I finally did it! I was finally able to go stargazing in October. This was the first October since I started stargazing almost three years ago when there were clear nights when I was free and able to go out and observe the sky. My pictures are below. Most of them have never been included in a blog entry before. Some of them are “new and improved”. I have even included some Halloween specials!
Arabian Astronomy
I include images of a few stars in each of my blog entries. Have you noticed that many of those stars have Arabic names? This is because Arabs have a rich history of astronomical study. The pre-Islamic Arabs relied upon empirical observations. These were based on the rising and setting of particular stars. They named the stars that were important to them. Medieval Islamic astronomy comprises the astronomical developments made in the Islamic world, particularly during the Islamic Golden Age (9th–13th centuries), and mostly written in the Arabic language.
Islamic astronomy played a significant role in the revival of ancient astronomy following the loss of knowledge during the early medieval period, notably with the production of Latin translations of Arabic works during the 12th century. The Arab world maintained a lot of knowledge lost to Western cultures during the Dark Ages. This included astronomical and mathematical knowledge. Of course, they contributed original scholarship as well. Islamic astronomy also had an influence on Chinese astronomy.
A significant number of stars in the sky, such as Aldebaran, Altair and Deneb, and astronomical terms such as alidade, azimuth, and nadir, are still referred to by their Arabic names. A large corpus of literature from Islamic astronomy remains today, numbering approximately 10,000 manuscripts.
Here is a list of stars from my blog entries that have Arabic names along with what those names mean.
Star Name Meaning
Alcor the Faint One
Alderamin the Right Arm (of Cepheus)
Alioth The black horse "John"
Altair the Flying (Eagle)
Betelgeuse hand of the Central One
Deneb Tail of the hen
Eltanin the Great Serpent
Hamal (head of) the Ram
Markab the Saddle (of the Horse)
Mirach the Loins / Loincloth
Mizar the Apron
Rasalhague Head of the Snake-man
Rigel Foot of the Giant
Sadalsuud Luck of Lucks
Vega the Falling Eagle
Zubenelhakrabi Claws (of the scorpion)
Planets
This is about the best picture of Jupiter that I am going to get with my current telescope and software. This picture was taken about two weeks before the planet reached opposition. It is noticeably bigger and brighter than the picture of Jupiter that I included in my August blog entry. You can clearly see the red bands on the planet and even a couple of storms. The storms look like dark smudges on the planet.
I included this picture of Saturn because it was a couple of months past opposition when this photo was taken. It is noticeably smaller than the picture in my August blog post.
The Jupiter and Saturn pictures show how important planetary position is to their observation from Earth.
Uranus was about a month from opposition when I took this photo. It is bigger than in my other photos but not by much. Uranus is so much farther away than the other two planets that its position relative to Earth is less significant.
Star Clusters
I like viewing star clusters and including them in my blog entries. I think these diverse star formations are fascinating. There are so many different configurations. There are also a lot of star clusters that are Messier objects and I want to view all of the Messier objects. There are 110 of them and I have now seen exactly half of them; 55 objects. Astronomers have contests to see who can view all of the Messier objects in the least amount of time. I am not interested in a speed contest but I do want to see them all over time.
Messier 2 or M2 (also designated NGC 7089) is a globular cluster in the constellation Aquarius, five degrees north of the star Beta Aquarii. It is one of the largest known globular clusters. M2 was discovered by the French astronomer Jean-Dominique Maraldi in 1746 while observing a comet with Jacques Cassini. Charles Messier rediscovered it in 1760, but thought that it is a nebula without any stars associated with it. William Herschel, in 1783, was the first to resolve individual stars in the cluster.
My telescope is good enough to see individual stars on the outside of the M2 cluster but the center of the cluster appears to be one super giant star because there are so many stars closely packed together. This is what makes the cluster so interesting to me.
M2 is, under extremely good conditions, just visible to the naked eye. M2 is about 55,000 light-years distant from Earth. At 175 light-years in diameter, it is one of the larger globular clusters known. The cluster is rich, compact, and significantly elliptical. It is 12.5 billion years old and one of the older globular clusters associated with the Milky Way galaxy. M2 contains about 150,000 stars, including 21 known variable stars. Its brightest stars are red and yellow giant stars.
Messier 34 (also known as M34 or NGC 1039) is a large and relatively nearby open cluster in Perseus. It was probably discovered by Giovanni Batista Hodierna before 1654 and included by Charles Messier in his catalog of comet-like objects in 1764. Messier described it as, "A cluster of small stars a little below the parallel of γ (Andromedae). In an ordinary telescope of 3 feet one can distinguish the stars."
It is about 470 parsecs (1,500 ly) away. The cluster has about 400 stars. It spans about 35′ on the sky which translates to a true radius of 7.5 light years. The cluster is just visible to the naked eye in very dark conditions, well away from city lights. It is possible to see it in binoculars when light pollution is low. The age of this cluster lies between the ages of the Pleiades open cluster at 100 million years and the Hyades open cluster at 800 million years. Its probable age is 200–250 million years old.
Messier 38 or M38, also known as NGC 1912 or Starfish Cluster, is an open cluster of stars in the constellation of Auriga. It was discovered by Giovanni Batista Hodierna before 1654 and independently found by Le Gentil in 1749. The open clusters M36 and M37, also discovered by Hodierna, are often grouped together with M38. Distance is about 1.066 kpc (3,480 ly) away from Earth. The open cluster NGC 1907 lies nearby in the sky, but the two are most likely just experiencing a fly-by, having originated in different parts of the galaxy. The cluster's brightest stars form a pattern resembling the Greek letter Pi or, according to Webb, an "oblique cross".
At its distance of 1066 pc., its angular diameter of about 20 arc minutes corresponds to about 4.0 parsecs (13 light years), similar to that of its more distant neighbor M37. It is of intermediate age at about 290 million years. From the population of about 100 stars, this open cluster features a prominent yellow giant with the apparent magnitude +7.9 and spectral type G0 as its brightest member. This corresponds to an absolute magnitude of -1.5, or a luminosity of 900 Suns. For comparison, the Sun would appear as a faint magnitude +15.3 star from the distance of M38.
I just like the interesting combination of blue / white stars and red / yellow stars that make up the cluster.
Messier 71 (also known as M71 or NGC 6838) is a globular cluster in the small northern constellation Sagitta, the Arrow. It was discovered by Philippe Loys de Chéseaux in 1745 and included by Charles Messier in his catalog of non-comet-like objects in 1780. It was also noted by Koehler at Dresden around 1775. This star cluster is about 13,000 light years away from Earth and spans 27 light-years (8 pc). The irregular variable star Z Sagittae is a member.
NGC 6819 is an open cluster (commonly known as an "open star cluster") located 7,200 light years away in the Cygnus the Swan constellation. It was discovered by Caroline Herschel on 12 May 1784. Situated on the boundary of Cygnus and Lyra, NGC 6819 contains roughly two dozen stars of magnitude 10 to 12, with many more lower magnitude members. The age of NGC 6819 is estimated here to be ~ 2.5 ± 0.5 Gyr.
Nebulae
The Skull Nebula is the first of the Halloween specials in this blog entry. Unfortunately, this nebula does not look like much of a Skull in visible light. Be that as it may, the two bright stars in the nebula are supposed to be the skull’s eyes.
NGC 246 (also known as the Skull Nebula or Caldwell 56) is a planetary nebula in the constellation Cetus the whale. It is the first known planetary nebula to have a hierarchical triple star system at its center. The nebula and the stars associated with it are listed in several catalogs, as summarized by the SIMBAD database. NGC 246 was discovered by William Herschel in 1785. The nebula is roughly 1,600 light-years away. NGC 246's central star is the 12th magnitude white dwarf HIP 3678 A.
NGC 246 is not to be confused with the Rosette Nebula (NGC 2337), which is also referred to as the "Skull." Among some amateur astronomers, NGC 246 is known as the "Pac-Man Nebula" because of the arrangement of its central stars and the surrounding star field.
Galaxies
NGC 7479 is the second of my Halloween specials in this blog entry and proof that not all things Halloween have to be scary! NGC 7479 is affectionately dubbed the Superman Galaxy due to its distinctive ‘S’ shape. This cosmic superhero showcases its stunning, nearly symmetrical spiral arms, making it a heroic sight in the night sky. Also known as the Propeller Galaxy, it’s perfect for thrill-seeking stargazers in both hemispheres.
NGC 7479 (also known as Caldwell 44) is a barred spiral galaxy about 105 million light-years away in the constellation Pegasus the winged horse. William Herschel discovered it in 1784. NGC 7479 is also recognized as a Seyfert galaxy and a LINER undergoing starburst activity not only on the nucleus and the outer arms, but also across the bar of the galaxy, where most of the stars were formed in the last 100 million years. Polarization studies of this galaxy indicate that it recently underwent a minor merger and that it is unique in the radio continuum, with arms opening in a direction opposite to the optical arms. This feature, along with the asymmetrical arms of the galaxy and the intense star formation activity are attributed to a merger with a smaller galaxy. This galaxy is similar in both size and morphology to the barred spiral NGC 1300.
NGC 777 is an elliptical galaxy in the constellation of Triangulum. It was discovered by William Herschel on September 12, 1784. It has a weak active nucleus of type Seyfert 2 or LINER 2, implying that the central region is obscured. It may be an outlying member of galaxy cluster Abell 262. It is 189 million ly from us.
NGC 720 is an elliptical galaxy located in the constellation Cetus the whale. It is located at a distance of circa 80 million light years from Earth, which, given its apparent dimensions, means that NGC 720 is about 110,000 light years across. It was discovered by William Herschel on October 3, 1785. The galaxy is included in the Herschel 400 Catalogue. It lies about three and a half degrees south and slightly east from zeta Ceti.
Stars
My last Halloween treat is Mirach’s Ghost. It is an intriguing celestial duo located in the constellation Andromeda the princess. This ethereal pairing consists of Mirach, the brightest star in the constellation Andromeda the princess, and a faint, ghostly dwarf galaxy named NGC 404. Take a dark October night to gaze upon Mirach and catch a glimpse of its spectral companion! You can see the fuzzy-looking Mirach’s Ghost, NGC 404, above the star and to the left!
Beta Andromedae, Latinized from β Andromedae, and officially named Mirach is a prominent star in the northern constellation of Andromeda. It is northeast of the Great Square of Pegasus and is potentially visible to all observers north of latitude 54° S. It is commonly used by stargazers to find the Andromeda Galaxy. The galaxy NGC 404, also known as Mirach's Ghost, is seven arcminutes away from Mirach.
This star has an apparent visual magnitude of around 2.05, varying between 2.01 and 2.10, which at times makes it the brightest star in the constellation. Based upon parallax measurements, it is roughly 197 light-years (60 parsecs) from the Sun. Beta Andromedae is a single red giant with a stellar classification of M0 III.
NGC 404 is a dwarf lenticular galaxy located about 10 million light years away in the constellation Andromeda. It was discovered by William Herschel in 1784, and is visible through small telescopes. NGC 404 lies just beyond the Local Group and does not appear gravitationally bound to it. It is located within 7 arc-minutes of second magnitude star Mirach thereby granting it the nickname "Mirach's Ghost".
Bellatrix is the third-brightest star in the constellation of Orion the hunter, positioned 5° west of the red supergiant Betelgeuse (Alpha Orionis). It has the Bayer designation γ Orionis, which is Latinized to Gamma Orionis. With a slightly variable magnitude of around 1.6, it is typically the 25th-brightest star in the night sky. Located at a distance of 250±10 light-years from the Sun, it is a blue giant star around 7.7 times as massive as the sun with 5.75 times its diameter. The traditional name Bellatrix is from the Latin bellātrix "female warrior".
Hamal designated Alpha Arietis (α Arietis, abbreviated Alpha Ari, α Ari), is the brightest star in the northern zodiacal constellation of Aries the ram. With an apparent visual magnitude of 2.0, it is the 50th-brightest star in the night sky. Based upon parallax measurements made with the Hipparcos astrometry satellite, Hamal is about 65.8 light-years (20.2 parsecs) from Earth. It is a giant star that may host an orbiting planet with a mass greater than Jupiter. The traditional name Hamal (also written Hemal, Hamul, Ras Hammel) derives from the Arabic "head of the ram".
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