Celestial Treasure Hunt, Follow the Path of the Sun
by Rod Kennedy
The path the sun appears to take through the sky is known as the ecliptic. This path is an imaginary line that shows the orbit of the Earth around the sun. During the day, the Sun marks the ecliptic and the stars are hidden. At night the planets and the moon show us the line of the ecliptic, and this gives us a “road” to finding more interesting celestial objects.
April begins with two bright planets visible in the western sky just after sunset. The lowest is the planet Jupiter. This is the last chance to see Jupiter because Earth’s orbit is slowly moving it toward the glare of the setting Sun. After the end of April, Jupiter will not be visible until next fall. Higher in the sky is Venus, which is the brighter of the two planets. For the first few days of April, Venus will be within two degrees of the Pleiades. Through binoculars or a small telescope this should be an amazing sight. The moon will also get into the act; passing Jupiter on April 22, the Pleiades on the 23 and Venus on the 24.
Looking high in the Southeast we find the planet Mars. Mars will appear as a distinct red-orange light slightly to the east of the star Regulus in Leo the Lion. Mars recently entered “summer” which will allow telescope users on Earth to clearly see the ice cap at Mars’s north pole. The waxing gibbous moon will pass less than ten degrees below Mars on the night of April 3rd.
Looking east after 9:00 PM we find the golden planet Saturn. Saturn will be to the north of the bright blue star Spica in Virgo the Maiden. While it is tempting to point a telescope at Saturn when if first appears, it is better to wait until well after midnight when Saturn is higher in the southern sky. The full moon will pass to the South of Saturn on the night of April 6.
The moon is also a guide to other celestial treasures. On the night of April 25, the waxing crescent moon will be almost half way between the Crab Nebula (M1) in Taurus the Bull and M35 in Gemini the Twins. The Crab Nebula is a super nova remnant, the remains of a star that blew itself up and was visible in the year 1054. M35 is an open star cluster containing several hundred stars. This cluster is a stunning 2,800 light years away. On April 28 the first quarter moon will be just south of the Beehive cluster (M44) in Cancer the Crab. Because the stars of Cancer are extremely faint, the moon will have to serve as a guide for finding this beautiful star cluster. The Beehive will be about six degrees above the moon. Binoculars or a small telescope will be needed to find it, but the search will be worth it. Looking about the same distance to the East (left) of the moon is the King Cobra cluster (M67). This cluster does indeed resemble a cobra with its hood open.
The Sun, Moon and planets move through the constellations at their stately pace year after year, generation after generation. The orbits of the objects in our solar system gave importance to the constellations that were along that line. Like landmarks pointing to a favorite camping spot or fishing hole, the ecliptic serves as a kind of roadmap to finding some unique celestial treasures.