Sky at a Glance | June 3rd, 2011

Dusk view
The waxing Moon adorns the western twilight.

Friday, June 3

  • Look west in twilight for the thin waxing crescent Moon far below Pollux and Castor, as shown here.

    Saturday, June 4

  • In twilight, look for Pollux and Castor to the upper right of the Moon, and look for Procyon disappearing about equally far to the Moon's lower left, as shown here.

    Sunday, June 5

  • Well to the right of the Moon as twilight fades are Pollux and Castor. They're lined up to point almost back at the Moon. As soon as the sky grows dark, use binoculars to look for M44, the Beehive Star Cluster, roughly a binocular field above the Moon and perhaps a little to the right.

  • Are you light-polluted where you live? Most of us are. But don't be discouraged by the astronomy you can't do; instead, figure out what you can. For instance, see Hugh Bartlett's "Binocular Sights for City Nights," with finder photos, in the June Sky & Telescope, page 52.

    Monday, June 6

  • Sparkly, summery Scorpius is rearing up in the south-southeast these evenings. Its brightest star is fiery Antares. Look for the other, whiter stars of upper Scorpius on either side of Antares and farther to its upper right.

    Tuesday, June 7

  • A small telescope will always show Titan, Saturn's largest moon. Tonight and tomorrow night Titan is about four ring-lengths to Saturn's west. A 6-inch telescope will begin to show the orange color of its smoggy atmosphere. To identify fainter satellites closer to Saturn, use our Saturn's Moons tracker.

    Wednesday, June 8

  • First-quarter Moon (exact at 10:11 p.m. EDT). The Moon shines south of Leo.

    Dusk view. Twist the panel clockwise for later in the night.
    Watch the thickening Moon march through the gap between Virgo and Corvus night to night.

    Thursday, June 9

  • The waxing Moon passes under Saturn and Porrima this evening and tomorrow evening, as shown here.

    Friday, June 10

  • This evening look for Saturn to the Moon's upper right, Spica to the Moon's upper left, and brighter Arcturus very high above them all.

    Saturday, June 11

  • Around 10 or 11 p.m. (depending on where you live), the dim Little Dipper floats straight upward from Polaris at the end of its handle, like a lost helium balloon trailing its string.

  • With summer almost here, the big Summer Triangle is coming to dominate the eastern sky. Its topmost and brightest star is Vega, plain to see. Look lower left of Vega, by two or three fist-widths at arm's length, for Deneb, the brightest star in its area. Farther to the lower right of Vega is Altair.


    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 sky 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

    Jupiter on June 8, 2011
    Jupiter is coming into better view now low in the dawn, but it's still very far from its best. Christopher Go obtained this fine stacked-video image anyway on June 8th. Jupiter's dark South Equatorial Belt (above center) has fully returned and is very wide. The narrower North Equatorial Belt remains darker red-brown, with even darker barges. At the time of the photo the Great Red Spot had just barely passed the planet's central meridian (where the System II longitude was 163°). The SEB practically encompasses the Red Spot, and the Red Spot Hollow around the spot has changed from white to dark. South is up.

    Mercury is lost in the glow of sunrise.

    Venus (magnitude –3.8) shines very low as dawn grows bright. Look for it low above the east-northeast horizon 20 or 30 minutes before sunrise.

    Mars (vastly fainter at magnitude +1.3) is moving increasingly away to Venus's upper right. Try for it with binoculars.

    Jupiter (magnitude –2.1, at the Aries-Pisces border) rises around the first light of dawn is and well up in good view in the east before dawn becomes too bright. Venus is far to its lower left.

    Saturn (magnitude +0.7, in Virgo) is in excellent evening view high in the south. And just ¼° to its upper right is fainter Porrima (Gamma Virginis), turning Saturn into a naked-eye "double star"! This week Saturn is the closest it will get to Porrima. Shining 15° to their left or lower left is Spica.

    Saturn on May 30, 2011
    Saturn's white activity continues in the planet's northern hemisphere, as seen in this image taken by Christopher Go on May 30th. South is up. This image was created from stacked, selected video frames (taken with an 11-inch scope); don't expect to see this much detail visually!
    Christopher Go

    In a telescope Saturn's rings are 7.3° from edge on, their minimum tilt for more than a decade to come. The rings are casting a relatively wide, prominent black shadow southward onto the globe, and the globe's shadow on the rings is visible just off the globe's celestial east (following) side. The six-months-old white outbreak in the southern hemisphere is still active, as shown here; read more about this huge storm as studied from the Cassini Saturn orbiter and the Very Large Telescope in Chile.

    See how many of Saturn's satellites you can identify in your scope using our Saturn's Moons tracker.

    And don't skip over Porrima — it's a fine, close telescopic binary with equal components and a current separation of 1.7 arcseconds. Use high power and hope for good seeing. See the article in the April Sky & Telescope, page 56.

    Uranus (magnitude 5.9, in western Pisces) is low in the east before the first light of dawn.

    Neptune (magnitude 7.9, in Aquarius) is in the southeast before dawn.

    Pluto (magnitude 14 in Sagittarius) is highest in the south before dawn. A big finder chart for it is in the July Sky & Telescope, page 64.


    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.


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