Sky at a Glance | June 27th, 2008

Some daily events in the changing sky for June 27 – July 5.

Looking west at dusk
Mars partners up with Regulus on June 30th and July 1st — compare their colors! — as slightly brighter Saturn watches from above left.
Friday, June 27

 

  • This is the time of year when the dim Little Dipper extends straight up from Polaris after dark, like a helium balloon escaped from a summer festival trailing its string as it rises into the night sky.

 

Saturday, June 28

 

  • Late tonight a small telescope, or steadily held binoculars, will show a 5.6-magnitude star just 5 arcminutes south of Jupiter, looking like an out-of-place Jovian moon. Meanwhile Jupiter's moon Callisto, similarly bright, is 10? east of the planet, about as far as it gets.

 

Sunday, June 29

 

  • In the early morning hours of Monday, skywatchers in northeastern North America can watch the thin waning crescent Moon occult (cover and uncover) some of the Pleiades stars. The Moon will be very low in the northeast. The stars will disappear behind the Moon's bright edge (meaning you'll need a telescope) and will reappear from behind the dark edge (meaning binoculars should do). See local timetables (yes, they are for the morning of June 30th).

 

Monday, June 30

 

  • Mars is passing ¾° from Regulus this evening and tomorrow evening, as shown above and at right. Compare their colors!

 

Tuesday, July 1

Look a third of the way from Arcturus to Vega for the dim little semicircle of Corona Borealis, the Northern Crown, with its modestly bright "jewel star," Gemma. Look two thirds of the way from Arcturus to Vega for the dim Keystone of Hercules, with no brighter star at all.

In the Keystone is one of the most familiar deep-sky objects for binoculars: the globular cluster M13. But do you know where to pick up the equally bright globular M92 nearby? For both, see "Binocular Highlight" in the July Sky & Telescope, page 54. Get M92 once, and it'll be there for you forevermore.

Wednesday, July 2

 

  • New Moon (exact at 10:19 p.m. EDT).

 

On the 5th and 6th, with the waxing Moon now on the scene, Mars is midway in its journey from Regulus to Saturn. (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.)
Thursday, July 3

 

  • The red long-period variable star V Bootis should still be about at maximum, 7th or 8th magnitude and spottable in binoculars. It's just 1° from Gamma Bootis; use the comparison-star chart in the May 2007 Sky & Telescope, page 62.

 

Friday, July 4

 

  • Going to watch the fireworks? As you're waiting while dusk deepens, show someone the brightest sky sights. Big Jupiter is rising low in the southeast. The orange-red supergiant Antares sparkles higher in the south. Blue-white Vega is very high in the east, and yellowish Arcturus is very high in the southwest. And of course there's the ongoing Saturn-Mars-Regulus drama low in the western twilight.

 

 

  • Earth is at aphelion today, its furthest point from the Sun for the year (only 1 part in 30 farther than at perihelion in January).

 

Saturday, July 5

 

  • Look for the waxing crescent Moon to the lower right of Saturn, Mars, and Regulus, as shown above.

 

Looking west at dusk
Mars performs its second conjunction on the evening of the 10th, this time with Saturn.

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 standards are Sky Atlas 2000.0 or the smaller Pocket Sky Atlas) 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 classic Burnham's Celestial Handbook). Read how to use them effectively.

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

This Week's Planet Roundup

Looking east-northeast as dawn grows bright
Mercury and Aldebaran glimmer down below the waning crescent Moon on the mornings of June 30th and July 1st. When dawn arrives on the 30th, the Moon has just occulted some of the Pleiades stars for northeastern 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.)
Mercury is very low in the east-northeast in the dawn this week, as shown at right. Don't confuse Mercury with Aldebaran to its upper right, or Capella much farther to its upper left in the northeast. Mercury gets a little higher and brighter as the week progresses.

Venus is hidden in the glare of sunset.

Saturn and Mars (magnitudes +0.8 and +1.6, respectively) continue closing in on each other as they get lower in the west at dusk. Regulus (magnitude +1.4) is involved with them too, as shown in the scenes above.

Jupiter (magnitude –2.7, in Sagittarius) glares low in the southeast at dusk, left of the Sagittarius Teapot. It shines highest in the south around 1 or 2 a.m. daylight saving time. Jupiter will reach opposition on the night of July 8–9.

Uranus and Neptune (magnitudes 6 and 8, respectively, in Aquarius and Capricornus) are high in the southeast and south before the first light of dawn. Use our article and finder charts.

Pluto (magnitude 14.0, in northwestern Sagittarius) is highest in the south around midnight. You'll need a big scope, a dark sky, and a detailed chart.

All descriptions that relate to your horizon or zenith — 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 (UT, UTC, or GMT) minus 4 hours.

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