August Skies 2005

Introduction:
Summer rapidly winds down during the month of August. Each day is a bit shorter and each night a bit longer as we approach Autumn. However, Summer’s spectacular stars and constellations remain visible most of the night, and the Milky Way presents excellent opportunities for stargazing with binoculars and small telescopes.

August is the month for the Perseid meteor shower, the most accessible of the year. Very small pieces of debris from an old comet impact the Earth’s upper atmosphere between August 9th and 13th, making a spectacular sight for naked-eye observers under a dark sky. (SEE MORE BELOW!)

Mars continues to brighten, rise earlier each night, and move higher in the night sky. At magnitude –0.5, Mars is already the 4th brightest object in the night sky, only outshone by the Moon, Venus and Jupiter.

The Sun: The SUN begins August in the constellation of CANCER. It moves into LEO on August 10th and spends the rest of the month moving across the Zodiac lion.

The Moon:
August’s NEW MOON occurs the evening of the 4th in Cancer.
The 1st QUARTER MOON is seen on August 12th in LIBRA.
August’s FULL MOON occurs about midday on August 19th in AQUARIUS, and we will see it rise about ½ hour after sunset that evening.
The 3rd QUARTER Moon occurs on August 26th in Taurus.

In August the Moon passes near four naked-eye planets:
VENUS: Low in the West the evening of August 7th in LEO.
JUPITER: Overnight the 9th-10th in VIRGO.
MARS: Overnight the 24th-25th in ARIES.
SATURN: Near a thin crescent Moon before dawn on the 31st.

The Moon also passes near these prominent stars:
Crescent Moon is near Castor & Pollux in GEMINI the morning of the 3rd.
Crescent Moon is close to Spica in VIRGO the evening of the 10th.
Near Antares in SCORPIO overnight the 13th-14th.
Last Quarter Moon near the Pleiades star cluster in TAURUS the morning of the 26th.

The Evening Sky:
Early August sunsets occur at about 7:20p.m., but the Sun will set noticeably earlier, at 6:05p.m., at month end.

Evening Planets. Venus, Jupiter, and now Mars.
VENUS remains the brightest object in the night sky, after the Moon. Venus begins the month in LEO and moves eastward into VIRGO on August 11th. Look for brilliant white Venus in the Western sky after sunset. Through a telescope, Venus displays phases like the Moon. It begins August in a nearly-Full phase, and continues to wane like the Moon does after it is full.

Venus moves Southward during August, making an ever shallower angle to the horizon. Although Venus will not move much higher in the sky during August, it will not become any more difficult to observe.

JUPITER, the 2nd brightest nighttime object after the Moon and Venus, remains in VIRGO all month. Jupiter is fast approaching the Sun in the Western sky after dark; it sets about 9:25p.m. on the 1st, but about 8:40p.m. on the 31st.

Watch for Venus to close the distance to Jupiter during August. They will end the month quite close together in the sky. Jupiter can be distinguished by its faintly yellow-white color, by contrast to Venus’ pure white hue. Through binoculars or a telescope, Jupiter’s four largest satellites will be visible along the planet’s equator.

MARS is visible most of the night, and is technically an Evening Planet since it now rises before midnight. Mars begins August in PISCES, moves into CETUS on the 3rd, then on into ARIES on August 7th, where it remains the rest of the month. The Red Planet is now very bright and the third brightest night sky object after the Moon, Venus and Jupiter. Mars rises about 11:25p.m. on August 1st and nearly an hour and a half hour earlier (10:05p.m.) on the 31st.

As Earth continues to approach slower Mars in their orbits around the Sun, when viewed in a telescope Mars grows larger in size. It will be closest to the Earth (largest and brightest) in late October.

What Else to See?
Look for the 3 day old Crescent Moon directly to the right (North) of Venus after sunset on August 7th. Through binoculars or a small telescope, find the 4th magnitude star Sigma Leonis above the Moon’s dark Eastern edge. Observers in California will see the Moon occult (or eclipse) this star shortly after sunset Arizona time.

Early meteors from the Perseid meteor shower may be seen the evenings of August 9th through the 13th, although meteor watching is better in the early morning hours, when Perseus is highest in the sky. Though the crescent Moon brightens the evening sky, it will NOT interfere with meteor watching after midnight, when the greatest number of meteors can be seen.

In early evening, look to the Northeast sky (anywhere between the horizon and directly overhead). Later, as Perseus rises higher, meteors may appear in all directions, “shooting” away from Perseus.

August is still an excellent month to view star clusters and nebular clouds in the Milky Way. Look to the South starting with zodiac constellations SCORPIO and SAGITTARIUS. (Note Scorpio’s curved tail and stinger.) Just left of the stinger stars are 2 compact star clusters, #6 & #7 in Messier’s famous catalog. Above these, along the Milky, even a small pair of binoculars will reveal a half dozen more fuzzy star clouds in the constellations of OPHIUCHUS, SCUTUM, DELPHINUS, AND AQUILA.

Back to Scorpio: In the scorpion’s heart is found the red Supergiant star ANTARES. Just a Moon’s diameter to the right of Antares is Messier object “M4”, a large “Globular Cluster” with over 100,000 stars packed into an area of the sky about the size of the Full Moon. It is fuzzy in binoculars, but a telescope of 6-inches diameter or larger will show dozens of individual pinpoint stars.

An hour later, CYGNUS (AKA the Northern Cross) and LYRA the lyre will be nearly overhead. The three brightest stars overhead are called the “Summer Triangle” (VEGA in Lyra & highest overhead, DENEB in Cygnus lower to the East, and ALTAIR, in Aquila to the Southeast).

As the Moon slowly moves from West to East around the Earth each month, it occasionally occults (or eclipses) background stars. A list of occultations of stars of 6th magnitude or brighter is posted < ahref=”http://www.evliving.com/astron.php?action=fullnews&showcomments=1&id=3548″>here.

The Morning Sky
Sunrise on August 1st is at 5:45a.m. Each morning afterward the Sun rises a bit later. August 31st’s sunrise occurs at 6:05a.m.

Look for the crescent MOON mornings through the 3rd and again from the 21st through the end of the month. The Moon is near MARS on the morning of August29th, when both rise at about 12:30a.m.

Morning Planets: Mercury and Saturn.
SATURN starts the month too close to the Sun to be seen. However, it rapidly moves Westward away from the Sun, rising earlier each day. On the 15th, Saturn rises in a dark sky. Each day afterward Saturn only becomes easier to see, shining brightly in otherwise nondescript CANCER the zodiac crab.

Mercury races past the Sun on August 7th again becoming a Morning Planet. Look for Mercury first between the 15th and the 20th of August, when it rises a bit North of East and stands directly below Saturn. Mercury chases, but does not catch up with Saturn, but both will be easy to spot through the end of the month as yellow-orange Mercury draws near yellow Saturn. Late in the month, Mercury again reverses direction and heads back toward the Sun.

What Else to See? The Summer Milky Way is easy to see after midnight, as it reaches high overhead. It is also cooler in the wee hours, so morning observers are more comfortable in August. Binoculars or a small telescope will help you pick out many star clusters, star clouds and gas clouds (nebulae) by sweeping along the arc of the Milky Way from Cassiopeia in the Northeast to Sagittarius in the Southwest. (Note the online star chart below.)

The Moon will either occult or approach very close to several stars of 6th magnitude or brighter during August mornings. Specific times for these events are given here.

Good Luck Observing!