to use the Heliospheric Imagers aboard STEREO to monitor variations in the brightness of stars.
Four years after launch NASA's two STEREO spacecraft are now 180 degrees apart and able to image the entire Sun.
NASA will score big on super SUN-day at 11 a.m. EST, Sunday, Feb. 6, with the release online of the first complete view of the sun's entire surface and atmosphere.
Solar storms don't always travel in a straight line. But once they start heading in our direction, they can accelerate rapidly, gathering steam for a harder hit on Earth's magnetic field.
One of the fastest CMEs in years was captured by the STEREO COR1 telescopes on August 1, 2010.
The STEREO spacecraft caught this spectacular eruptive prominence in extreme UV light over a 19-hour period between Apr. 12-13, 2010.
Imagine holding the entire sun in the palm of your hand. Now you can with the help of a new iPhone app developed by NASA-supported programmers.
Sometimes you really can believe your eyes. That's what NASA's STEREO is telling researchers about a controversial phenomenon on the sun known as the "solar tsunami."
The twin STEREO spacecraft captured this large and dramatic prominence eruption over about a 30-hour period between Sept. 26-27, 2009.
NASA′s Solar Terrestrial Relations Observatory (STEREO) spacecraft has spotted the first major activity of the new solar cycle.
STEREO spacecraft images and in situ measurements combine to show a complete picture of CMEs that paves the way for predicting solar storms like meteorologists predict hurricanes.
Two places on opposite sides of Earth may hold the secret to how the moon was born.
January 24, 2009 marks the point at which the two STEREO spacecraft reach 90 degrees separation, a condition known as quadrature. Since the two STEREO spacecraft went into orbit around the Sun at the beginning of 2007, they have been slowly drifting apart from Earth, and from each other. After two years in solar orbit, the two spacecraft have finally reached quadrature.
You would think that, after 13-years of historic comet discoveries with SOHO and two years of amazing STEREO/SECCHI observations and discoveries, we had put a check-mark in most of the boxes for comet-related achievements. But last week, Australian comet-hunter Alan Watson helped us with yet another historic achievement -- the recovery of a comet! Here's how it unfolded.
Solar flares are the most powerful explosions in the solar system. Packing a punch equal to a hundred million hydrogen bombs, they obliterate everything in their immediate vicinity. Not a single atom should remain intact. At least that's how it's supposed to work.
Coronal jets are small-scale transient ejections of hot gases, or plasma, occurring in the solar atmosphere. During a typical event, about a million tons of matter are ejected at speeds reaching a million miles per hour over a few minutes' time.
Sequences of STEREO satellite images of a solar tsunami blasting across the Sun's million degree atmosphere.
Boosted to almost the speed of light, "killer electrons" can knock out computers, pierce spacesuits and damage the tissues of astronauts.