Skylights: February 2025

Sun

The Sun is now climbing out of its most southerly position in the sky, resulting in earlier sunrises, later sunsets, and longer hours of daylight. The first sunset in the 5:00pm hour is on the 1st.

Midway through the month, February 14 also marks the halfway point in the Sun’s northward progression towards equinox, declination -12° 43’ 09”.

After traveling through Capricornus for the past 27.5 days, the Sun crosses into Aquarius on the 16th.

Finally, the first day of the year with at least eleven hours of daylight (the interval between sunrise and sunset) occurs on the 24th.

Moon

On the 1st, the 15.1% illuminated crescent Moon is located between Venus (2.1° to the northwest) and Neptune (0.8° to the south-southeast), while the two planets are just 3.3° apart from each other.

The Moon is at first quarter phase at 3:02am on the 5th, in Aries. Later in the evening of the 5th, it is 4.8° north-northeast of Uranus. A few hours later, the Moon occults the Pleiades, but it occurs after moonset in the eastern US. Look for the 60% illuminated gibbous within just 0.5° west of the cluster just before moonset, which occurs at 2:00am on the 6th.

Later on the 6th, The Moon passes Jupiter, 4.9° to its north. On the 7th, it is just 0.8° east-southeast of Elnath (beta Tauri). As this occurs during evening twilight, it presents a good opportunity to test your ability to detect bright stars during non-dark hours. The gibbous Moon will be clearly visible high in the eastern sky before sunset. Aim your telescope at it, and start looking for the magnitude 1.7 star.

There is no occultation of Mars in store for us this month, but the Moon does appear just 2.2° east of the Red Planet on the 9th. A few hours later, just past midnight on the 10th, it is 2.1° south of Pollux, in Gemini.

Early on the 11th, the nearly full Moon is 1.8° northeast of the open star cluster M44, the Beehive, in Cancer. Due to the brightness of the Moon, this pairing will look best with a telescope capable of providing a low magnification, and wide field of view.

For moonrise observers and photographers, the best opportunity occurs on the evening before full Moon, the 11th, when it rises at 4:18pm, 55 minutes before sunset.

The Moon is full at 8:53am on the 12th, in Leo. This is the annual Snow Moon, and since it is below the horizon at the moment it turns full, the best time to observe it is right at sunrise on the 12th. The Moon sets at 7:01am. The following evening, the Moon rises 1.5° northeast of Regulus.

At midnight on the 19th, the waning gibbous Moon is 4.4° south-southwest of the wide double star Zubenelgenubi (alpha Librae). This pairing should present a great view with binoculars. 

The Moon is last quarter at 12:32pm on the 20th, in Scorpius. At moonrise on the 21st, it passes just 0.8° south-southeast of Antares, the brightest star in that constellation. 

The Moon is new at 7:45pm on the 27, beginning Lunation 1263.

An opportunity to observe a very young crescent (22 hours) Moon occurs after sunset on the 28th. The Moon will be just 1.0% illuminated, and 1.6° north-northwest (around the 1 o’clock position) of Saturn.

Mercury

Mercury is at superior conjunction on the 9th, and will not be visible during the first half of the month. By the third week of February, it will be visible in the evening sky after sunset, and over the next several weeks it will undergo its best evening appearance of the year. From the 24th through March 17, the innermost planet sets over an hour after sunset. Also on the 24th, get one last look at Saturn as it appears just 1.6° south, southeast of Mercury.

On the 28th, the 1.1% illuminated, 1.2-day old crescent Moon is 3.4° below (southwest of) Mercury.

Venus

While Venus reached its greatest apparent elongation from the Sun in early January, its latest set time occurs at 8:53pm on February 4th, almost four hours past sunset.

Venus spends the month within Pisces, and is exhibiting its crescent phase, which gets thinner each evening, and the planet’s apparent diameter increases, as it continues moving closer to Earth.

Venus in the evening sky is often susceptible to atmospheric turbulence due to temperature changes after sunset and the planet usually being low over the horizon, with a lot of airmass for its light to pass through. This usually causes prismatic effects when the bright planet is close to the horizon, say, within 5° elevation. This apparition of Venus, however, has the planet on a steep angle off the horizon near maximum elongation, so the planet is much higher in the sky and away from most of the turbulent air. As such, you can easily track its changing phases through a small telescope. However, you may find it helpful to reduce its brightness with a filter, such as a deep red or neutral density (Moon) filter.

Venus shines at its brightest, magnitude -4.9, on the 19th. Through a telescope, the planet’s disk appears larger than that of Jupiter, and shows an obvious crescent phase.

On the 27th, Venus is stationary, and begins moving westward toward the increasingly later-setting Sun. Still shining at a brilliant magnitude -4.8, it sets three hours after the Sun. By the end of the month, Its enormous 49 arcsecond disk will appear larger than any other planet ever appears. Even a small telescope will reveal its diminishing crescent, now at just 15%.

Mars

Mars is visible all night, shining brightly in Gemini. On the 9th, the waxing gibbous Moon is 2.2° east of Mars.

Mars forms an isosceles triangle with the constellation’s twin stars Castor and Pollux from around the 17th through the end of the month. The Red Planet reaches the end of its retrograde loop on the 24th, and moves eastward thereafter.

You’ll also notice that Mars isn’t quite as bright as it was a few weeks ago, although it is still brighter than all of the stars in the winter sky except Sirius. Although Earth is receding from Mars, its 12 arcsecond globe will still reveal features in a telescope during nights of steady seeing.

Jupiter

Jupiter is in Taurus, high in the south after sunset. It reaches its stationary point on the 11th, after which it resumes its prograde (eastward) motion. Note how it is almost directly north of Aldebaran, and over the coming weeks, as it moves eastward within Taurus, and the star patterns move westward with the progressing season, Jupiter will retain its relative position almost directly above Aldebaran as it slowly gains apparent distance from the star.

The pairing of the giant planet with the eye of Taurus closely mirrors the Gemini twins on the opposite side of the Winter Hexagon asterism, with similar separation and orientation. It crosses the line connecting Aldebaran and Capella on the 27th.

Jupiter’s Moons

On the evening of the 2nd, beginning with Io’s reappearance from eclipse at 7:20pm, all four Galilean moons are arranged in order of their orbital distance, extending to the east of Jupiter.

On the 7th, a peculiar double pairing, best observed around 10:30pm, has Europa and Io in a close pair to the west of Jupiter, with Ganymede and Callisto in a parallel, wider, and more distant pairing on the east side.

Just after dusk on the 9th, Jupiter appears to have only two moons, Callisto to the east and Ganymede to the west. Europa emerges from eclipse at 6:34pm, followed by Io at 9:15pm.

Another orbital distance arrangement occurs, this time to the west of the planet, early on the 12th. Io swaps places with Europa at 7:20pm.

Ganymede goes through eclipse from 7:18pm to 9:52pm on the 14th.

On the 16th, Jupiter again appears to have just its two outer moons after Io goes into occultation at 7:20pm. Callisto sails over Jupiter’s north polar cap, is closest to the planet at 9:00pm, and solitary Ganymede is visible to the east of the planet. A few minutes later, beginning at 9:12pm, Europa emerges from eclipse, followed by Io at 11:09pm.

An eclipse of Ganymede occurs from 11:09pm on the 21st until after the planet sets at 1:44pm.

On the 23rd, Jupiter shows only its two outermost moons after Europa (6:23pm) and Io (9:33pm) are occulted by the planet, but only after Europa briefly reappears from occultation and immediately goes into eclipse at 9:07pm and 9:13pm, respectively. The four moons are once again visible at 1:08am.

The four Galilean moons appear close to Jupiter on the 23rd, in order of Io, Callisto, Ganymede, and Europa on its east side. Io moves across Jupiter while the other three move in closer later in the night.

Another close arrangement of the moons, this time with Europa, Callisto, and Ganymede to the west, is visible after dusk on the 25th. Io reemerges at 7:34pm. 

The moons form two parallel pairs at 12:30am on the 27th, with Europa and Io making the inner pair, and Ganymede and Callisto making up the outer pair.

Saturn

The optimal time for observing Saturn has now passed, but as we get closer to crossing its equatorial plane late next month, it’s worth trying to get a few last looks.

Saturn is still located in Aquarius, appearing almost directly below brilliant Venus throughout the month, its apparent distance expanding from 11.5° on the 1st to 19° at mid-month. This places it rather low over the southwestern horizon, and you’ll have to begin viewing during twilight.

While Saturn season is just about over, it’s worth watching as long as possible this year as we’re approaching ring plane crossing on March 23. You can still spot Saturn low in the west-southwestern sky after sunset, and on the 24th, Mercury, shining twice as brightly as Saturn, lies just 1.6° to the northwest of Saturn on the 24th, presenting a nice pairing for binoculars or a wide-field telescope. The ring plane angle is now just 2.3°.

Mercury can be found 1.7° north of Saturn on the 25th, and the 1.0% illuminated crescent Moon is 1.6° north-northwest of the ringed planet on the 28th.

Uranus

Uranus is high in the south in the early evening hours, near the border of Aries and Taurus. It is located 2.9° east-southeast of magnitude 4.4 Botein (delta Arietis). It sets before 2:00am in early February.

Uranus is easy to locate about 8° southwest of the Pleiades cluster. At magnitude 5.7, it can be seen with binoculars 3° east-southeast of magnitude 4.4 Botein (delta Arietis). The waxing gibbous Moon is 4.8° north-northeast of Uranus on the 5th.

Uranus is at quadrature, 90° east of the Sun, on the 11th. It sets at 12:50am.

The seventh planet reaches its stationary point on the 30th, and then resumes its prograde (eastward) motion.

Uranus sets just after midnight at the end of the month.

Neptune

Neptune is low in the southwestern sky after sunset. It shines at magnitude 7.8 in Pisces, about 10° east-northeast of Saturn, and 4.8° southeast of lambda Piscium. You can also use Venus as a guide early in the month, as the brilliant planet will be just 4.5° north of it on the 4th. The distant planet sets at 8:30pm.

As the month progresses, Neptune is getting low in the west after sunset, and as a result is becoming more challenging to observe. At the end of the month, Neptune sets before the end of astronomical twilight.

Minor Planets

Ceres is at conjunction on the 14th, and is not visible this month. Likewise, Pluto, which was at conjunction on January 21st, will not be visible until May.

4 Vesta is in the morning sky, slowly brightening from magnitude 7.5 to 7.0. It passes 1.5° south of mu Virginis on the 2nd, and crosses into Libra on the 6th.

On the 19th and 20th, it lies within 0.2° south of the 11th magnitude elliptical galaxy NGC 5812, 1° north of delta Librae.

2 Pallas is once again visible in our morning sky. It is traveling eastward through Aquila, and on the 23rd and 24th, the magnitude 10.5 asteroid will be just 0.9° south of Alshain (beta Aquilae), the magnitude 3.7 star that lies just to the south of Altair.

Stars

February’s evening skies present us with the full breadth of the winter constellations, ready for viewing just after dark. The Winter Hexagon, marking the brightest stars of Auriga, Gemini, Taurus, Orion, Canis Major and Canis Minor, is high in the sky throughout the month. Not to be overlooked, despite their lack of brighter stars, the constellations of Monoceros, Puppis, and Lepus are all well-placed for exploration, and given their proximity to the Milky Way, there are numerous deep-sky treasures awaiting your gaze.

If you’d like to try a relatively easy observing challenge, try for the globular cluster Caldwell 73 (NGC 1851), in the little-known (to us northern hemisphere observers) constellation Columba, the Dove. The cluster’s southerly declination of -40° brings it to an elevation no higher than 8° in our sky, but it is slightly larger, brighter, and has a more concentrated core than the more familiar Messier 79, located 15° to its north, making it accessible to small telescopes and even binoculars under a moderately dark sky.

To the northeast, Ursa Major is assuming its winter “nose-up” position, with the prominent Big Dipper asterism pouring its contents back over its handle.

In the east, early spring’s constellations Hydra and Leo are beginning to appear. A few hours into darkness, Arcturus, in Bootes, followed by Corona Borealis enter the sky. As we’re still waiting for the expected one-in-eighty-years outburst of T Coronae Borealis, the “Blaze Star,” keep watching this part of the sky.

Have you noticed a relatively bright star hanging low in the northwest after evening twilight? This is Deneb, in Cygnus, the last remaining hold out from last season’s appearance of the Summer Triangle. This is the time of year to see how long you can continue to observe Deneb, and also to note how far into the north it gets before setting. It is so far north, in fact, that when it does set, it is out of view for just under three hours before rising again in the north-northeast. With the reappearance of some of the summer stars, we’re reminded that the warmer nights, and the sounds of nocturnal life, are just a few weeks away.