On Feb. 25, 2007, NASA scientists were calibrating some cameras aboard the STEREO-B spacecraft and they pointed the instruments at the sun. Here is what they saw.
When scientists announce they're about to calibrate their instruments, science writers normally put away their pens. It's hard to write a good story about calibration.
"What an extraordinary view," says Lika Guhathakurta, STEREO Program Scientist at NASA headquarters. The fantastically-colored star is our own sun as STEREO sees it in four wavelengths of extreme ultraviolet light. The black disk is the Moon. "We caught a