An opening in the sun’s corona called a coronal hole has been streaming high speed particles Earth’s way this week. They’re expected to arrive later this afternoon, when they’ll pry into the planet’s magnetic defenses and cook up a minor geomagnetic storm. According to the latest space weather forecast, there looks to be a good chance for aurora across the northern states and Canada tonight beginning at nightfall and probably continuing after midnight.
Watch for arcs and small pillars in the lower half of the northern sky. I usually check first at nightfall, then every couple hours till midnight. If we do get aurora, I’ll update this blog with a photo, since clear skies are expected in my region tonight.
Did you try sighting Jupiter and moon with binoculars this morning? It cleared up well after sunrise here, so I grabbed my 10×50 binoculars for a look. At 8:10 a.m. (an hour and 20 minutes past sunrise) I pointed them at the moon and started looking. Nothing at first but seconds later something caught my eye — Jupiter! It was pale against the blue sky, but I had no trouble keeping it in view and even making out the planet’s shape. Unfortunately, it was too late for me to see it with the naked eye.
We have another opportunity for moon-planet sunrise pairs. On March 1 (Friday) the crescent moon shines about 2° to the right (west) of Saturn. This will be challenging to see in binoculars, but I bet some of you will do it. Can you still see the planet 10 minutes before sunrise? At sunrise? Then on Saturday morning (March 2), the moon appears 4° to the right of Venus at sunrise. As long as you can find the thinner moon, Venus will be easy with both binoculars and the naked eye at sunrise and beyond.
NASA recently released the most detailed photo of the object Ultima Thule from the Jan. 1 flyby. This higher resolution view was made when the brings surface features that weren’t as obvious in earlier images like the bright, enigmatic, roughly circular patches of terrain like that big “racetrack” on the larger half. In addition, there are many small, dark pits near the shadowy terminator (the boundary between the sunlit and dark sides of the body) that are more clearly seen than in the last image. Exactly what they are — craters, collapse pits, sublimation pits (where ice has vaporized to create a hole) — we don’t know. Or they could be something new.
The New Horizons spacecraft took the pictures used to make the final, hi-res image from a distance of 4,109 miles (6,628 km). More photos will be coming but this may be the highest resolution we’ll see from the flyby. For more details, click here.