Crescent Moon Hangs Over The Hyades Tonight … And More

Watch for the return of the crescent moon tonight, May 6. It will stand about 10° (one fist) 40 minutes after sunset. Stellarium

I’ve been so busy today it only occurred to me now to alert you to a very nice sight in the western sky this evening. A 2-day crescent will shine just above the Hyades star cluster and the star Aldebaran 35 minutes to an hour after sunset. Look low in the west-northwest for the moon, then look below the crescent either naked-eye or better, with binoculars, to see how many of the Hyades you can still see.

On Tuesday night, the moon passes near the planet Mars and very close to Zeta Tauri. Use binoculars to separate star from moon then see if you can spot it without optical aid. Stellarium

The Hyades are a beautiful winter star cluster that’s now so low in the west, this week will be the last to see it before it’s lost in the twilight glow. Meanwhile, the moon moves upward in the coming nights, growing brighter and filling out. Tomorrow night, May 7, it shines a little more than 3° from Mars and a tiny distance south of the star Zeta (ζ) Tauri, the 3rd magnitude star that marks the tip of the western horn of Taurus the bull. Their separation will be only a quarter of a moon-width!

Zeta Tauri is located 440 light years from Earth, so you see the light that left the star around 1579, just two years after the first clock featuring the first minute hand was created by a Swiss clockmaker. Zeta is actually a very close double star. The brighter of the two, Zeta Tau A, is 11 times more massive than the sun and 5-6 times its diameter. The smaller companion star orbits just 1.2 Earth-distances away from this behemoth.

The area between the white lines will see the star Zeta Tauri occulted by the moon Tuesday evening around 9:30 p.m. EDT. Cyan = occultation at moonrise/moonset; red dotted = daytime occultation; blue = twilight occultation. Occult 4

For skywatchers across the southeastern U.S., Central American and Caribbean, the earth-lit side (dark part) of the moon will occult the star Tuesday night. That is, it will pass directly in front of it, blocking the star from view for a time. Occultations are always exciting to watch. Click here for more information including the times (for many cities) when Zeta will disappear behind the dark edge of the moon and reappear along the bright edge as the moon passes by.

From locations along the path edges (white lines) from Georgia to Kansas, observers will see a grazing occultation, with the star flashing in and out of view as it ducks behind mountains and reappears over valleys along the edge of the moon. If you’re in just the right place, grazes are quite the spectacle. More details here.

The times shown at the link at Universal Time. To convert to Eastern Daylight, subtract 4 hours. For Central Daylight, subtract 5 hours. For instance, say you’re watching from Orlando, Fla. You look up Orlando in the list of cities and see the star disappears there at 1:37:24 Universal Time (UT). To convert to Eastern Daylight Time, subtract four hours to get 9:37:24 p.m. If you have any questions on other details, just ask.

Clear skies!

4 Responses

  1. kevan hubbard

    Looks like the Solomon islands will see it too be an exotic destination to view it from!so exotic I don’t think I know anyone who’s ever been to the Solomon islands!

  2. Edward M Boll

    Looking at Mars for the first time in a while at the star party 10 days ago, I was surprised that it was still relatively high in the western sky.

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