2018 Planetary Positions
Venus shines brightly in the east before and during dawn. Look for Pollux and Castor, much fainter, to its upper left. They
form a gently curving arc with Venus that straightens out during the course of the week. The arc becomes a straight line
on the morning of the 26th. Venus is currently traveling through the sign of Cancer.
Jupiter is very low in the west-southwest during twilight. Look for fainter Spica (magnitude +1.0) 5° left or lower left of it.
Binoculars help. Jupiter is currently traveling through Libra.
Saturn glows steadily in the south-southwest at nightfall. Antares, less bright, twinkles 12° to Saturn's lower right. Saturn is currently retrograde
in expansive Sagittarius!
Uranus in Aries is in the southeastern sky in the early hours of the morning.
Distant Neptune can be found among the background stars of Pisces.
With a telescope, trying to resolve Neptune into a disk will be a troublesome task. You are going to need at least a four-inch instrument with a magnification of no less than
200-power, just to turn Neptune into a tiny blue dot of light.
Denser than the other gas giants, Neptune probably has ice and molten rock in its interior, although rotational data imply that these heavy materials are spread out rather
than concentrated in a small core. The atmosphere is swept by winds moving at up to 2,300 feet per second, the fastest found on any planet. At the equator, the winds blow
westwards (retrograde) and beyond latitude 50 degrees they become eastwards. Temperature measurements show that there are cold mid-latitude regions with a warmer equator and pole.
Neptune's thirteen known moons include Nereid, with the most eccentric orbit of any planetary satellite, seven times as distant from the planet at its farthest compared with its closest approach; and
Triton, the only large moon in the solar system with a retrograde orbit, which is an orbit in the opposite direction to that of Neptune's.
The dwarf planet Pluto lies in northern Capricorn and is highest above the southern horizon just before dawn. Search for it under a dark,
moonless sky. Pluto glows atmagnitude+14, and as a result, it is a challenge to spot. An 8-inch telescope on a perfect night brings Pluto to
the edge of visibility. For a direct view, however, you will want touse at least a 10- inch scope.
Mercury is is entering a fine morning apparition. Look for it low in the southeast in early dawn, very far lower left
of Jupiter and Mars. Don't confuse Mercury with fainter, twinklier Antares about 10° to its right or upper right.
Mars is hidden deep in the glow of sunrise. Mars is currently moving through the constellation of Scorpio.