On Jan. 2, Earth is closest to sun in 2021 at a distance of 91.5 million miles.
The reason for the seasons is the tilt of the Earth’s axis as we orbit the sun. In early winter, the Earth’s northern axis is tipped away from the sun, causing a low sky path of the sun and shorter daylight hours.
In early summer, the Earth’s northern axis is tipped towards the sun, causing a high sky path for the sun and longer daylight hours. We have the latest sunrises for Standard Time at 7:35 a.m. from Jan. 1 to 10.
At the start of January, dawn begins at 6:30 a.m., sunrise is 7:35 a.m., midday is 12:18 p.m., sunset is 5:02 p.m., dusk ends at 6:05, giving us 9 hours and 27 minutes of sunlight that day.
The sun shines in front of Sagittarius till Jan. 18, then moves into Capricornus.
The moon was full in late December, so early January will have the moon moving into the morning sky. On Jan. 13, the moon disappears in the eastern dawn; mid-January has the moon as a crescent in the western dusk.
On Jan. 20, the evening moon will appear half full with the planet Mars close by. This is the best time to view the moon’s craters with a telescope; for along the left side of the moon, the sun there is rising, lighting up the raised rims of the craters.
The moon is full on Jan. 28, appearing in the star group Cancer.
The 2 brightest planets, Venus and Jupiter are close to the horizon in early January, Venus in the eastern dawn and Jupiter in the southwestern dusk. The Earth’s motion about the sun during January will close these planets from view by the end of the month.
Jupiter will next be seen in March in the eastern dawn while Venus won’t be seen in the western dusk till late spring.
January evenings will have the majestic star group Orion with his 3-star belt in the southeastern sky. Orion’s belt points up and right to Aldebaran, the eye star of Taurus. Late on January evenings, the belt points down and left to Sirius, the night’s brightest star.
Nearly overhead is the bright golden star Capella. Low in the northwestern dusk is Vega, a white-blue star; Vega will been in view in the evening sky till May and will soon be lost in the sun’s glare.
As January ends, sunrise is at 7:23 a.m., sunset is 5:34 p.m. with 10 hours and 10 minutes of sunlight.
To get an email copy of 2021 Night Sky Highlights (2 pages), request it from firstname.lastname@example.org.
An easy-to-use current monthly sky chart is available from Telescopes.com; you can print it out in black/white.