Skywatcher's Guide: February and March 2023

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Stars and Constellations

In February, the center of the Milky Way is well below the horizon, but there is still a good portion of our galaxy we can see streaking high across the sky. The fall sky is still prominent in the west.  The "W" of Cassiopeia is high in the northwest. In the absence of the Big Dipper (part of our spring sky) Cassiopeia can be used to locate the north star: The top (open side) of the "W" faces to the north, so in that direction look for a star about the same brightness as the main stars in Casssiopeia, and that will most likely be Polaris.  The Big Dipper is beginning to come up again, but it is likely to be hidden behind trees and mountains along the horizon.  Next, the Great Square of Pegasus is getting low in the west.  Andromeda is just above that, with Perseus even higher, nearly in the middle of the sky.  Finally, the winter sky is now getting very high in the east.  Taurus the bull with the bright star Aldebaran is very high (near Perseus) along with the Pleiades (aka the seven sisters or Subaru) star cluster.  Auriga the charioteer with the bright star Capella is very high as well, slightly more to the northeast.  Gemini the twins is just below that in the east, and Canis Minor (the little dog) with the bright star Procyon is just below.  Orion the hunter is up in the southeast, with his easily recognizable belt, and Canis Major (the big dog) is just below.

In March, the winter portion of the Milky Way continues to streak across the sky.  The fall constellations are now getting low in the west, with Pegasus now partly below the horizon.  The winter constellations are now in the middle of the sky, and some of the spring constellations are beginning to come up.  Leo the lion is just above the horizon in the east, and the Big Dipper (Ursa Major) is now up in the northeast.

Interesting Stars Visible in February and March

Name / Designation Apparent Magnitude
(lower = brighter)
Distance
(light-years)
Notes
Sirius -1.44 8.6  
Arcturus -0.05 36.7  
Capella 0.08 42  
Rigel 0.18 770  
Procyon 0.4 11  
Betelgeuse 0.45 427  
Aldeberan 0.87 65  
Spica 0.98 262  
Pollux 1.16 38  
Markab 1.25 140  
Regulus 1.36 77 means "Little King"
Castor 1.58 52  
Polaris 1.97 431  
Alpheratz or Sirrah 2.07 97  
Mirach 2.07 199  
Algol 2.09 93 variable star
Denebola 2.14 36.2  
Almak 2.1 / 5.0 & 6.3 355  triple star system w/ 64 yr orbit
Eta Cassiopeiae 3.5 / 7.4 19 480 yr orbit

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Solar System

Mercury will be visible in the morning sky before sunrise in February but will be passing behind the Sun in mid-March.

Venus is now visible in the west after sunset and will get higher each evening.

Mars is high in the sky after sunset in February but slowly moves towards the western horizon as we get into March.

Jupiter can still be spotted after sunset until mid-March but will be lost in the Sun's glare later in the month.

Saturn is passing behind the Sun in February but will emerge in the morning sky in late March.

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Jupiter Great Red Spot Transits in February and March (during observatory hours)

Note: The GRS is visible on the disk of Jupiter for 50 minutes before and after meridian transit time.

DATE MERIDIAN TRANSIT TIME
03/03/23 07:01 PM

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Calendar of Night Sky Events

Date Event
02/05/23 Full Moon.
02/13/23 Last Quarter Moon.
02/16/23 Appulse of Venus and Neptune. — Separated by 0.6°.
02/16/23 Saturn at conjunction. — Passing behind the Sun.
02/20/23 New Moon.
02/27/23 First Quarter Moon.
03/01/23 Appulse of Venus and Jupiter. — Separated by 0.5°.
03/02/23 Appulse of Mercury and Saturn. — Separated by 1.1°.
03/07/23 Full Moon.
03/14/23 Last Quarter Moon.
03/15/23 Neptune at conjunction. — Passing behind the Sun.
03/16/23 Appulse of Mercury and Neptune. — Separated by 0.6°.
03/17/23 Mercury at superior conjunction. — Passing behind the Sun.
03/20/23 Earth at northward equinox. — Beginning of our Spring.
03/21/23 New Moon.
03/27/23 Appulse of Mercury and Jupiter. — Separated by 1.3°.
03/28/23 First Quarter Moon.
03/30/23 Appulse of Venus and Uranus. — Separated by 1.2°.

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Deep Sky

The winter Milky Way is now prominent in the sky.  There are many spectacular deep sky objects we can see now.  Starting with open clusters, we first have the Pleiades (Seven Sisters, M45) nearly in the middle of the sky.  Next to that, the Hyades cluster (C41) makes up the face of Taurus the bull.  Also nearby, the constellation of Auriga contains M36, M37, and M38, which are visible with binoculars.  We also have Perseus's Double Cluster (C14) still fairly high in the northwest, and the Beehive (Praesepe, M44) up in the east.

This is not a good time of year to see globular clusters, as most of them are concentrated in the summer sky.  The brightest one we can see now is M79 below Orion in Lepus the hare, but it is nearly 8th magnitude.

For nebulae, we have the spectacular Orion Nebula (M42) now prominent in the south. This is the closest star-forming region to our solar system.  We also have some good planetary nebulae, which come from dying stars.  The Blue Snowball (C22) in Andromeda is towards the west, the Eskimo (C39) in Gemini is high in the east, and the Owl (M97) in Ursa Major is low in the northeast.

And now the galaxies:  Our neighbor the Andromeda Galaxy (M31) is now heading towards the west and is visible on dark nights with the naked eye.  Also nearby is the Triangulum Galaxy (M33), visible with binoculars.  In Ursa Major to the northeast we have Bode's Galaxy (M81) and the Cigar Galaxy (M82), close enough to be seen together in a low-power telescope.

Interesting Deep Sky Objects to Observe during February and March (during observatory hours)

Designation Name Apparent Magnitude Apparent Size Distance
(light-years)
Type
Messier 45 Pleiades 1.6 110' 440 open cluster
Messier 31 Andromeda Galaxy 3.4 3° x 1° 2,900,000 spiral galaxy
Messier 44 Beehive Cluster 3.7 95' 577 open cluster
Messier 42 Orion Nebula 4 85' x 60' 1400-1600 diffuse nebula
Messier 33 Triangulum Galaxy 5.7 67' x 42' 3,000,000 spiral galaxy
Messier 3 (in Canes Venatici) 6.2 18' 34,000 globular cluster
Messier 81 Bode's Galaxy 8.5 21' 1,200,000 spiral galaxy
NGC 3242 Ghost of Jupiter 8.6 25" 1400 planetary nebula
Messier 82 Cigar Galaxy 9.5 14' 1,200,000 galaxy

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Frequently Asked Questions

How can we identify planets in the night sky?

Planets are fun and easy objects to look at through a telescope, but how do we know where to point?  Well, there are four main factors you can consider when looking for planets.

First is location.  Planets lie along a path in the sky known as the ecliptic.  Our solar system is very flat, and so they all appear to line up with each other from our point of view here on Earth.  The Sun and Moon are the two easiest objects to spot on the ecliptic, so if you know where those are, you have a good idea where the planets are going to be.  This is also where the zodiac constellations are, so if you are familiar with those, they can help you find the planets in the sky.

Next is brightness.  Planets (most of them at least) are some of the brightest objects we can see in our sky.  At their brightest, Mercury, Venus, Mars, and Jupiter can all be brighter than the brightest star Sirius.  Saturn at its brightest is only slightly dimmer than the second-brightest star Canopus.  So if you see something very bright near the ecliptic, chances are it is a planet.

Third is twinkling, also known as scintillation.  You know the song "Twinkle, Twinkle, Little Star", right?  It's not "Twinkle, Twinkle, Little Planet" for a reason.  As light comes into our atmosphere, turbulence causes it to flicker and dance.  A similar effect can be seen if you try to look at something at the bottom of a swimming pool.  If the source is tiny the effect is much more noticeable.  Through a telescope, even the nearest stars look like pinpoints to us, while the planets look like round disks.  This is because the planets are so much closer to us than any stars (other than the Sun of course).  Since their light is spread over a larger angle, the random effect of turbulence kind of cancels itself out and the planets appear to have a much steadier image.

Finally is motion.  You wouldn't be able to see any motion on a single night, but if you watch a planet over several nights (or even months) you might notice its position moving slowly against the background stars.  Yes, stars are technically moving too, but it would take thousands of years to make a noticeable difference in our sky.  But if you notice something is in a slightly different position from where it was a few nights ago, you might be looking at a planet.

If you have any questions you'd like me to answer in the next issue of SWG, please let me know.  I'm also happy to take suggestions or comments, and also pictures if you'd like to send them.  Happy viewing!

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Date of publication: 2023