For most of the world, no full moon will occur in February, because January got two. But this month, you may be able to witness a partial solar eclipse — that is, if you can make it to southern South America or Antarctica.
For skywatchers in many parts of the world, January featured a full moon on Jan. 1 and Jan. 31. There were some exceptions, though. For example, in Sydney, the moon reached its peak fullness on the morning of Feb. 1 local time, rather than on Jan. 31. In North America, the next full moon will take place on March 1.
Because full moons fall just outside the beginning and end of February, the new moon occurs toward the middle of the month. During this lunar phase, the moon's surface is completely in shadow, rendering it more or less invisible in the night sky. The moon reaches peak newness in New York at 4:05 p.m. EST on Feb. 15, which is when the partial solar eclipse happens. (See below for more details.) Nebulous sky objects such as the Orion Nebula and the Milky Way will be easier to see with no moonlight to overwhelm them. The following times are for New York City, according to timeanddate.com. [Full Moon Names 2018: From Wolf Moons to Cold Moons]
In February, winter constellations will still be high and easily visible in mid-northern latitudes. For example, at about 6 p.m. on Feb. 1 for people in the Eastern Time Zone, the constellation Orion, the hunter, is well up in the eastern sky. Canis Major, the Big Dog, is close by, almost entirely risen, and from a dark-sky site, observers can trace the constellation Eridanus, the river, from Orion's feet. From the middle star of Orion's Belt, called Alnilam (Epsilon Orionis), you can trace the "sword" of Orion, a line of fainter stars that clusters around the Orion Nebula. Above Orion (in the northern latitudes; Southern Hemisphere observers will see Orion upside down), Taurus is visible, and west of the bull is Gemini. By about 10 p.m., the constellation Leo will be high enough to be recognized, and Virgo will emerge completely above the horizon about an hour after that.
Night owls can see the first summer stars appear, as Vega and Deneb — two corners of the Summer Triangle — appear at about 2:30 a.m. on Feb. 1, and by the end of the month, they will be rising closer to midnight.
On Feb. 1, Venus will be visible as an evening "star," though it will be less than 5 degrees above the horizon at sunset (which happens at 5:13 p.m. for viewers in New York City), and the planet itself will set at 5:33 p.m. As the month progresses, the planet will spend a bit more time in the sky and will be easier to see after sunset. By Feb. 15, it will set at 6:08 p.m., while sunset occurs at 5:30 p.m. By month's end, Venus will set at 6:40 p.m., nearly an hour after the sun sets, at 5:46 p.m.
On Feb. 1, the moon will rise at 6:47 p.m. in New York and will be just past full, a waning gibbous. Naked-eye planets other than Venus won't be up until much later; Jupiterdoesn't get above the horizon until about 1:30 a.m., while Mars follows about an hour later. Saturn doesn't rise until 4:50 a.m. on Feb. 2. Seeing the naked-eye outer planets will be easier as the month progresses; by Feb. 15, Jupiter rises at 12:38 a.m., while Mars rises at 2:17 a.m.; Saturn will follow at 4:04 a.m. By month's end, Jupiter will rise before midnight in the constellation Libra, Mars will rise at 2:03 a.m. in Ophiuchus and Saturn is up by 12:30 a.m. in Sagittarius.
Meanwhile, Mercury will be a morning "star," rising at 6:45 a.m., with the sun following only 15 minutes later. This makes Mercury tough to spot because by the time the planet rises, the sky will already be getting a bit light. Mercury will get only 2.6 degrees above the horizon at sunrise on Feb. 1, so seeing it will require an absolutely flat horizon and a lot of luck. By Feb. 15, it will be too close to the sun to see. Mercury will emerge as an evening "star" a few days later, and by Feb. 28, it will be a full 5 degrees above the horizon at about 6 p.m.; the sun sets about 15 minutes before that.
Speaking of summer "stars," Mars will start the month in Scorpius, a constellation that, in northern latitudes, tends to reach its highest points in the sky during the warmer months. According to Greek legend (per Hesiod), this was the scorpion that killed Orion. Orion, a great hunter, had threatened to kill every beast on Earth; the goddess of the hunt, Artemis, and the goddess of the Earth, Gaea, were so upset that Gaea sent the scorpion to kill Orion. Zeus, the king of the gods, felt Orion should be honored as a hunter, though, so he placed both Orion and Scorpio in the sky — but on opposite sides, so one sets just as the other rises.
A partial solar eclipse
A solar eclipse occurs when the moon passes between Earth and the sun, briefly blocking out the star's disk. A total solar eclipse occurs when the moon completely covers the solar disk; a partial eclipse (which is far more common) occurs when only part of the solar disk is blocked. NEVER look directly at the sun or the partially eclipsed sun without eye protection. You can also observe the eclipse using a pinhole projector.
The partial solar eclipse of February 2018 will be magnitude 0.599, meaning that the moon’s face will reach across that fraction of the sun’s diameter. (Note this is not the same as the percentage of the sun that will be covered.) Unfortunately for most people, the point of greatest eclipse — where the largest percentage of the sun's face will appear to be covered — will be on the coast of Antarctica, east of the Antarctic Peninsula. The central path of the eclipse will run from a point a few miles east of Asunción, Paraguay, southeast through Argentina and Uruguay and out into the South Atlantic before hitting the Antarctic coast and passing through the frozen continent until it reaches the Indian Ocean south of Tasmania, where it ends.
Viewers in the southern part of South America will see a partial eclipse — one that covers less of the sun than at the point of greatest eclipse in Antarctica. Viewers in Montevideo, Uruguay, for example, will see an eclipse of magnitude 0.181, for a maximum of 8.8 percent of the sun's face covered, and in Buenos Aires, Argentina, it will be magnitude 0.165, or about 7.7 percent coverage. The inhabited area with the best view of the eclipse will be Stanley, Falkland Islands, where a magnitude-0.398 eclipse will occur, meaning 28 percent of the sun will be obscured by the moon.
In Montevideo, the eclipse will start at 6:34 p.m. local time, and maximum eclipse for that location will happen at 7:11 p.m.; the eclipse will end at 7:35 p.m. As the eclipse ends, the sun will be setting; sunset in Montevideo on Feb. 15 will be at 7:38 p.m. local time. Times in Buenos Aires will be similar. The moon's shadow will touch the sun at 6:36 p.m., and maximum eclipse will be at 7:12 p.m.; the eclipse will end at 7:44 p.m., and sunset will happen only 2 minutes later.
For the Falkland Islands location, the eclipse will start at 4:46 p.m. and will reach maximum at 5:42 p.m. It ends at 6:34 p.m. (Sunset isn't until 8:16 p.m. local time.) All eclipse times are compiled by eclipsewise.com, where you can see other cities in South America as well.