Here is a listing of celestial events you might want to look for during these cold nights of February. All times are listed as Eastern Standard Time for the Northern Hemisphere.
Take note that we sometimes will use angular degrees to define the separation between two objects, such as (for example) the Moon and a bright planet. Keep in mind that the width of your clenched fist, held at arm’s length, measures roughly 10°.
February 1 – First Quarter Moon at 8:42 p.m. In this phase, the Moon looks like a half-Moon in the sky. One-half of the Moon is illuminated by direct sunlight while the illuminated part is increasing, on its way to becoming a full Moon.
February 5 – Look for the waxing gibbous Moon inside the large asterism known as the Winter Circle. From anywhere in the Northern Hemisphere, look for this pattern to fill up much of the eastern half of sky at nightfall. Around 9 p.m., the Winter Circle will swing to your southern sky, and then it will appear into the western sky around midnight.
February 9 – Full Moon at 2:33 a.m. In this phase, the visible Moon is fully illuminated by direct sunlight. Though the Moon is only technically in this phase for a few seconds, it is considered “full” for the entire day of the event and appears full for three days. See how this Moon got its many names in our short video, below.
February 10 – As February opens, Mercury is in the midst of one of its better evening apparitions and on this evening, it reaches greatest eastern elongation, only 18.2° from the Sun. As seen from mid-northern latitudes it then shines brightly, low in the western sky and sets more than 1½ hours after the Sun for viewers at mid-northern latitudes; look for it far to the lower right of brilliant Venus. However, over the next eight days, Mercury will rapidly fade and sink lower in the sky.
February 15 – Last Quarter Moon at 5:17 p.m. In this phase, the Moon appears as a half Moon due to the direct sunlight, the illuminated part is decreasing toward the new Moon phase.
February 18 – Occultation of Mars. A rather unusual celestial rendezvous will take place this morning, when a 24%-illuminated waning crescent Moon crosses in front of Mars, resulting in what is known as an occultation. This event will be visible over the contiguous United States and much of Canada, except northern and western sections. The midpoint of this “eclipse of Mars” will occur around 8 a.m. Eastern Time (5 a.m. Pacific Time), which means that for the eastern half of the US and Canada, it will, unfortunately, take place after sunrise, while farther west, the red planet will appear to vanish behind the Moon’s bright limb either in twilight or against a dark sky.
Mars rises around 3:40 a.m. local time and is well up in the south-southeast by dawn and crosses from the non-zodiacal constellation Ophiuchus into Sagittarius on the 11th. It remains rather inconspicuous, but its luminosity continues to increase as we gain on it in our smaller, faster orbit. The planet moves from about 16 light-minutes away in early February to within 14 light-minutes by month’s end, brightening noticeably. At its closest approach this coming October, Mars will be only 3.4 light minutes from Earth and will be dazzling; ranking as the third brightest object in the night sky after the Moon and Venus!
February 19 – Look low toward the southeast at around 5:30 a.m. local time, to see a slim (16%-illuminated) waning crescent Moon sitting about 4° to the right of Jupiter, in Sagittarius.
February 20 – For a third consecutive morning, the Moon appears in close proximity to a bright planet. This morning it is Saturn’s turn. At around 6 a.m. local time, look very low to the east-southeast horizon for the even more slender crescent moon and less than 3° to its upper left will shine Saturn. Rising at daybreak, the ringed world now begins a spectacular apparition, teaming with nearby Jupiter that will last all year.
February 23 – New Moon at 10:32 a.m. In this phase, the Moon is not illuminated by direct sunlight and is completely invisible to the naked eye.
February 26 – Mercury will be at inferior conjunction, between us and the Sun – but this time it doesn’t cross the face of the Sun (as it did back in November). Also, on this same morning, Mars passes less than 2° above Kaus Borealis, the 3rd-magnitude star marking the top of the lid of the Teapot asterism of Sagittarius.
February 27 – Although they are not particularly close to each other—separated by about half dozen degrees—Venus and a slender (16%-illuminated) crescent Moon off to its left, make for an eye-catching sight in this evening’s west-southwest sky right after sundown. Venus continues to get higher and brighter this month. The interval between sunset and Venus-set increases by about a half-hour to more than 3½ hours for viewers around 40° north latitude. And yet, the best is yet to come for Venus-watchers at mid-northern latitudes. If we check Venus’s location in the sky nightly, at the same stage of twilight, the planet will seem to be making a slow-motion vault during the next three months—the highest, in fact, of its 8-year cycle. The peak of the vault is reached in late March, after which the planet passes quite close to the Pleiades in early April and becomes its very brightest in early May.
February 29 – Today is leap day, an artifact that dates back to 46 BC when Julius Caesar took the advice of an Alexandrian astronomer. That astronomer, Sosigenes, knew from Egyptian experience that the solar year was about 365.25 days in length. So to account for that residual quarter of a day, an extra day—leap day—was added to the calendar every four years.
By Farmers’ Almanac Astronomer Joe Rao. This calendar is adapted from “Skylog,” a regular feature appearing in Natural History magazine written by Mr. Rao since 1995.