Chance For Aurora Tonight / More Daylight Planets / Best Ultima Thule Yet

That big black thing is a coronal hole, a large “opening” in the sun’s corona where particles from the sun can stream freely out into space. Coronal holes can sometimes spark auroral displays. The photo was taken on Feb. 25. NASA/SDO

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.

The moon and the pale planet Jupiter are visible in this photo taken with a 500mm lens this morning at 8:10 a.m. CST from Duluth, Minn. Bob King

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.

The moon continues making visits to the planets over the next few mornings. Stellarium
These binocular views show the close approaches of the moon to Saturn and Venus later this week. Positions and times are for the Midwest. For East Coast observers, the moon will a little farther to the right; for the West Coast, it will be further left and closer to both planets. Stellarium

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.

The most detailed images of Ultima Thule, obtained just minutes before the spacecraft’s closest approach at 12:33 a.m. EST on Jan. 1, have a resolution of about 110 feet (33 meters) per pixel. Nine individual photos went into making this picture. Click it for the highest resolution version. NASA/JHAPL/SRI, NOAO

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.

6 Responses

  1. Edward M Boll

    Yes, what a view! It was so cloudy lately. That I lost track of the Moon and it surprised me. It was so cloudy and cold this month that I never really got a view of Iwamoto, now about magnitude 8. But all hope is not gone yet. I would like to get another view of Wirtanen but time for it is just about over from my perspective, certainly not what it was a couple month ago.

  2. kevan hubbard

    I’m in a fairly light polluted village at the moment (chemical plants to the south, lots of them!)so won’t be able to see any northern lights however I have seen Mercury three nights in a row.we have a high pressure moved in over England sending temperatures up to nearly 20 c.. I’ve never know such warm weather in february.one thing I have been hoping to see is polar stratospheric clouds aka nacreous clouds sort of the winter equivalent of nocullient clouds,well they’re much lower than nocullient clouds but much higher than normal clouds and probably form via a similar but little understud mechanism, but no luck.

    1. astrobob

      Kevan,
      I’d love to see nacreous clouds. They’re on my list along with sprites. I’ve seen noctilucent clouds on about a half-dozen occasions. Sorry to hear about your light pollution. Good going on Mercury!

  3. Gary Johnson

    So you may have covered this already. The movement of the magnetic pole has been in the news. How will that affect aurora, if at all? Assuming, of course, that it continues to move further away.

    1. astrobob

      Gary,
      I’ve not heard of or seen any changes in the aurora caused by the migrating pole in my lifetime. I’ve read that if the field flips, there will be a time when the magnetic field is weaker than normal, in which case auroras would be seen at more southerly latitudes.

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