You are here: Home USNO News, Tours & Events Sky This Week The Sky This Week, 2010 June 22 - 29
The USNO websites,,,,, and are undergoing modernization efforts. The expected completion of the work and return of service is estimated as 30 April 2020. Please submit a requirements form to the USNOPAO if the information you are seeking is not accessible via other means.

The Sky This Week, 2010 June 22 - 29

A Honey Moon and the year's latest sunset
The Honey Moon Rising, 2007
imaged from Shoestring Observatory,
Alexandria, VA, USA

The Moon waxes to her full phase this week, but she hugs the southern horizon as she drifts eastward against the stars.  Full Moon occurs on the 26th at 7:30 am Eastern Daylight Time.  Time Luna undergoes a partial eclipse, with just over 50 percent of her face obscured in the southern half of Earth’s projected shadow.  The event is all but invisible to residents of the eastern U.S., but folks to the west of the Mississippi River can see at least some of the umbral phase.  Residents of coastal California will see the Moon set as the umbral phase ends; only observers in Hawai’i and the Aleutian Islands will see the eclipse in its entirety.  Look for Luna bracketing the bright ruddy star Antares late on the evenings of the 23rd and 24th.  As the week ends she drifts into the more barren starfields of the rising autumnal constellations.

June’s Full Moon is variously known as the Rose Moon, Strawberry Moon, or Honey Moon, all names which infer a warm tint to Luna’s otherwise silvery glow.  Since this Full Moon occurs when Luna is at her most southerly declination, her light is filtered through denser layers of our atmosphere, which in turn is infused with the byproducts of warm weather, haze and humidity.

During the course of this week we experience the end of the summer solstice “season”.  We are now seeing the latest sunsets for the year, with the Sun now sinking below the horizon at 8:38 pm EDT on the evening of the 28th.  As we gradually work our way into July the time will start to inch a little earlier, but most of us probably won’t notice the difference for several weeks.  However, the time of our earliest sunrise occurred back on the 14th, so by the end of this week it will rise five minutes later than it did two weeks ago.

The evening’s planet parade is gradually beginning to tighten up.  As evening twilight begins to deepen, the bright glow of Venus is first to appear.  As the sky darkens, see if you can spot the binocular “Beehive” star cluster just below the dazzling planet on the first few evenings of the new week.  Venus quickly speeds away from the cluster and sets her sights on the bright star Regulus.  She’ll cover half the distance to the star as the week progresses.

Just two weeks ago ruddy Mars passed by Regulus on his own eastward trek.  He’s now got his sights set on Saturn, and by the end of the week he will be halfway between the star and the ringed planet.

Meanwhile, Saturn barely moves against the background stars as Mars and Venus rush headlong in his direction.  There will be a grand gathering of all these planets in another few weeks, which should be a real treat for naked-eye skywatchers.  In the meantime, owners of small telescopes can still delight in the view of Saturn in their instruments.  The planet’s rings are now very gradually opening to our line of sight, but the steeper Sun angle throws a distinctive shadow on the disc itself.  It sounds ironic, but often some of the best “seeing” conditions occur with the stagnant air that warms the nights in summer.  Brave the mosquitoes and have a look!

By the end of the week giant Jupiter rises just before 1:00 am EDT, and since getting up early is gradually becoming easier as sunrise moves later it’s a good time to start looking at the giant planet.  Of all the solar system bodies Jupiter is second only to the Moon in terms if the kind of detail you can see in the small to medium-sized telescope.  This makes watching his ever-changing cloud patterns all the more interesting.  So far this year the usually dark South Equatorial Belt has virtually disappeared, so who knows what other surprises lurk in Old Jove’s turbulent cloud patterns?

USNO Master Clock Time
Javascript must be Enabled