Sky at a Glance | November 5th, 2010

By: Alan MacRobert November 5, 2010 0

Friday, November 5

This is the time of year when the Big Dipper lies low horizontally, "holding water," during early evening. Look for it just above your north-northwest horizon. How low it appears — or whether you can see it at all! — depends on your latitude. The farther north you are, the higher it'll be.

Rolando Ligustri photographed 103P/Comet Hartley 2 on September 6th. Since then the round coma has grown larger, but the central condensation remains weak.

Rolando Ligustri

Periodic Comet Hartley 2 is fading now that it's drawing farther away from both Earth and Sun. It's currently 6th or 7th magnitude and diffuse; its apparent magnitude depends a lot on the darkness of your sky and the nature of your observing instrument. The time to look for it is just before the first light of dawn at your location. See our article and finder charts: Encounters with Comet Hartley 2. This is the comet with the weird nucleus that NASA's EPOXI mission just flew past!

Saturday, November 6

Mira, the brightest long-period red variable star, is just starting to fade from its unusually bright maximum. As of November 4th observers were still reporting it at about magnitude 3.2, obvious to the unaided eye. Mira is up in good view in the east-southeast by 8 or 9 p.m. daylight saving time. Estimate its brightness using the comparison-star chart in the September Sky & Telescope, page 58.

New Moon (exact at 12:52 a.m. on this date Eastern Daylight Time).

Sunday, November 7

For most of North America, daylight saving time ends at 2 a.m. Sunday morning. Clocks "fall back" an hour.

Use binoculars to look for this challenging group of objects soon after sunset on the 7th and 8th. (This scene is 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

A twilight challenge: about 20 minutes after your local sunset time, use binoculars to scan for Antares and Mars flanking the thin crescent Moon very low in the southwest, as shown here. (When using our online almanac, be sure the Daylight Saving Time box is unchecked now.)

Monday, November 8

These evenings, look upper left of bright Jupiter for the Great Square of Pegasus, and farther to Jupiter's lower right for Fomalhaut.

Jupiter's moon Io reappears out of eclipse, just off the planet's eastern limb, around 10:09 p.m. EST. Then, Europa reappears out of eclipse right next to Io at 11:19 p.m. EST. Each takes a minute or two to swell to its full brightness. (For a listing of all of Jupiter's satellite events this month, good worldwide, see the November Sky & Telescope, page 58.)

Tuesday, November 9

If you have a 10-inch or larger telescope, have you ever tried for the major moons of Uranus and Neptune? They're not easy. See the guide in the November Sky & Telescope, page 56.

Wednesday, November 10

Yes, it's possible to see the "summer" Teapot of Sagittarius in November. This evening the Moon guides your way. Find a spot with a good view of the southwest horizon, and right as twilight ends, look below the Moon for the Teapot tilting way down. It's about the size of your fist held at arm's length.

Thursday, November 11

Using binoculars or a telescope, have you ever found the little star cluster M29 near the center of the Northern Cross? See Gary Seronik's Binocular highlight article in the November Sky & Telescope, page 45.

Friday, November 12

Algol, the brightest eclipsing variable star, is at its minimum light (magnitude 3.4 instead of its usual 2.1) for a couple hours centered on 9:52 p.m. PST (12:52 a.m. on the morning of the 13th EST).

Saturday, November 13

First-quarter Moon (exact at 11:39 a.m. EST). The Moon forms a nearly equilateral triangle with Jupiter to its left and fainter Fomalhaut below them both.

Sky at a Glance is now an iPhone app! Put S&T SkyWeek on your iPhone, iPad, or iPod Touch and get the above listings anytime, anywhere — with interactive sky maps! Tap a button to see the scene described, customized for your location worldwide. From there you can scroll the view all around the sky, zoom in or out, change to any time or date, and turn on animation. Go to Apple's iTunes store from your device and buy S&T SkyWeek — just 99 cents!

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 map in the center of each issue of Sky & Telescope, the essential magazine of astronomy. Or download our free Getting Started in Astronomy booklet (which only has bimonthly maps).

Sky Atlas 2000.0 (the color Deluxe Edition is shown here) plots 81,312 stars to magnitude 8.5. That includes most of the stars that you can see in a good finderscope, and typically one or two stars that will fall within a 50× telescope's field of view wherever you point. About 2,700 deep-sky objects to hunt are plotted among the stars.

Alan MacRobert

Once you get a telescope, to put it to good use you must have a detailed, large-scale sky atlas (set of charts). The standards are the Pocket Sky Atlas, which shows stars to magnitude 7.6; the larger Sky Atlas 2000.0 (stars to magnitude 8.5); and the even larger and deeper Uranometria 2000.0 (stars to magnitude 9.75). And read how to use your charts effectively.

You'll also want a good deep-sky guidebook, such as Sky Atlas 2000.0 Companion by Strong and Sinnott, or the more detailed and descriptive Night Sky Observer's Guide by Kepple and Sanner, or the classic if dated Burnham's Celestial Handbook.

Can a computerized telescope take their place? I don't think so — not for beginners, anyway, and especially not on mounts that are less than top-quality mechanically. As Terence Dickinson and Alan Dyer say in their Backyard Astronomer's Guide, "A full appreciation of the universe cannot come without developing the skills to find things in the sky and understanding how the sky works. This knowledge comes only by spending time under the stars with star maps in hand."

This Week's Planet Roundup

Mercury is hidden in the glare of the Sun.

Venus, magnitude –4.5, is rapidly emerging into view in the eastern dawn. Look for it low in the east-southeast as dawn begins to brighten. Above Venus are much fainter Spica and, higher up, Saturn.

Mars, magnitude +1.4, is disappearing deep in the sunset.

A new bright white spot (indicated) has appeared in the latitude of Jupiter 's South Equatorial Belt, likely marking the start of the belt's return. If history is a guide, the storm responsible for the white spot will start dredging up dark material from below, which will spread around Jupiter at this latitude. Read our article Jupiter's Lost Belt Reviving?, and keep watch for yourself! Christopher Go took this image at 10:24 UT November 10th. South is up.

Christopher Go

Jupiter (magnitude –2.7, at the Pisces-Aquarius border) shines high in the southeast to south during evening. It's by far the brightest starlike point in the sky. In a telescope it's still a big 46 arcseconds wide.

Jupiter's Great Red Spot is near System II longitude 157°. Assuming it stays there, here's a list to print out of all the Great Red Spot's predicted transit times for the rest of this observing season.

Saturn (magnitude +0.9, in Virgo) glows in the east-southeast in early dawn, above bright Venus and dim Spica. The best time to try observing Saturn with a telescope is in morning twilight, perhaps an hour before your local sunrise time, when the planet will be less blurred by the low-altitude atmospheric mess. Saturn's rings have widened to 8° from edge-on.

Uranus (magnitude 5.8) is 3° east of Jupiter.

Neptune (magnitude 7.9, in Capricornus) is highest in the south after dusk. See our finder charts for Uranus and Neptune online or, with article, in the September Sky & Telescope, page 56. Can you see any color in Uranus and/or Neptune?

Pluto (magnitude 14.0, in Sagittarius) is disappearing in the southwest after dark.

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

To be sure to get the current Sky at a Glance, bookmark this URL:
http://SkyandTelescope.com/observing/ataglance?1=1

If pictures fail to load, refresh the page. If they still fail to load, change the 1 at the end of the URL to any other character and try again.

About Alan MacRobert

Alan M. MacRobert became an avid Sky & Telescope subscriber in 1966 at age 14, joined the editorial staff in 1982, and is now a senior contributing editor, semi-retired. He played a role in practically every part of the magazine and the company's other products for more than a generation, both on the amateur-observing side and the science-reporting side. In 1994 a book collection of his observing how-tos and telescopic sky tours was published as Star Hopping for Backyard Astronomers. He has produced This Week's Sky at a Glance online every week since 1989.