The Pleiades (M45) Credit: Warren Keller
You know, after decades of pointing optics towards the sky, I consider me a well -informed observer. But while I was looking for the Pleiades a few months ago, I was surprised to learn that it was not the brighter stars cluster. And there were other surprises when I started comparing the general brightness of deep objects. For example, you might think that some easy winners would be the galaxies, which host billions of stars, but when I started to classify objects, only two galaxies did the top 25; Most of the objectives I have listed here are open clusters, star associations (scarcely populated open clusters) or asterisms.
Even if you may have looked closely to many of these goals before, you probably didn’t really observe them, looking beyond the forest for the weakest trees. Well, here’s your opportunity to take a step back and take the maximum light that the night sky has to offer.
Top of the pile
You may have guessed that the brightest object is the first galaxy on our list, the Great Magellanic cloud. At the turn of the border between the Dorado and Mensa constellations, it lights up a great size 0.1. And it is enormous: it covers an area greater than 9 ° of 11 °, or 400 times that of the full moon. Visible just south of the latitude of 20 ° to the north, the large magellanic cloud is better seen in the summer of the southern hemisphere (i.e. from December to February).
Second in the list is the open cluster Hyades and the nearby bright star Aldebaran (Alpha [α] Tauri). Together, they form an V group that marks the bull’s head. Although Aldebaran is counted as part of the Hyades, giving that group a great size 0.5, it is not part of the star cluster in reality there is almost 90 light years closer to us.
The deepest refrigerated sky object, which shines with magnitude 0.6, is collinder 70, an open cluster of about 100 hot stars. You may know with the most famous name of its three brightest members: The Orion belt. The belt is probably linked to the great ladle as the best known asterism in the night sky. But also through modest binoculars, the belt seems embroidered with a series of brighter and still bright companions.
Linked for third place on our list – also to magnitude 0.6 – is Collinder 173An open cluster melted (6th at the level) on the border between puppies and sailing. It is located about 1,400 light years away. Such a brilliant cluster should be easy to find, but it is difficult to identify members. Watch about 10 ° North-Northwest of Alsephina (Delta [δ] Velorum) and use binoculars 7 × 50 to frame it better.
Get to n. 5 with a size of 1.0 is the Scorpius Superior Association – an association rather than an official open cluster. Also called Cluster Antares, this 8th group at 8 ° surrounds the Stella Antas (Alpha Scorpii). Even the 7 × 50 binoculars with low power and wide cannot admire the entire group, so you will have to scan. You have probably seen these stars – the four front stars of Scorpius (β, δ, π, ρ) plus some others – many times, but perhaps I have never known that they were an association.
No. 6 on our list is the Alpha Cluster Persei, An open cluster that takes its name from its brightest member: magnitude 1.8 Mirfak (Alpha Persei). With a total size of 1.2 and a diameter of 6 °, it is easy to find and small enough to frame through 7 × 50 binoculars.
One of the most famous objects in this list, arriving in seventh place with a size of 1.6, is the Pleiadi (M45). In ancient times, this star model was so appreciated that many Greek philosophers considered it a separate constellation. Often you call seven sisters, a reference to a Greek myth, observers with the most sharp eyes can identify only six stars. High quality binoculars will increase that number to 50.
The eighth deep-product object is the Coma Star Cluster (Melotte 111), an open cluster that is located about 280 light years. Although its combined size is 1.8, that brightness is widespread in a 4½ ° wide area. The cluster contains less than 100 members and only a dozen of about are quite bright to see without optics. So use binoculars.
THE Southern Pleiades (IC 2602), a splendid open cluster surrounding the star Theta (θ) careee, is not to ninth on our list. It lights up of size 1.9 and extends over almost 1st. The binoculars that enlarge 10x or more do a good job by revealing this cluster, but if you have an eye in your telescope that has a 1st or more visual field, you are ready for a real surprise.
Second class
The tenth object on our list is the first to fall into the 2nd magnitude class. Is the Cluster P puppis (Collinder 135), which is centered around the magnitude 2.7 stars Ahadi (PI [π] Puppies). This star is located alone about 7 ° to the east of the average point of a line between the two brightest stars of the sky, Sirius (Alpha Canis Majors) and Canopus (Alpha Carinae). The cluster has a total size of 2.1, but more is the main for two reasons. First of all, it is the brightest star and, second, it is a red supergiant. All the other stars in the visual field are blue.
THE Cluster Overcron Velorum (IC 2391) Registers in magnitude 2.5 and is linked to the 11th on our list. This is not a small object, which measures just under a degree of diameter. This means that its area is more than double that of the full moon. The best views through any area will arrive when you use an eye that gives a 1st visual field.
The next object is what I am sure you have seen hundreds of times, but it may not have known that it was an open cluster. THE Lost jewel of OrionOtherwise known as NGC 1980, it shines with magnitude 2.5. It focuses on the magnitude 2.8 stars Iota (ι) Orionis and is part of the hunter’s sword. It is located just south of the Orion nebula (M42).
Another couple binds to Lucky 13, with the first open collinder 121 cluster in Canis Major. You will find it less than ½ ° south of Omarron1 (ο1) Canis Majoris. It lights up well to magnitude 2.6 and has a diameter of 30 ‘. It is about 3,500 light years away, but there is another group of stars more widely spread only 2,000 distant light years, between Collinder 121 And us. No problem, though. The closest stars will appear simply as field stars through your eyepiece. Lented with Col 121 is the open cluster NGC 6231 in Scorpius. Often called Scorpio for children, it also lights up with magnitude 2.6 and extends 15 ‘. Together with Zeta (ister) and Mu (μ) Scorpii, forms an asterism the British astronomer Sir John Herschel called False Comet. This called it for two reasons: 1) the group seems to be a comet; and 2) Herschel, who had traveled on a ship in South Africa to see the southern sky, landed in False Bay.
The other galaxy on our list, and the object of the fifteenth deep, is the Small cloud of Magellanicawhich is mainly found in Tucana with a small part in Hydrus. Its combined brightness is equivalent to a magnitude 2,7 star. It is located about 200,000 light years away, but still covers a slightly larger than 3rd larger sky area. This is a space more than 70 times larger than the full moon.
THE Lambda Orionis ClusteR in Orion makes our list at number 16. It is easy to find because its brightest member is Meissa (Lambda [λ] Orionis), the star that marks Orione’s head. The cluster shines with magnitude 2.8 and extends a little less than 1 °.
Legate for 16th place, also in magnitude 2.8, is an open cluster NGC 2451 In Puppis, sometimes called a pungent scorpion cluster. In the 90s, astronomers discovered that this object was a combination of two unrelated open clusters (now known as NGC 2451a and NGC 2451b) which are aligned from our point of view.
Bottom of the upper part
Eighteenth on our list is an open cluster Collinder 65 In Orion. In fact, it is found to the north in that possible constellation, right on the border with Toro. It lights up with magnitude 3.0 and is large: it boasts a diameter of 3½ °. The large field binoculars will show the cluster better.
Linked to 18th place is the Cluster Firefly Party (NGC 3532) in cute. It indicates a 4 -inch area to this beauty and you will understand how it obtained its extravagant name. Search it about 4.7 ° South-Southwest of the 4th Magnitude PI Centaurus. Its brightness of third magnitude spreads on almost a diameter of 1 °, so even if you see it as a patch blurred without optical help, a telescope will bring out its best characteristics.
Also linked to 18th place is Melotte 186An open cluster dissolved in Ofiuchus. And when I say loose, I mean. Although the combined brightness of its stars is equal to magnitude 3.0, the diameter of this group is a huge 4th. Use the binoculars or scan with the lowest eye in your telescope to view the entire group.
You probably saw n. 21 on our list. Is the Cluster AlveareAlso known as Praesepe, M44, NGC 2632 and more. This open cluster is located in the center of cancer the crab. Observers with sharp eyes have no problems seeing M44 with naked eyes, even if there is a little widespread moon. It lights up with magnitude 3.1 and has a width of more than three full moons.
The 22 ° object is located near the bottom of the figure of Scorpius. His Tolomeo’s cluster (M7), and is the southernmost object. This open cluster is an easy capture from naked eye, which shines with magnitude 3.3, even if it is centered in the Milky Way.
Collinder 140An open cluster in Canis Major, shines 23 on our list. It lights up of size 3.5 and extends 42 ‘. To find it, look 3rd south of Audra (Eta [η] Canis Majoris). Through an 8 -inch low -power scope you should be able to count about three dozens of member stars.
Sharing the 23rd slot is Trumpler 37An open cluster in Cefeo. Long -date amateur astronomers, in particular the astroimager, recognize it as the cluster in the heart of the nebula of the elephant trunk (IC 1396). A 8 -inch area will reveal about 50 members of members.
Object 25 and final on our list is Collinder 132An open cluster in Canis Major. To find it, do not look for 3rd south -ovest of Audra. It lights up with magnitude 3.6 and spreads on an area of 1½ ° in front.
Ok, I lied. Collinder 132 is not the last object because another group of stars is linked with it in the brightness: the CoathangerA vulpecula asterism. This object transports a variety of names, including Alla Sufi’s cluster, Brocchi’s cluster and Collinder 399. Although it is a bagion loose in the bare eyes, 7 power or greater binoculars show it as a line of stars of 1ulation with a separate curve on the southern side, giving it the appearance of a meeting.
And you’re done. The next time you go out in the darkness, take a minute to appreciate these not so hidden gems and bask in all their glorious light.
