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As the New Year opens, we find the evening sky completely devoid of any bright planets. All of the action takes place well after the witching hour of midnight, but there is a lot to be seen early in the month for those who set their alarm clocks and rise before the sun. Jupiter and Mars come up over the east-southeast horizon by 3 a.m. and are near to each other for the first half of the month; interacting closely with each other with a tight conjunction on the morning of the 7th. We must wait until after the break of dawn to catch Saturn, very low near the east-southeast horizon during the second week of January, but it too will have a companion: Mercury; interesting how the speedy messenger of the gods will have a meeting with the slow-moving god of time on the morning of the 13th.

The only planet completely out of the loop is the one that usually dominates all the others: Venus. But she is in the midst of making a slow transition from the morning to the evening sky and will not return for viewing until next month. 

In our schedule, remember that when measuring the angular separation between two celestial objects, your clenched fist held at arm's length measures roughly 10-degrees. Here, we present a schedule below which provides some of the best planet viewing times as well directing you as to where to look to see them.

On Monday, January 1, Mercury will reach its greatest angle west of the sun, when it will be visible low in the eastern sky for about an hour before sunrise. In a telescope the planet will exhibit a waxing gibbous phase. With Mercury well above a shallow morning ecliptic (green line), this apparition is a good one for northern hemisphere observers, but a poor one for observers in the southern hemisphere.
On Monday, January 1, Mercury will reach its greatest angle west of the sun, when it will be visible low in the eastern sky for about an hour before sunrise. In a telescope the planet will exhibit a waxing gibbous phase. With Mercury well above a shallow morning ecliptic (green line), this apparition is a good one for northern hemisphere observers, but a poor one for observers in the southern hemisphere.
Credit: SkySafari App

Mercury – Mercury stands at greatest elongation (23-degrees west of the sun) on New Year's Day. During the first week of the New Year, as seen from mid-northern latitudes, this speedy zero magnitude planet rises in the southeast before morning twilight begins. This favorable circumstance will not recur until December 2018. Mercury can be easily followed with the naked eye until about the 15th (passing a dimmer Saturn along the way on the 13th) and then as it sinks back into the increasingly bright twilight glow, you can then track it with binoculars for perhaps another week.

Venus is hidden from view until well after solar conjunction on January 9. The best opportunities to see Venus during January are in the last few evenings of the month, when it will start to emerge from the twilight in the west-southwestern evening sky.
Venus is hidden from view until well after solar conjunction on January 9. The best opportunities to see Venus during January are in the last few evenings of the month, when it will start to emerge from the twilight in the west-southwestern evening sky.
Credit: SkySafari App

Venus – remains hidden in the Sun's glare all month, reaching superior conjunction (passing behind the sun) on Jan. 9th. It will reappear very low in the sunset in February.

Sunrise seen over Earth.
Sunrise seen over Earth.
Credit: NASA

Earth – will be closest to the sun for the year at 1:00 a.m. EST; a distance of 91,401,983 miles. We are 3.3 percent closer to the sun than we will be when the Earth is at aphelion next July 6th.

In January, look for Mars and Jupiter in the predawn sky.
In January, look for Mars and Jupiter in the predawn sky.
Credit: SkySafari App

Mars – now appears respectively bright at magnitude +1.4. By the end of the month it brightens to +1.2, because the Earth edges 25,563,000 miles closer to it during January. Through a small telescope, the red planet is still a tiny featureless blob; you would need a 14-inch telescope magnifying at 360-power to make Mars appear as large as the full moon does to the unaided eye. Check out the southeast sky at around 5:30 a.m. on the 7th, for Mars passing only 0.2-degrees south of Jupiter, and then on the 11th for a view of an isosceles triangle formed by the waning crescent moon, brilliant Jupiter (magnitude -1.9) and orange-yellow Mars. 

Bright Jupiter continues to climb the eastern pre-dawn sky during January, slowly moving eastward through central Libra. On Saturday, January 6, Mars will pass very close to Jupiter. On both Saturday and Sunday morning, observers in the Americas will see the two planets separated by about 0.33 degrees (less than a full moon's diameter). A few mornings later on Thursday, January 11, the waning crescent moon will join Jupiter and Mars. All three objects will fit within the field of view of binoculars. Galilean moon shadow transits occur frequently during January, including several double shadow events.
Bright Jupiter continues to climb the eastern pre-dawn sky during January, slowly moving eastward through central Libra. On Saturday, January 6, Mars will pass very close to Jupiter. On both Saturday and Sunday morning, observers in the Americas will see the two planets separated by about 0.33 degrees (less than a full moon's diameter). A few mornings later on Thursday, January 11, the waning crescent moon will join Jupiter and Mars. All three objects will fit within the field of view of binoculars. Galilean moon shadow transits occur frequently during January, including several double shadow events.
Credit: SkySafari App

Jupiter – spends the first half of January in the company of Mars. On the morning of the 7th it engages with Mars in what the Observer's Handbook of the Royal Astronomical of Canada describes as a "splendid dawn conjunction." The best time this month to observe Jupiter with a telescope is in morning twilight when the atmospheric seeing is often excellent, but even then it is not very high in the southeast for observers at mid-northern latitudes.

Low in the southeastern pre-dawn sky of Monday, January 15, the old moon's very thin crescent can be glimpsed sitting three degrees to the left of Mercury. Meanwhile, Saturn will be positioned three degrees to the upper right of Mercury. All three objects will fit into the field of view of binoculars (red circle).
Low in the southeastern pre-dawn sky of Monday, January 15, the old moon's very thin crescent can be glimpsed sitting three degrees to the left of Mercury. Meanwhile, Saturn will be positioned three degrees to the upper right of Mercury. All three objects will fit into the field of view of binoculars (red circle).
Credit: SkySafari App

Saturn – begins its 2018 apparition about 10 days or so into the New Year. Using binoculars during the second week of January, see how soon you can spot Saturn to the lower left of Mercury at the southeast horizon about an hour before sunrise. On the morning of the 13th it is 0.7-degrees to the upper left of Mercury, but appears only half as bright. The very next morning, about an hour before sunrise, look for a very narrow crescent moon (6 percent illuminated) low in the southeast sky and about 6 to 8-degrees to its lower left will be Saturn and Mercury.

Joe Rao serves as an instructor and guest lecturer at New York's Hayden Planetarium. He writes about astronomy for Natural History magazine, the Farmer's Almanac and other publications, and he is also an on-camera meteorologist for Verizon Fios1 News, based in Rye Brook, NY