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6 Sky Events this Week: Pinwheel Galaxy Points to Comet, Moon Glides By Neptune

The Pinwheel galaxy near the Big Dipper,  pairs up this week with fading comet PanSTARRS.  Credit: George Jacoby, Bruce Bohannan, Mark Hanna/NOAO/AURA/NSF
The Pinwheel galaxy near the Big Dipper, pairs up this week with fading comet PanSTARRS. Credit: George Jacoby, Bruce Bohannan, Mark Hanna/NOAO/AURA/NSF

Heading towards the end of July, a comet poses for a deep-sky photo op, while planets parade from dusk to dawn, and some shooting stars whet skywatchers appetite.

Venus and the Lion’s Heart.  About a half hour after sunset on Monday, June 22, look for Venus very close to the bright star Regulus—the lead member of the constellation Leo, the lion.  The planet-star duo will be less than 2 degrees apart at dusk, making for a pretty pairing, particularly through binoculars.

Jupiter points to Mars.  Early bird skywatchers facing east about an hour before sunrise can catch Jupiter appearing less than one degree away from fainter Mars—about equal to two full moon disks side-by-side.

Moon meets Neptune.  After nightfall on Wednesday, July 24 look for the waning gibbous moon to point the way to the 8th planet in the solar system. It’s amazing to think that earlier this month astronomers announced the discovery of Neptune’s 14th moon.

The best time to catch the pair will be near midnight as they rise in the southeast sky. For northern hemisphere observers Neptune will be under 5 degrees to the lower right of the moon—less than the width of a fist at arm’s length.

Faint comet pairs with galaxy.  After nightfall on Wednesday, July 24 medium-sized telescope users can get a parting view of comet PanSTARRS gliding by the grand spiral galaxy known as the Pinwheel—or Messier 101—in the Ursa Major constellation. The comet has now faded considerably to 11th magnitude since its close approach back in March, but can still be followed with at least a 6 inch telescope as it heads back to the outer solar system.

Lying face on and appearing as wide as a full moon, M 101 is a bit challenging to find with binoculars because its spiral arms are so diffuse, but is still an easy 8th magnitude oval glow for at least a 4-inch telescope.

Look northwest for a hanging Big Dipper with M 101 just above it’s last two handle stars. The two handle stars and M 101 should form a triangle.

PanSTARRS and the Pinwheel will appear to be only 5 degrees apart—equal to the width of a fist at arm’s length. Their proximity in the sky,however, is just an optical illusion because PanSTARRS lies some 276 million miles (445 million kilometers) from Earth, while the galaxy is a whopping 26 million light years distant.

Look northwest after dark for the Big Dipper, hanging diagonally. Its handle is on the upper left. Follow the curve of the handle on around leftward, for a little more than a Dipper-length, to land on bright Arcturus in the west.

 

Starchart showing the relative positions of the comet PanSTARRS and the Pinwheel galaxy in relation to the Big Dipper. Credit: Starry Night Software/A.Fazekas
Starchart showing the relative positions of comet PanSTARRS and the Pinwheel galaxy in relation to the Big Dipper. Credit: Starry Night Software/A.Fazekas

Mercury and Mars.  Starting at dawn on Saturday, July 27 look towards low east for a faint grouping of three planets that lasts well into the following week. From closest to the horizon-  Mercury, Mars, and Jupiter are best seen at least 30 minutes before sunrise. Binoculars will particularly help track down faint Mercury caught up in the glare of twilight, 7 degrees below the Red Planet.

Minor Meteor Shower Peaks.    Starting late night Sunday, July 28 through July 30, watch for over a dozen shooting stars away from city lights, radiating out from the constellation Aquarius in the low southern horizon. Southern Delta Aquarids is an annual meteor shower that runs from July 12 to August 23 and has a broad activity peak that lasts for 3 nights.  Meteor watchers will have to battle the glare of the waning gibbous moon sharing the early morning sky – when the shower peaks. (Related Meet the Delta Aquarids Meteor Shower)

 

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