WAITING FOR THE SOLAR WIND: A narrow stream of solar wind that was supposed to hit Earth's magnetic field yesterday, did not. The tardy stream is still en route and may arrive later today, bringing with it a 25% chance of polar geomagnetic storms. Arctic sky watchers should be alert for auroras after nightfall. Free: Aurora alerts.
DID COMET 45P LOSE ITS TAIL? At the end of December 2016, Comet 45P/Honda-Mrkos-Pajdusakova plunged toward the sun with a long tail streaming behind it. Now the comet is heading for Earth for a close encounter on Feb. 11th. Apparently, however, it left something behind. "Comet 45P has lost its tail," reports Bill Williams of the Chiefland Astronomy Village in Florida, who photographed the approaching comet last night:
"The comet still sports a gorgeous green atmosphere ('coma') and is now exiting the dense Ophiuchus Milky Way starfield," says Williams. "The comet sure is moving fast!"