January
January is the 1st month of the modern calendar, but it didn’t exist in the old Roman calendar. Initially, the Roman year began in the spring with March. It wasn’t until 450 BC that the winter months of January and February came into existence in their calendar. The name January comes from the name of the Roman god Janus, the god of beginnings and transitions. This made Janus ideal for the month of January. January has 31 days. On January 1st, the sun rises at 8:20 AM and sets at 5:16 PM. And on January 31st, the sun rises at 8:05 AM and sets at 5:52 PM. These times are for Boise, Idaho.
The five visible planets are located in the following constellations.
Mercury: Sagittarius and Capricornus (morning planet after midmonth)
Venus: Capricornus and Aquarius (evening planet)
Mars: Libra, Scorpius, and Ophiuchus (morning planet)
Jupiter: Sagittarius (morning planet)
Saturn: Sagittarius (evening planet until midmonth)
Mirfak
This month look for the star Mirfak, the brightest star of Perseus the Hero. Mirfak is Arabic for Elbow and astronomers have named this star Alpha Persei. Mirfak is 510 light years and 5,000 times brighter than the sun. In fact, our sun would be invisible to the unaided eye at this distance. It would require a decent amateur telescope to be able to see the sun 5,000 light years away. Mirfak shines so brightly because it is over eight times more massive than the sun. That extra mass squeezes its core harder and hotter, increasing its rate of nuclear fusion and production of starlight.
Those looking sideways at Mirfak will swear they see a haziness surrounding the star. That haze is actually a grouping of stars called the Alpha Persei Association. Associations are star clusters, but with few members. Through your binoculars, you’ll see glittering diamonds surrounding the association’s brightest member star, Mirfak.
Perseus is located in the north and pretty much overhead during January nights. If you’re lucky, you’ll discover that the second brightest star of Perseus (Algol) is dimmer than usual.
The moon reaches first quarter on the 3rd. First quarter is a perfect phase for going lunar exploring with your binoculars or small telescope. You’ll find lots of craters along the moon’s terminator, or boundary between day and night. You’ll see the mostly craters in the Southern hemisphere and more mountains in the north.
The Quadrantid meteor shower peaks on the night of the 3rd and morning of the 4th. This shower produces around 25 meteors per hour and is known to produce fireballs, or very bright meteors. The first quarter moon sets by 2:00 AM, so anytime after that should be the best time to observe this shower.
The waning gibbous moon passes between the Pleiades and Hyades star clusters on the night of the 6th. Be sure to get your binoculars out to observe these clusters. With their two-inch lens, binoculars collect about 60 times more light than your eyes. As a result, fainter stars become visible. The modest magnification provided by binoculars (around seven times) is only a small factor in making these stars more visible.
On the 7th, the moon just skirts the Hyades star cluster. This would be a good night to use your binoculars as the moon and many of the members of the Hyades are visible together. The brightest star in the Hyades is orangish Aldebaran. It’s not actually a member star since it’s only half as far away. The star represents the eye of Taurus the Bull.
After sailing through Taurus the Bull on the 6th and 7th, the moon enters the space of Gemini the Twins on the 8th. First stop is a smaller star cluster that astronomers call M-35. It’s easy to find this star cluster, just place the moon at the upper right of your binocular view. The star cluster is a smudge of light at the lower left. However, the moon is bright, so move the moon outside the field of view. Don’t expect M-35 to be as spectacular as the Pleiades.
The moon will help you identify the stars of Gemini the Twins on the 10th. On that night, the moon lies just beneath the brightest star of Gemini, Pollux. Above it is slightly fainter Castor. These stars represent the heads of the Gemini Twins. The constellation is lying on its side for now. However, as it’s setting some seven hours later, it will appear vertically in the west.
The moon is full on the 10th. If you look at it through your binoculars, you won’t detect as many craters as you would if the moon where only half full. That’s because there’s not a lot of apparent shadowing on its surface in the full phase. What you will see the best is its maria, or lunar seas. These are lava-filled impact sites created over 3.8 billion years ago when the solar system was sweeping away lingering planet-building blocks. The full moon in January is called the Wolf Moon.
Galileo turned his new telescope towards Cancer the Crab in 1609 to view a fuzzy cloud or nebula called the Praesepe. And boy was he surprised to learn that this fuzzy cloud was really some 36 tiny stars. You can see the Praesepe for yourself using binoculars and the moon will help you on the 11th. When you see it, you’ll realize why we gave it a new name, the Beehive star cluster. To see it, place the moon in the center of your binoculars and the star cluster will appear in the upper right. The star cluster is approximately the same apparent size of the moon, so you can’t overlook it. However, you will see more stars after you shift the moon outside the binocular’s field of view.
The next sign of the Zodiac after Cancer is Leo. And that’s where you’ll find the moon on the 12th. Although, you will need to stay up a little late on a Sunday night to see it. The brightest star of Leo the Lion is Regulus. The name means Little King and the star represents the heart of Leo. At a distance of 79 light years, the light you see tonight left Regulus in 1940.
The rest of Leo is stretched above and to the left of Regulus. That question mark of stars above Regulus? That represents his mane.
By the 13th, the moon crosses halfway across Leo. Regulus is to the moon’s right and the star representing the tail of Leo is on the left. Denebola and the triangle of stars it helps form represent the hindquarters of the lion.
On the morning of the 17th, the moon appears near a pearly white star named Spica. Spica is a bright star in an otherwise large and dim constellation called Virgo the Maiden. To the upper left is another bright star called Arcturus. You’ll notice a difference in color between the two stars.
The moon is at its third quarter phase on the 17th. This is another great phase to observe the moon through your binoculars. The large maria in the upper right is the Sea of Rains. The mountain range forming its southern border is called the Apennine Mountains, or Montes Apenninus. They formed 3.9 billion years ago from the impact of a planetesimal. At their highest point, the range reaches a height of 3.4 miles above its base.
Early-risers or late-sleepers, you get a chance to see a double star on the morning of the 18th. Some people with exceptionally good eyesight can separate the stars in Zubenelgenubi without optical aid. However, the rest of us mortals will need a pair of binoculars to do so. Zubenelgenubi is the star directly beneath the moon on the morning of the 18th, so you can’t confuse it for a different star.
The waning crescent moon passes close to both Mars and Antares on the morning of the 20th. Both are orangish-red in appearance. In fact, Antares is the Greek name for the Rival of Mars. However, Mars is currently located on the far side of the solar system. As a result of its small size and distance from Earth, the planet isn’t very bright. Currently Antares is significantly brighter than Mars. So make sure you don’t confuse one for the other. Mars will be fainter and closer to the moon than Antares.
One of the last times to see the moon before it approaches too close to the sun is on the morning of the 21st. If you observe it at around 6:30 AM, you have a good chance of seeing Earthshine. Your binoculars will make this observation easier by the way. Be sure to look for dark markings on the Earthshine-lit portion of the moon. Those are lunar seas or maria. The reason that you can see them is that sunlight is reflecting from Earth and illuminating the dark portion of the moon.
Mighty Jupiter becomes a morning planet this month. This is a recent event, meaning Jupiter is still very close to the sun. So it isn’t surprising that we have to wait until after 7:00 AM for Jupiter to rise. Have no fear though; Jupiter is rising earlier every day. Until then, look for the Jupiter-moon pairing in the low southeast on the 22nd. This event occurs in morning twilight, so you might want to use your binoculars. However, never use your binoculars for stargazing after the sun has risen!
The moon is new on the 24th at 2:42 PM Mountain standard time. The moon passes three degrees below the moon, so no solar eclipse this month. It will be another two days before stargazers have a chance to the see the moon again – in evening skies however.
On the 27th, the three day old moon appears in the low southwest with Venus, the Evening Star. In fact, you might notice Venus before you see the moon. The waxing crescent moon will be very thin and six degrees below Venus. This means you can see both together through your binoculars. But please wait until after the sun sets before attempting this.
References
https://en.m.wikipedia.org/wiki/January
https://www.star-facts.com/mirfak/
http://astropixels.com/ephemeris/astrocal/astrocal2020gmt.html
http://www.seasky.org/astronomy/astronomy-calendar-2020.html
https://in-the-sky.org/newscalyear.php?year=2020&maxdiff=7
https://www.messier-objects.com/tag/galileo-galilei/
https://www.timeanddate.com/astronomy/moon/full-moon-names.html
https://en.wikipedia.org/wiki/Regulus