Sky at a Glance | November 2nd, 2007

Some daily events in the changing sky for November 2 – 10.

Weird Comet Holmes is still an easy naked-eye sight. The comet has enlarged from a "star" to a fuzzpatch without losing any of its brightness. It's easy to find in Perseus in the evening sky. This is an extraordinary event not to miss! See our finder charts, full story, and reader photos.

Look before dawn grows too bright!
Watch the dawn Moon pass Regulus, Saturn, and Venus from one morning to the next. (These scenes are drawn for the middle of North America. European observers: move each Moon symbol a quarter of the way toward the one for the previous date. For clarity, the Moon is shown three times actual size.)
Sky & Telescope diagram

Friday, November 2

  • The waning Moon occults (covers) the 1st-magnitude star Regulus before or during dawn — or even in broad daylight — on Saturday morning the 3rd (not "Sunday morning the 3rd"; pardon the mistake in S&T) across the southern and western US, the Caribbean, Mexico, and Central America. The star's disappearance happens on the Moon's bright edge, so you'll need a telescope to watch it even if the event happens in darkness for your location. See the article and maps on page 70 of the November Sky & Telescope.

    Saturday, November 3

  • Daylight saving time ends at 2 a.m. Sunday morning. Now, starry nights will really start coming early. And be sure to make the appropriate change in your local settings for our online almanac (uncheck the Daylight Saving Time box).

    Sunday, November 4

  • The "Red Triangle": Late tonight Mars moves into just the right position, points out reader David Likuski, to form an isosceles triangle with the red giant stars Betelgeuse and Aldebaran. Betelgeuse forms the apex, 21.4° from the other two. The spacing is perfect around 2:30 a.m. Eastern Standard Time.

  • The crescent Moon and Venus shine together in the east-southeast before and during dawn tomorrow morning, as shown above. If you're up early for work, this will be a nice way to start the week!

    Monday, November 5

  • Before and during dawn Tuesday morning, Venus will be just 0.3° or 0.4° from Beta Virginis, which is vastly fainter, magnitude 3.8. That's for the time of dawn in North America. During dawn in Europe the two are at their closest, 0.2° apart. Binoculars will show the star easily. Can you resolve it from Venus's glare with your unaided eyes?

  • The Southern Taurid meteor shower, weak but very long-lasting, should be at its peak this week. Taurids are notably slow-flying, and unlike with most meteor showers, about as many Taurids appear in the evening hours as in the morning. They often make up for their low numbers (roughly five visible per hour) with a high proportion of spectacular fireballs.

    Looking east-southeast in early dawn
    The thinning Moon, now well below Venus, approaches more difficult Mercury and Spica.
    Sky & Telescope diagram
    Tuesday, November 6

  • During early dawn Wednesday morning, the thin waning crescent Moon poses near Mercury and Spica low above the east-southeast horizon, as shown here. Bring binoculars — and don't let dawn get too bright before you look.

    Wednesday, November 7

  • The bright eclipsing variable star Algol (not far from Comet Holmes!) should be in one of its periodic dimmings, magnitude 3.4 instead of its usual 2.1, for a couple hours centered on 10:43 p.m. EST. Algol takes several additional hours to fade and to rebrighten. For all times of Algol's minima this month, good worldwide, see the November Sky & Telescope, page 72.)

    Thursday, November 8

  • Mercury is at greatest elongation, 19° west of the Sun low in the morning sky.

    Friday, November 9

  • New Moon (exact at 6:03 p.m. Eastern Standard Time).

    Saturday, November 10

  • Algol should be at minimum light for a couple hours centered on 7:31 p.m. EST.

    Want to become a better amateur astronomer? Learn your way around the constellations. They're the key to locating everything fainter and deeper to hunt with binoculars or a telescope. For an easy-to-use constellation guide covering the whole evening sky, use the big monthly foldout map in each issue of Sky & Telescope, the essential magazine of astronomy. Or download our free Getting Started in Astronomy booklet (which only has bimonthly maps).

    Once you get a telescope, to put it to good use you'll need a detailed, large-scale sky atlas (set of maps; the standard is Sky Atlas 2000.0) and good deep-sky guidebooks (such as Sky Atlas 2000.0 Companion by Strong and Sinnott, the even more detailed Night Sky Observer's Guide by Kepple and Sanner, or the enchanting though increasingly dated Burnham's Celestial Handbook). Read how to use them effectively.

    More beginners' tips: "How to Start Right in Astronomy".

    This Week's Planet Roundup

    Mercury is low in the sunrise, brightening from magnitude +0.5 to –0.5 this week. Look for it about 45 minutes before sunup just above the east-southeast horizon, very far lower left of bright Venus. Fainter Spica twinkles to Mercury's right.

    To find your local sunrise time (and much else), make sure you've put your location into our online almanac. If you're off daylight saving time, make sure the Daylight Saving Time box is unchecked.

    Venus (magnitude –4.5, in eastern Leo) blazes in the east-southeast before and during dawn. A telescope shows that Venus is about at dichotomy, its half-lit phase.

    Mars on Oct. 31, 2007
    Even the "bland" side of Mars is interesting in this shot from October 31st. The dark horizontal band near bottom is (left to right) Mare Cimmerium, Mare Sirenum, and Mare Australe. Note the two-toned North Polar Hood of clouds at top. The little dark spot just upper right of center is Olympus Mons. Also visible are the other three big Tharsis volcanos — they form a straight diagonal line, lower left to upper right, to the lower right of Olympus Mons. The two on the ends, Ascraeus Mons (upper right) and especially Arsia Mons (lower left), look like 3-dimensional bumps; being near the terminator, their sunnier slopes are on the left. Alternatively, the brightness of their left sides could be due to weak orographic clouds. This has been a controversy; see Sky & Telescope for November 2005, page 66, and February 2006, page 12.


    Sean Walker made this stacked video-frame image with a 12.5-inch reflector, a DMK 21AF04 camera, and RGB filters at 9:58 UT October 31, 2007. Mars was 12.1" wide, and the central-meridian longitude was 140°.

    S&T: Sean Walker
    Mars (magnitude –0.7, in Gemini) now rises as early as 9 p.m. daylight saving time. It shines very high toward the south before dawn — near the zenith, in fact, for mid-northern observers.

    In a telescope, Mars appears 12 or 13 arcseconds in diameter. It will reach 15.9" diameter around its Christmas-season opposition. The Martian dust storms of July and August have abated, and while the planet's atmosphere is still bright and hazy with dust, surface features are showing through better. But they're still low-contrast.

    Jupiter (magnitude –1.9, in southern Ophiuchus) is sinking low in the southwest in twilight. It sets soon after dark.

    Saturn (magnitude +0.8) rises well after midnight and is very high to Venus's upper right before and during dawn. Fainter Regulus (magnitude +1.4) is 7° upper right of Saturn.

    Uranus (magnitude 5.8, in Aquarius) and Neptune (magnitude 7.9, in Capricornus) are well placed in the south early in the evening. Finder charts for them are in the July Sky & Telescope, page 60, and online. With a big scope you can shoot for their faint moons! See the October Sky & Telescope, page 69.

    Uranus
    Uranus, as imaged at high power on August 28th with a 12.5-inch reflector using the stacked-video technique. Visually Uranus appears nowhere near this colorful: pale gray with only a hint of green-blue.
    S&T: Sean Walker
    Pluto is lost in the sunset.

    All descriptions that relate to your horizon or zenith — including the words up, down, right, and left — are written for the world's midnorthern latitudes. Descriptions that also depend on longitude (mainly Moon positions) are for North America. Eastern Daylight Time (EDT) equals Universal Time (UT, UTC, or GMT) minus 4 hours. Eastern Standard Time (EST) is UT minus 5 hours.

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