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NightSky™ Sky Calendar
July 2008
New Moon: Wednesday July 2 at 10:19 p.m.
First Quarter: Thursday July 10 at 12:35 a.m.
Full Moon: Friday July 18 at 3:591 a.m.
Last Quarter: Friday July 25 at 2:42 p.m.
OBSERVING HIGHLIGHTS
Mars and Saturn: Pass within 3/4 of a degree of each other on July 11, 2008.

Contribution by Larry Sessions.
Tuesday, July 1
Mars-Regulus, 12:00 a.m.
Closing in on Saturn for a conjunction of less than a degree on July 10, Mars passes less than a degree to the North of Regulus in Leo tonight (Monday night - Tuesday night).
Tuesday, July 1
Mercury at Greatest elongation west, 1:54 p.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-northwest, in Taurus, about an hour before the Sun.
Tuesday, July 1
Moon Perigee 56.37, 4:28 p.m.
As in early June, 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, July 2
New Moon , 10:19 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 July 1.
Friday, July 4
Earth at Aphelion, 3:55 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 bout 94,514,000 miles.
Friday, July 4
Moon-Beehive, 5:00 p.m.
This happens in broad daylight and cannot be directly observed in North America. However, showily 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, July 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, July 9
Jupiter Opposition, 3:36 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.
Thursday, July 10
First Quarter Moon, 12:35 a.m.
As usual, this letter "D" Moon is well up in the South at sunset, and sets about halfway between sunset and sunrise.
Tuesday, July 1
Mars-Regulus, 12:00 a.m.
Closing in on Saturn for a conjunction of less than a degree on July 10, Mars passes less than a degree to the North of Regulus in Leo tonight (Monday night - Tuesday night).
Friday, July 4
Moon-Beehive, 5:00 p.m.
This happens in broad daylight and cannot be directly observed in North America. However, showily 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, July 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, July 9
Jupiter Opposition, 3:36 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.
Tuesday, July 1
Mars-Regulus, 12:00 a.m.
Closing in on Saturn for a conjunction of less than a degree on July 10, Mars passes less than a degree to the North of Regulus in Leo tonight (Monday night - Tuesday night).
Tuesday, July 1
Mercury at Greatest elongation west, 1:54 p.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-northwest, in Taurus, about an hour before the Sun.
Tuesday, July 1
Moon Perigee 56.37, 4:28 p.m.
As in early June, 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, July 2
New Moon , 10:19 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 July 1.
Friday, July 4
Earth at Aphelion, 3:55 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 bout 94,514,000 miles.
Friday, July 4
Moon-Beehive, 5:00 p.m.
This happens in broad daylight and cannot be directly observed in North America. However, showily 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, July 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, July 9
Jupiter Opposition, 3:36 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.
Planets Visible Now
For 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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