July Calendar by Dave Mitsky

All times are UT (subtract 4 hours and when appropriate 1 calendar day for EDT). The events listed may not all be visible from Pennsylvania.

7/1 Mars is at its greatest heliocentric latitude
north today; Uranus is 1.3 degree northeast
of the fourth magnitude star Sigma Aquarii
tonight; Mars is at greatest latitude north
(1.8 degrees) of the ecliptic plane at 4:00;
Mercury is 5 degrees south of the first
magnitude star Pollux at 11:00; the Moon is at
perigee, subtending 33'26" from a distance of
357,448 km, at 23:00 - high tides will
result
7/2 Io is 5" north of Europa at 1:03; Full Moon,
known as the Hay or Thunder Moon and
the first of two in July, occurs at 11:09
7/4 Venus is 1.1 degrees north of the first
magnitude star Aldebaran at 10:00; Neptune is
5 degrees north of the Moon at 15:00
7/5 The Earth reaches aphelion at a distance
152,095,300 km from the Sun at 7:00 – this
is 3.4% greater than the perihelion distance
on 1/4; Mars is 0.36 degrees south-southwest
of the center of the open cluster M44 (the
Beehive Cluster), and only a few arcminutes
from its brightest member the sixth magnitude
star Epsilon Cancri, at 8:00
7/6 Uranus is 4 degrees north of the Moon at 3:00;
maximum lunar libration of 9.3 degrees occurs
at 15:00; Comet C/2003 K4 (LINEAR) is nearest
to the Earth at 17:00; a double Galilean
shadow transit by Ganymede and Callisto occurs
from 17:18 to 19:00
7/8 Saturn is in conjunction with the Sun at 17:00;
Mercury travels through the center of M44 at
21:00
7/9 Asteroid 3 Juno (magnitude 9.6) is at
opposition; Last Quarter Moon occurs at 7:34
7/10 Mercury (-0.2 magnitude) is 10' north of Mars
(1.8 magnitude) at 23:00
7/11 The Moon is at the ascending node (longitude
38.7 degrees) at 1:01; asteroid 387 Aquitania
(magnitude 9.8) bisects the third magnitude
binary star Alpha Capricorni at approximately
23:00
7/12 Venus reaches aphelion (0.7282 a.u.) at 8:00;
the Moon is 2.2 degrees south-southeast of the
open cluster M45 (the Pleiades) at 20:00
7/13 Minimum lunar libration of 4.3 degrees occurs at
11:00
7/14 The Moon is at apogee, subtending 29'25" from a
distance of 406,192 km, at 21:00
7/15 Venus reaches its greatest illuminated extent
(297 square arcseconds) today; Venus is at
greatest brilliancy (-4.5 magnitude) at 1:00;
Callisto is in eclipse from 2:17 to 4:26;
Comet 42P Neujmin reaches perihelion at 21:00
7/16 Comet 29P Schwassmann-Wachmann 1 reaches
perihelion at 18:00; the Moon is 5
degrees north of Saturn at 20:00
7/17 The Moon is 1.8 degrees south-southwest of the
first magnitude star Pollux at 7:00;
New Moon (lunation 1009) occurs at 11:24
7/18 The Moon is 3.4 degrees north-northeast of M44
at 11:00
7/19 Mars is 4 degrees south of the Moon at 2:00;
Mercury is 5 degrees south of the Moon at
15:00; the Moon is 1.7 degrees north-northeast
of asteroid 6 Hebe at 22:00
7/20 The Moon is 4.2 degrees north-northeast of the
first magnitude star Regulus at 8:00; the Sun
enters the constellation of Cancer (longitude
118.05 degrees) at 11:00; maximum lunar
libration of 7.9 degrees occurs at 12:00;
Mercury is at the descending node at 20:00
7/21 Jupiter is 3 degrees south of the Moon at 13:00
7/23 A double Galilean satellite transit by Io and
Callisto begins at 2:11
7/24 The Moon is 3.2 degrees north-northeast of the
first magnitude star Spica at 13:00
7/25 First Quarter Moon occurs at 3:37
7/26 Mercury (0.4 magnitude) is 1.5 degrees south of
Regulus (1.4 magnitude) at 0:00; the Moon is
at the descending node (longitude 217.0
degrees) at 11:29; the equation of time
equals -6.51 minutes at 21:00
7/27 Mercury reaches its greatest illuminated extent
(22 square arcseconds) this evening; Mercury
is at greatest eastern elongation (27.1
degrees) at 3:00; the peak of the southern
Delta Aquarid meteor shower (~20/hour) occurs
at 19:00; the Moon is 1.8 degrees north-
northeast of the first magnitude star Antares
at 20:00; minimum lunar libration of 5.2
degrees occurs at 22:00
7/28 Comet C/2003 K4 (LINEAR) passes within 15' of
the globular cluster NGC 5466 this evening
7/30 The Moon is at perigee, subtending 33'10" from a
distance of 360,324 km, at 6:00
7/31 Neptune is 0.5 degree north of the fourth
magnitude star Theta Capricorni tonight;
Mercury reaches aphelion (0.4667 a.u.) at
4:00; Full Moon, a so-called Blue Moon,
occurs at 18:05

Times and dates for the lunar light rays predicted to occur this month are available at http://www.lunar-occultations.com/rlo/rays/rays.htm

Mercury begins a lackluster apparition for northern observers this month. Its maximum altitude at sunset for our latitude of 40 degrees north occurs on July 16, well before the date of Mercury's greatest eastern elongation.

As it travels through Taurus and pulls away from the Earth, Venus increases in phase as it decreases in apparent size. Its size and phase are 29" and 39% respectively on July 31 when Venus is about 3 degrees south of the supernova remnant M1.

The closest conjunction of two planets for this year occurs on July 10 when Mars and Mercury are only 0.2 degree apart. By the end of July, 1.8 magnitude Mars sets only 50 minutes after the Sun.

Located in southern Leo, Jupiter still shines brightly at slightly less than –2.0 magnitude. At month's end the planet sets less than two hours after sunset.

Saturn is lost in the glare of the Sun until late in July when it can be seen in the east-northeastern morning sky.

Uranus draws increasingly nearer to Sigma Aquarii during July. At the end of the month the 5.7 magnitude planet lies 0.6 degree north of this star.

During July Neptune, shining at 7.8 magnitude, also has a close approach to a star as it travels westward a half degree towards Theta Capricorni. Neptune is 30' north of Theta on July 31.

Pluto is fairly high in the south in southwestern Serpens Cauda this month.

On the night of July 20 Comet C/2001 Q4 (NEAT) is situated between Alpha and Beta Ursae Majoris.

In July Comet C/2003 K4 (LINEAR) heads southwestward from Hercules into Bootes.

Asteroids 4 Vesta and 9 Metis, shining at seventh and tenth magnitude respectively, are within 30' of each other in the constellation of Aquarius for a period of 3 weeks this month.

Forty binary and multiple stars for July: Eta Draconis, 17 & 16 Draconis, Mu Draconis, Struve 2273, Nu-1 & Nu-2 Draconis, Psi Draconis (Draco); Kappa Herculis, Gamma Herulis, Struve 2063, 56 Herculis, Struve 2120, Alpha Herculis (Ras Algethi), Delta Herculis, Rho Herculis, Mu Herculis (Hercules); Rho Ophiuchi, Lambda Ophiuchi, 36 Ophiuchi, Omicron Ophiuchi, Burnham 126 (ADS 10405), Struve 2166, 53 Ophiuchi, 61 Ophiuchi (Ophiuchus); h5003 (Sagittarius); Xi Scorpii, Struve 1999, Beta Scorpii, Nu Scorpii, 12 Scorpii, Sigma Scorpii, Alpha Scorpii (Antares), h4926 (Scorpius); Struve 2007, 49 Serpentis, Struve 2031 (Serpens Caput); 53 Serpentis, Struve 2204, h4995, h2814 (Serpens Cauda); Epsilon Ursae Minoris (Ursa Minor)

Challenge binary star for July: 24 Ophiuchi

Sixty-five deep-sky objects for July: NGC 6140, NGC 6236, NGC 6340, NGC 6395, NGC 6412, NGC 6503, NGC 6543 (Draco); IC 4593, M13, M92, NGC 6106, NGC 6166, NGC 6173, NGC 6181, NGC 6207, NGC 6210, NGC 6229, NGC 6482 (Hercules); B61, B62, B63, B64, B72, IC 4634, IC 4665, LDN 42, LDN 1773, M9, M10, M12, M14, M19, M62, M107, NGC 6284, NGC 6287, NGC 6293, NGC 6304, NGC 6309, NGC 6356, NGC 6366, NGC 6369, NGC 6384, NGC 6401, Tr 26 (Ophiuchus); NGC 6440, NGC 6445 (Sagittarius); B50, B55, B56, Cr 316, M4, M6, M7, M80, NGC 6144, NGC 6153, NGC 6192, NGC 6231, NGC 6242, NGC 6302, NGC 6337, NGC 6451 (Scorpius); NGC 6217, NGC 6324 (Ursa Minor)

Challenge deep-sky object for July: NGC 6380

__________________
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Never attribute to malice that which can be adequately explained by stupidity.

This is a great list Dave, thanks!

__________________
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Publisher
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Groovy Thanks Dave!

__________________
"The stars are my home"
"I've seen things you people wouldn't believe... Attack ships on fire off the shoulder of Orion... I've watched c-beams glitter in the dark, near the Tanhauser Gate... all those moments will be lost, in time... like tears in the rain..."