SkyandTelescope.com - This Week's Sky at a Glance

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This Week's Sky at a Glance
Some daily events in the changing sky for July 30 – August 8.
by Alan M. MacRobert
Some daily events in the changing sky for August 6 – 14.
Venus continues as the bright landmark for shy Mars and Saturn after sunset.
Sky & Telescope diagram
Friday, Aug. 6 Starting this evening, Mars andSaturn spend more than a week sliding above brilliant Venus low in thewest as twilight fades.
Have you seen any earlyPerseid meteors yet? The peak of the shower is expected to arrive nextThursday night (the night of August 12-13), so start planning now! Seeour articleDark Nights for the Perseids.
Saturday, Aug. 7
Venus, Mars, and Saturnare gathered their most tightly this evening, fitting in a circle 4.8°in diameter — just small enough to qualify as a "planetary trio" (agrouping within a 5° circle).
Sunday, August 8
Keep watching theVenus-Saturn-Mars triangle as it changes shape day by day in the westerntwilight. Spica too is now moving in on the scene from the left, asshown above. Can you also make out Gamma (γ) Virginis, magnitude 2.7?For this you'll probably need binoculars.
Monday, August 9
New Moon (exact at 11:08 p.m. Eastern Daylight Time).
Tuesday, August 10
Bright Vega crossesnearest your zenith around 10 or 11 p.m. daylight-saving time (dependingon how far east or west you live in your time zone). When you see Veganearest the zenith, that means the Teapot of Sagittarius is at itshighest in the south.
The Sagittarius Teapot has noless than eight globular clusters around its spout. Make it a project toferret them out with your scope, using Sue French's Deep-Sky Wonderscolumn and chart in the AugustSky & Telescope, page 64.
Wednesday, August 11
The thin crescent Moon is a few degrees lower left of Mercury, extremely low in the west 15 to 30 minutes aftersunset as shown below. This is a lovely but difficult observation, even with binoculars.
The Perseid meteor shower will be very active late tonight. SeeDark Nights for the Perseids.
Thewaxing Moon joins the changing planet scene late in the week. (Thevisibility of the fainter objects in bright twilight is exaggeratedhere. These scenes are drawn for the middle of North America; Europeanobservers should move each Moon symbol a quarter of the way toward theone for the previous date. In the Far East, move it halfway.)
Sky & Telescope diagram
Thursday, August 12
In twilight, look for the waxing crescent Moon about 7° below the Venus-Saturn-Mars triplet very low in the west.
In that planetary triplet, Mars remains within 3° of Venus from now through the 25th.
The Perseid meteors should be at their peak late tonight. SeeDark Nights for the Perseids.
Friday, August 13
Low in the west in twilight, the crescent Moon is about 10° left of Venus, as shown above.
Saturday, August 14
Arcturus is thebrightest star high in the west after dusk (high above the place whereVenus declines and sets). At about the same height to its right in thenorthwest, look for the Big Dipper now turning right-side up. Nearly ashigh in the northeast, W-shaped Cassiopeia is climbing upward.