Venus Has A Fling With The “little King”; Aurora Update

Venus has a remarkably close conjunction with the bright star Regulus Wednesday morning at dawn. Created with Stellarium

Tomorrow morning before dawn if you face east you’ll see a hugely bright planet. That’s Venus. Not as obvious but very close to the planet will shine the star Regulus, the brightest star in Leo and notable for its position at the end of the well-known asterism called the Sickle of Leo. I also like to refer to it as the “backwards question mark.” Regulus means “little king” in Latin and refers to this star’s kingly importance in ancient times.

Venus will be a little less than one degree (two full moon diameters) to the right of Regulus Tuesday, but on Wednesday morning their separation tightens up to a miniscule 0.1 degrees or close enough to make it tricky to split the two with the naked eye. That’s due in part because of their close separation but also because of Venus’ overwhelming brilliance. Binoculars should show them as a beautiful “double star”. Depending on your time zone, the two will be up to a couple tenths of a degree farther apart when they’re up for easy viewing. In Duluth, Minn. 0.2 degrees will separate them at 5:30 a.m. (CDT)

Regulus is some four times the size of the sun and rotates so fast — once every 15.7 hours — that it’s squeezed into a shape resembling an egg. The sun rotates much more slowly — about once every 30 days — and maintains a spherical shape. Credit: adapted from and based on a model by Wenjin Huang. Shape of Regulus is approximate.

By Thursday, their separation will widen again to one degree and keep on spreading. It’s not too surprising that Regulus should get a visit from a planet, since it lies almost exactly on the ecliptic, the path followed across the sky by the sun, moon and planets. Venus has approached even more closely. On July 7, 1959 it occulted or covered up the star for a brief time and will do so again on October 1, 2044. I have my doubts I’ll be around for that rare event, so I hope my younger readers will make an effort to see it.

Those equipped with a small telescope can see Venus and Regulus couple up in the same field of view. Regulus will shimmer like the star it is; Venus will look like a miniature gibbous moon.

Lots of subtle colors were visible to the camera’s eye during the 11:30 p.m. eruption of northern lights. Photo: Bob King

Had there been no moon, last night’s aurora would have been a spectacle. Moonlight washed out its brilliance but the tall rays and movement were still a sight to see. I hope some of you were able to get a peek. The display was unusual in that it appeared in brief, bright eruptions instead of cresting to a peak after a long steady rise. Chances will still be good tonight for a minor display. I’ll post an update this evening.

* UPDATE 9:40 p.m. (CDT) Monday Oct. 1: Very quiet, no auroras at mid-northern latitudes
* UPDATE 11:30 p.m. : Still quiet, no lights

4 Responses

    1. astrobob

      Hi Amanda,
      Very quiet at the moment (6:30 p.m. CDT). If there’s a flare up, I’ll post on the blog, Twitter and FBook.

  1. Edward M. BOll

    We had a nice time in Duluth, October 9-11. A recent report estimated Comet ISON at near Magnitude 17. If this is correct, almost any thing is possible even the potential for a brief moment to hit near Magnitude -20. If this happens, Thanksgiving of 2013, Nov. 28 could look like a day with a Double Sun.

    1. astrobob

      Hi Edward,
      That sounds a bit over the top. I’ve read an analysis of the comet that predicts low negative magnitudes (-1 to -4) or about as bright as Venus. That’s nothing to sniff at either of course. Which report says -17 magnitude? Also keep in mind that one magnitude is 2.5 times brighter than the next. Let’s say ISON does reach -17. That’s about 10 magnitudes or 9,537 times fainter than the sun. Very, very bright but not a second sun.

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