North American Skies

Sky Events / Visible Planets
in association with KMGH Denver's 7
(Times are Mountain (Standard or Daylight as applicable) Time. Add 2 hours for Eastern Time, and 1 hour for Central Time. Subtract 1 hour for Pacific Time.

July 2008

Tuesday, 7/1
Mercury at Greatest elongation west, 11:54 a.m.
Mercury is at its greatest distance to the western side of the Sun, about 22 degrees. Being to the West of the Sun means that it is in the eastern morning sky. It is not particularly well placed, but you might catch it very low in the East-northeast, in Taurus, about an hour before the Sun.

Tuesday, 7/1
Moon at Perigee, 2:28 p.m.
As in early July, the Moon reaches perigee (closest to the Earth) at nearly the same time it is lined up with the Sun as a "New Moon" (tomorrow). This tends to increase its affect on the tides, and so the high tides at this phase may be bigger than usual. This time the Moon is just over 56 Earth radii away, or about 223,400 miles.

Wednesday, 7/2
New Moon , 8:19 p.m.
"New" just signifies that the Moon has started a new cycle, but you can also refer to this as "No" Moon since it is not visible at the time. See 7/1.

Friday, 7/4
Earth at Aphelion, 1:55 a.m.
The Earth's distance from the Sun varies a bit through the year, and it may come as a surprise to some that we are actually farthest in early July, by about one or two percent from the average. Today the Earth is 1.01676 Astronomical Units from the Sun, or about 94,514,000 miles

Friday, 7/4
Moon-Beehive, 3:00 p.m.
This happens in broad daylight and cannot be directly observed in North America. However, shortly after sunset the Moon and the Beehive (M44) star cluster will be close, low in the western sky. From most of North America, the lunar crescent will be slightly to the left of the star cluster. The latter will be particularly difficult to see due to solar glare and nearness to the horizon. Try binoculars.

Sunday, 7/6
Moon-Saturn-Mars, evening
The Moon passes to the left (south) of Mars and Saturn (in Leo) this evening, in the western evening sky.

Wednesday, 7/9
Jupiter Opposition, 1:36 a.m.
Jupiter is at opposition, meaning that it is roughly opposite the Sun in the sky, analogous to the situation with a Full Moon. Thus it rises at about sunset and sets at about sunrise. if you think about the geometry, it is also at its closest to the Earth. These factors combine to make Jupiter its brightest, at about -2.7 magnitude, which is about as bright as it can get. Unfortunately, it is nearly as far South as it can possibly get, so the relative lowness to the horizon cuts the effective brightness.

Wednesday, 7/9
First Quarter Moon, 10:35 p.m.
As usual, this letter "D" Moon is well up in the South at sunset, and sets about halfway between sunset and sunrise.   

Friday, 7/11
Mars-Saturn, 12:27 a.m.
Mars passes about 3/4 of a degree South of Saturn. Unfortunately, this may be after both planets set as seen from many locations, but the view before setting (roughly 11 p.m. local time) is nearly as good. Look low in the West in late evening. Mars is just to the left of brighter Saturn, in Leo.   

Monday, 7/14
Moon-Antares, 6:00 a.m.
Moon passes about a third of a degree South of Antares. This actually occurs after moonset for North American locations, but the Moon is in a close approach to the star shortly after midnight on Monday morning, in the southwest sky. This event occurs as an occultation from parts of Australia, Polynesia, but this is not visible from North America.   

Thursday, 7/17
Moon-Jupiter, 6:23 a.m.
The Moon, nearly Full, passes less than 3 degrees from Jupiter. Unfortunately this is several hours after moonset from most locations. However, the view several hours earlier, to the Southwest, is nearly as good.   

Friday, 7/18
Full Moon, 1:59 a.m.
The Full Moons of Summer mirror the Sun in Winter. In other words, they make short, low tracks across the southern sky. All the various full moons of the year had names given to them by American Indian (First Nations) tribes, as well as by other cultures around the world. According to Kim Long in The Moon Book (Johnson Books, Boulder, 1998), the 7th Full Moon of the year was known as the "Buck Moon" or "Thunder Moon" by the Algonquin; "The Time of Much Ripening" by the Mohawk; and the "The Moon When Everything is Born" by the Tlingit.   

Friday, 7/25
Last Quarter Moon, 12:42 p.m.
"Last" here does not mean that the Moon is gone for good, but merely that it has reached the last major phase in its current cycle. This is also referred to as the "Third" Quarter, when the Moon is 75 percent of the way through the cycle. Last Quarter Moons rise at roughly (very roughly) midnight and set at (again, very roughly) noon the following day.   

Sunday, 7/27
Moon-Pleiades, 10:00 a.m.
The Waning Gibbous Moon passes slightly more than a degree North of the Pleiades. Of course this is midday throughout North America, but look to the eastern heavens shortly before first light.

Monday, 7/28
South Delta Aquarids peak, 2:00 p.m.
This is, as things go, a relatively minor meteor shower. The best time to look is several hours before dawn, toward the southern skies. The radiant, or point from which the meteors seem to radiate, is in the southern part of the constellation Aquarius, but the meteors appear in a wide region of sky. Their paths, if traced backwards, converge at the radiant.   

Tuesday, 7/29
Mercury at superior conjunction, 2:07 p.m.
Superior conjunction means that the planet is in line with the Sun, but on the far side of the Sun. At this moment that planet cannot be seen, but it is important because it marks the moment when the planet moves from the morning sky to the evening sky. However, it likely will not be visible in the evening until at least mid-August.   

Friday, 8/1
New Moon, 4:13 a.m.
As always, New Moons are too near the Sun to be seen. However, sharp-eyed observers may be able to catch a very thin crescent in the western sky after sunset on the day following (Saturday). The second day following (Sunday) should be easier.   

Friday, 8/1
Total Solar eclipse, 4:22 a.m.
Unfortunately this total solar eclipse is not observable at all from most of North America. However, a small portion is visible from far northeastern Canada and northern Greenland. The greatest eclipse is at 6:22 a.m. EDT. The best locations are in Europe and Asia. For details, see the NASA Eclipse web page:  http://eclipse.gsfc.nasa.gov/SEmono/TSE2008/TSE2008.html

Saturday, 8/2
Moon-Venus, 9:00 a.m.
An extremely thin Crescent Moon passes about 2 degrees South of Venus at this time, which unfortunately cannot be seen because of daylight. However, just after sunset, observers with keen eyesight and excellent conditions may be able to catch the fingernail crescent several degrees to the left of pinpoint Venus, very low in the western twilight.

Sunday, 8/3
Moon-Mars, evening twilight
The Crescent Moon passes about 4 degrees below Mars, low in western evening twilight.   

Friday, 8/8
First Quarter Moon, 2:20 p.m.
The Moon was at "Last Quarter" of the previous cycle on 7/25. Since then it has gone through "New Moon" phase, which marked the end of the previous cycle and the beginning of the current cycle. First Quarter, about a week later, means that the Moon has progressed through about 25 percent of its current cycle.

[Data for this calendar has been derived from a number of sources including the Observer’s Handbook 2008 of the Royal Astronomical Society of Canada, Starry Night software, and others. Only events with a reasonable possibility for Northern Hemisphere observers, or those events with some other significance, are given.]




Planets (July 2008)

Mercury
Mercury starts the month with the thin Crescent Moon nearby (a few degrees to the upper left), low in the predawn eastern sky, among the stars of Taurus. At greatest western elongation on the first, it stands some 22 degrees from the Sun, but this distance diminishes (and viewing opportunities worsen) as the month goes on. By midmonth observing is difficult and shortly thereafter impossible, as the planet moves on to superior conjunction behind the Sun on the 29th.

Venus
Venus has been lost in the solar glare since the latter part of May, when it was in the morning eastern sky. But by mid-July it emerges back into the western evening twilight, setting less than an hour after the Sun. Observational opportunities improve through the rest of the year.

Mars
Mars, along with Saturn, is in Leo, sinking into the western evening twilight. It also is slowly getting dimmer as it recedes from Earth, heading for a conjunction on the far side of the Sun in early December. It sets about two hours after the Sun at midmonth. Mars passes less than a degree from Saturn on the evening of the 10th.

Jupiter
Jupiter is the undisputed king of the night. It typically outshines all other planets except Venus and, rarely, Mars. At magnitude -2.7 and no rivals to be seen late at night, Jupiter is a stunning sight, blazing forth in Sagittarius. Look for it low in the southeast in the early evening, to the South late at night, and in the southwest before dawn. At opposition (opposite the Sun in the sky) on the 9th, it rises at sunset and sets at sunrise. A small telescope can provide hours of fascination as the planet's glimmering moons accompany it.

Saturn
Saturn is low in the West at sunset, soon to be lost in the glare of the Sun. At magnitude 0.8, it is roughly twice as bright as nearby Mars (magnitude 1.7), but the lowness in the sky and the twilight glow conspire to make it less than a knockout. Determined observers can still observe the rings, but the ring tilt is steadily decreasing such that it will be edge on -- and perhaps impossible to see -- by early 2009.
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Copyright 2007 Final Copy, Inc. (Limited copying, reposting and/or republication is permitted with credit and a link back to North American Skies.)

Information in this calendar has been calculated and/or derived from a variety of sources. Among them are the yearly Observer's Handbook of the Royal Astronomical Society of Canada; Astronomical Tables of the Sun, Moon, and Planets by Jean Meeus; and Starry Night software by Space.com. Only events with a reasonable possibility for Northern Hemisphere observers, or those events with some other significance, are given.