Skywatcher's Guide written by: Lucas Snyder (Flandrau Planetarium Specialist)
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Stars and Constellations
In October, only a small portion of the spring sky is still visible at the beginning of the night. The Big Dipper (Ursa Major) is low in the north-northwest. As always, the last two stars in the bowl point to Polaris, our north star, in the Little Dipper (Ursa Minor). You can also still follow the arc of the handle of the Big Dipper to Arcturus, the bright star in Boötes, now low in the west-northwest. The summer constellations are also visible for a good portion of the night, starting the night in the middle of the sky. The Summer Triangle is almost directly overhead, with Vega closest to the west-northwest, Deneb closest to the northeast, and Altair closest to the south. The summer Milky Way is still prominently streaking across the sky, cutting from the northeast to the southwest. Scorpius with the bright star Antares is now getting low in the southwest, and the nearby "teapot" of Sagittarius in the south-southwest. The fall sky is now very prominent, taking up most of the eastern sky at the beginning of the night. The "W" of Cassiopeia is easy to spot in the northeast, with Perseus just below. The Great Square of Pegasus is up in the east, and Andromeda nearby in the east-northeast. There is also a fairly bright star called Fomalhaut in the southeast, though its constellation Piscis Austrinus is not easy to distinguish.
In November, all but a few of the spring stars are now gone, and the summer constellations are starting to get lower in the west. Deneb is the highest point of the Summer Triangle, with Vega below to the west, and Altair towards the southwest. The brightest part of the summer Milky Way is now gone, but a good portion of it is still easy to distinguish. Scorpius is now gone, but the "teapot" of Sagittarius is still above the horizon in the southwest. The fall sky is now a little higher, but still in the eastern half of the sky. We can now begin to see a few winter stars coming up along the eastern horizon, namely the bright Capella in the northeast and Aldebaran in the east-northeast. Also look for the Pleiades (aka the Seven Sisters or Subaru) star cluster just above Aldebaran.
Interesting Stars Visible in October and November (between 7 and 10 pm)
Name / Designation | Apparent Magnitude (lower = brighter) |
Distance (light-years) |
Notes |
---|---|---|---|
Arcturus | -0.05 | 36.7 | |
Vega | 0.03 | 25 | |
Capella | 0.08 | 42 | |
Rigel | 0.18 | 770 | |
Betelgeuse | 0.45 | 427 | |
Altair | 0.76 | 17 | |
Aldeberan | 0.87 | 65 | |
Pollux | 1.16 | 38 | |
Fomalhaut | 1.16 | 25 | |
Markab | 1.25 | 140 | |
Deneb | 1.25 | 3230 | |
Castor | 1.58 | 52 | |
Polaris | 1.97 | 431 | |
Alpheratz or Sirrah | 2.07 | 97 | |
Mirach | 2.07 | 199 | |
Algol | 2.09 | 93 | variable star |
Enif | 2.38 | 670 | |
Almak | 2.1 / 5.0 & 6.3 | 355 | triple star system w/ 64 yr orbit |
Albireo | 3.2 / 5.8 & 5.1 | 390 / 380 | possibly a triple star system |
Eta Cassiopeiae | 3.5 / 7.4 | 19 | 480 yr orbit |
Solar System
Mercury is visible near the west-southwestern horizon after sunset from mid-October to late November.
Venus is easily visible in the southwestern sky after sunset throughout October and November.
Mars is in Gemini, very high in the morning sky in early October and slowly moves toward the west and into Cancer until the end of November.
Jupiter is in Taurus, very high in the morning sky in early October, but gradually gets closer to the western horizon by the end of November.
Saturn is in Aquarius, starting the night in the east-southeast in early October but gradually making its way to the south by the end of November.
Jupiter Great Red Spot Transits visible during October and November (between 7 and 10 pm)
Note: The GRS is visible on the disk of Jupiter for 50 minutes before and after meridian transit time.
Date | Meridian Transit Time |
---|---|
10/29/24 | 09:55 PM |
11/03/24 | 09:02 PM |
11/10/24 | 09:47 PM |
11/15/24 | 08:54 PM |
11/20/24 | 08:01 PM |
11/22/24 | 09:39 PM |
11/25/24 | 07:08 PM |
11/27/24 | 08:46 PM |
Calendar of Night Sky Events
Date | Event |
---|---|
10/02/24 | New Moon and Annular Solar Eclipse. — Not visible from Tucson. |
10/10/24 | First Quarter Moon. |
10/17/24 | Full Moon. |
10/20/24 | Peak of Orionids meteor shower. |
10/24/24 | Last Quarter Moon. |
11/01/24 | New Moon. |
11/04/24 | Peak of Southern Taurids meteor shower. |
11/08/24 | First Quarter Moon. |
11/15/24 | Full Moon. |
10/16/24 | Mercury at greatest eastern elongation. — visible in the evening sky. |
11/16/24 | Uranus at opposition. — Best time to see this gas giant. |
11/17/24 | Peak of Leonids meteor shower. |
11/22/24 | Last Quarter Moon. |
11/30/24 | New Moon. |
Deep Sky
There are many deep sky objects we can see since the summer Milky Way is high in the sky. There are many open star clusters that can be seen with only binoculars scanning this part of the sky. For example we have the Butterfly Cluster (M6) and Ptolemy's Cluster (M7) near the tail of Scorpius. Further north there is the Wild Duck Cluster (M11) in the faint constellation of Scutum between Sagittarius and Aquila. There is also the asterism of the Coathanger between Aquila and Cygnus in the fainter constellation of Vulpecula. Next, heading towards the west we can see the Coma Star Cluster in the constellation of Coma Berenices, which is even visible naked-eye. The Pleiades (M45) will be visible later in the night, after midnight.
There are a several globular clusters we can see as well, as the center of our galaxy is the highest it gets for the year. Near the bright star Antares in Scorpius lies the globular cluster M4. In Sagittarius we also have the Teapot Cluster (M22). Of course we have the famous Hercules globular (M13) high in the east. Also, M15 is visible in the east near the head of Pegasus.
For nebulae, we have several in the plane of the galaxy, one of which is the Swan Nebula (M17) in Sagittarius, also known as the Omega Nebula. There is also the Lagoon Nebula (M8) nearby and the North America Nebula (C20) further north in Cygnus. For planetary nebulae we have the Ring Nebula (M57) in Lyra, the Dumbell Nebula (M27) in Vulpecula, and the Blue Snowball (C22) in Andromeda.
And now the galaxies: Although the Big Dipper is getting lower in the sky, you may still be able to find some of the galaxies in this part of the sky. We have the Whirlpool Galaxy (M51) and the Pinwheel Galaxy (M101) near the handle, and the Cigar Galaxy (M82) and Bode's Galaxy (M81) near the bowl. The spectacular Andromeda Galaxy (M31) is now coming up in the northeast, along with the nearby Triangulum Galaxy (M33).
Interesting Deep Sky Objects to Observe during October and November (between 7 and 10 pm)
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 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 |
NGC 7293 | Helix Nebula | 7.3 | 16' | 450 | planetary nebula |
Messier 27 | Dumbbell Nebula | 7.4 | 8' × 6' | 1,250 | planetary nebula |
NGC 7009 | Saturn Nebula | 8 | 36" | 2,400 | planetary nebula |
Messier 81 | Bode's Galaxy | 8.5 | 21' | 1,200,000 | spiral galaxy |
Messier 57 | Ring Nebula | 8.8 | 1' | 2,300 | planetary nebula |
Messier 82 | Cigar Galaxy | 9.5 | 14' | 1,200,000 | galaxy |
Frequently Asked Questions
Is there life on other planets?
This is actually a very common question, and I’m surprised I haven’t talked about it yet in the SWG. It can be a touchy subject because it brings up thoughts of little green men and alien abductions. I’ll start by saying I don’t believe aliens have visited Earth, but who knows? I could be proven wrong about that some day.
For thousands of years, people have speculated that there could be extraterrestrial life, and sometimes its existence was even assumed to be commonplace in our universe. Even as recently as the early 1900s people were making maps of civilizations on other planets (e.g. Percival Lowell’s map of Mars). We were actually a little disappointed when we sent spacecraft there and didn’t find any life. But that hasn’t kept us from searching.
Beginning around 1960, Frank Drake and other scientists began to consider all the factors that would go into determining our chances of finding extraterrestrial life. These factors include how many stars have planets, how many planets are habitable, how many habitable planets develop life, how many species create technology that could be detectable, and how long civilizations would transmit signals. Now, some of these factors would have to be educated guesses at best, but we can start to make estimates of how many other civilizations might be out there. Depending on how conservative we are with the various factors, the Drake equation yields results anywhere from less than one civilization in our galaxy (meaning we are alone) to over 10 million.
In addition to intelligent civilizations, we have been looking for evidence of past or present microbial life here within our solar system. We believe Mars may have been habitable in the past, so that’s one place we’ve been searching. We’re also beginning to investigate the icy moons of Jupiter and Saturn to see if they might have life hidden below the surface. If we find extraterrestrial life in our own backyard, so to speak, that is a good sign we may be able to find it elsewhere too.
While we haven’t found life yet anywhere but on our own planet, the universe is big enough that even if life is rare, there is a good chance that it is somewhere out there. It may just be a matter of time until we find it. It will definitely be exciting news when we make that discovery.
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!
Date of publication: 2024