Sky and Telescope - August 2015 - 44

OBSERVING

Planetary Almanac
Mercury

Sun and Planets, August 2015
August

Sun

Venus

Mercury

Venus
1
16

31

Mars

Mars
16

1

31

Jupiter
Jupiter

16

Saturn

16

Neptune
Pluto

+30°
+20°

GEMINI

Pollux

Pleiades

Mars
10
TA U R U S

+10°
0°

Venus

-40°

7

8 am

31′ 31″

-

1.015

+8° 55′

-

-26.8

31′ 41″

-

1.010

9h 20.6m

+17° 21′

9° Ev

-1.2

5.1″

95%

1.330

11

10h 30.1m

+10° 32′

18° Ev

-0.4

5.4″

84%

1.254

21

11h 26.1m

+3° 25′

23° Ev

-0.1

5.9″

73%

1.142

31

12h

11.0m

-3° 05′

27° Ev

+0.1

6.7″

61%

1.008

1

9h 59.8m

+6° 41′

22° Ev

-4.4

52.1″

7%

0.320

11

9h 40.7m

+6° 16′

10° Ev

-4.1

57.1″

2%

0.292

21

9h 16.6m

+7° 16′

12° Mo

-4.1

57.1″

2%

0.292

31

9h

00.6m

+8° 55′

23° Mo

-4.5

52.2″

8%

0.320

1

7h 46.8m

+22° 09′

14° Mo

+1.7

3.6″

99%

2.575

16

8h 27.7m

+20° 12′

18° Mo

+1.7

3.7″

99%

2.551

31

9h 07.0m

31
1

+17° 44′

23° Mo

+1.8

3.7″

98%

2.513

00.2m

+13° 08′

19° Ev

-1.7

31.1″

100%

6.329

31

10h 25.0m

+10° 51′

3° Mo

-1.7

30.8″

100%

6.397

1

15h 45.1m

-17° 48′

110° Ev

+0.4

17.3″

100%

9.600

31

15h 47.7m

10h

1h

-18° 03′

82° Ev

+0.5

16.5″

100%

10.090

15.3m

+7° 15′

123° Mo

+5.8

3.6″

100%

19.425

16

22h 42.2m

-9° 05′

164° Mo

+7.8

2.4″

100%

28.988

Pluto

16

18h 56.3m

-20° 54′

140° Ev

+14.1

0.1″

100%

32.141

22h

20 h

16h

18h

E Q U AT O R

Arcturus

HERCULES
A Q U ILA

Uranus

25

C A PRIC O RN U S

ECLI

+10°

CORVUS

Saturn

Fomalhaut

Midnight

0°

19

22

PTIC

SAGITTARIUS
10 pm

+20°

Jupiter
Mercury

LIBRA

Pluto

LOCAL TIME OF TRANSIT
2 am
6 am
4 am

LEO

VIRGO

OPHIUCHUS

Neptune

10 h
+30°

A Q U A RIU S

Aug 29 -30
CETUS

12h

14 h
BOÖTES

CYGNUS
PEGASUS
PISCES

Rigel

CANIS
MAJOR
10 am

-26.8

35.2m

ARIES

ERID ANU S

-30°

-

10h

Neptune

Aug 4

Sirius

-20°

+18° 12′

1

Vega

Betelgeuse
ORION

Distance

16

0h

Procyon

-10°

Illumination

Uranus

2h
4h
RIGHT ASCENSION

6h

Diameter

Planet disks at left have south up, to match the view in many telescopes. Blue ticks indicate the pole currently tilted
toward Earth.

10"

8h

Magnitude

42.7m

The table above gives each object's right ascension and declination (equinox 2000.0) at 0 h Universal Time on selected dates,
and its elongation from the Sun in the morning (Mo) or evening (Ev) sky. Next are the visual magnitude and equatorial
diameter. (Saturn's ring extent is 2.27 times its equatorial diameter.) Last are the percentage of a planet's disk illuminated
by the Sun and the distance from Earth in astronomical units. (Based on the mean Earth-Sun distance, 1 a.u.
is 149,597,871 kilometers, or 92,955,807 international miles.) For other dates, see SkyandTelescope.com/almanac.

Uranus

Castor

Elongation

8h

1

Saturn

+40°

Right Ascension Declination

31

21

11

H Y D R A

SCORPIUS
8 pm

6 pm

4 pm

2 pm

DECLINATION

Aug 1

-10°
-20°
-30°
-40°

The Sun and planets are positioned for mid-August; the colored arrows show the motion of each during the month. The Moon is plotted for evening dates in the Americas when it's waxing (right
side illuminated) or full, and for morning dates when it's waning (left side). "Local time of transit" tells when (in Local Mean Time) objects cross the meridian - that is, when they appear due south
and at their highest - at mid-month. Transits occur an hour later on the 1st, and an hour earlier at month's end.

44

August 2015 sky & telescope
http://www.SkyandTelescope.com/almanac
Sky and Telescope - August 2015

Table of Contents for the Digital Edition of Sky and Telescope - August 2015
