Skywatch Line for Friday, January 2, through Sunday, January 4, written by Sam Salem

This is Dudley Observatory’s Skywatch Line for Friday, January 2, through Sunday, January 4, written by Sam Salem.

On Friday, Sun rises at 7:26am and sets at 4:33pm; Moon sets at 7:02am and rises at 3:29pm.

Full Moon occurs at 5:03am, Saturday morning. The January full Moon is the Wolf Moon and it’s a supermoon. It will glow near bright Jupiter and the twin stars of Gemini, Castor and Pollux. Jupiter sits 4° degrees south of the Moon.

The Earth’s closest point to the Sun, perihelion, occurs on Saturday. In early January, the Earth is about 3% closer to the Sun, roughly 1.5 million miles than during Earth’s farthest point, aphelion, in early July.

The predicted peak for the Quadrantid meteor shower occurs on Sunday. However, the light of the bright waning gibbous Moon will interfere with all but the brightest Quadrantids. Moreover, the shower’s predicted peak almost exactly a half day out of sync with the best meteor-watching hours for North America. Luckily, the Quadrantids often produce bright meteors known as fireballs.

Asteroid 40 Harmonia reaches opposition at 10am on Friday. Try to catch the 9th-magnitude main-belt Asteroid in binoculars or a telescope on Friday evening in Gemini, where it lies just under 2.5° southeast of 3rd-magnitude Mebsuta (Epsilon [ε] Geminorum) and above Jupiter as the constellation rises in the evening sky. The bright, nearly Full Moon sits nearby in the constellation Taurus, which may hinder the view. However, Harmonia will remain in roughly the same part of the sky for a while, moving slowly against the background stars. You can come back and search for it again after the Moon has begun to wane and rises later in the evening.

A main-belt asteroid is a rocky body orbiting the Sun in the vast region between Mars and Jupiter. The belt is the remnants from the Solar System’s formation that never became planets, with millions existing, though sparsely spread. These main-belt objects are classified by composition (C-type, S-type, M-type) and clustered into families, notably featuring the dwarf planet Ceres.

Jupiter, magnitude –2.6 in eastern Gemini, is nearing its January 10th opposition. It rises in the east-northeast in twilight dominating the eastern sky as the evening proceeds, then the high southeast. Jupiter is highest in the south by midnight.

On Friday, Jupiter’s Great Red Spot should cross Jupiter’s central meridian, the line down its middle from pole to pole, around 8:39pm. The spot is closer to Jupiter’s central meridian than to the limb for 50 minutes before and after its transit times.

On Sunday, Jupiter’s Great Red Spot should cross the Jupiter’s central meridian around 10:16pm.

Saturn, magnitude +1.1 at the Aquarius-Pisces border, is the brightest object high in the south-southwest at nightfall, lower left of the Great Square of Pegasus. It gets lower in

the southwest through the evening and sets around 11pm. Below Saturn, by almost three fists at arm’s length, you’ll find Fomalhaut, similar to Saturn in brightness.

Friday marks the sixty seventh anniversary of launching the first spacecraft to reach the vicinity of the Moon and enter heliocentric orbit. Launched by the Soviet Union, Luna 1, was the first craft to leave Earth’s gravity in 1959, achieving Earth escape velocity and becoming the first human-made object to orbit the Sun, between Earth and Mars.