Page 40 - Astronomy - October 2017 USA

PATHOF THE

PLANETS The planets in October 2017

LYN PER AND
CVn Objects visible before dawn
LMi AUR
GEM Asteroid Iris reaches
TRI
COM CNC opposition October 29
Ceres Massalia ARI
PEG
Venus passes 0.2° north LEO
BOÖ of Mars on October 5 Flora Path of the Moon
ORI TAU PSC
Path of the Sun (ecliptic)
CMi Nysa
Mars
VIR Venus SEX MON Uranus reaches its peak
Sun in mid-October
CRT HYA ERI CET
CRV CMa
LEP
SCL
PYX Asteroid Pallas reaches
ANT
opposition October 28 FOR
PUP COL CAE
VEL PHE
CEN

Moon phases Dawn Midnight

20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4
To locate the Moon in the sky, draw a line from the phase shown for the day straight up to the curved blue line.
Note: Moons vary in size due to the distance from Earth and are shown at 0h Universal Time. 31

The planets These illustrations show the size, phase, and orientation of each planet and the two brightest dwarf planets at 0h UT
for the dates in the data table at bottom. South is at the top to match the view through a telescope.
in the sky

Mercury Uranus
Mars
S
W E
Pluto
N
Saturn
Venus Ceres Jupiter Neptune
10"
Planets MERCURY VENUS MARS CERES JUPITER SATURN URANUS NEPTUNE PLUTO
Date Oct. 31 Oct. 15 Oct. 15 Oct. 15 Oct. 1 Oct. 15 Oct. 15 Oct. 15 Oct. 15
Magnitude –0.4 –3.9 1.8 8.7 –1.7 0.5 5.7 7.8 14.2
Angular size 4.9" 10.8" 3.8" 0.5" 30.9" 15.8" 3.7" 2.3" 0.1"
Illumination 93% 93% 98% 96% 100% 100% 100% 100% 100%
Distance (AU) from Earth 1.367 1.552 2.495 2.694 6.374 10.503 18.917 29.175 33.496
Distance (AU) from Sun 0.466 0.719 1.666 2.619 5.444 10.063 19.911 29.946 33.426
Right ascension (2000.0) 15h13.5m 12h04.1m 11h42.9m 8h41.0m 13h44.5m 17h29.4m 1h39.1m 22h53.6m 19h12.0m
Declination (2000.0) –19°19' 1°12' 3°07' 22°49' –9°42' –22°13' 9°39' –8°04' –21°49'

40 ASTRONOMY • OCTOBER 2017