The months of October and November represent an exceptional period for comet lovers. There will be, in fact, well four comets to give show in heaven, C/2025 R2 (SWAN), C/2025 K1 (Atlas), 3i/Atlas and C/2025 A6 (Lemmon)with the latter, already renamed “Autumn Comet”, having the most high probability of being visible to the naked eye in the second half of October. It is a Extremely rare event That you can follow arm you with a good binoculars or a small telescope from skies as exempt as possible from light pollution. C/2025 R2 (SWAN), C/2025 K1 (Atlas), 3i/Atlas, in fact, are above the visibility threshold with the naked eye according to the data in possession of the astronomers. The presence of the Meteoric peak of the Orionids Which will take place between 20 and 23 October, just as C/2025 A6 (Lemmon) will reach the slightest distance from our planet. In this article we see together what will be the best moments to observe these celestial visitors.
What we will see in the October sky
The autumn comet C/2025 A6 (Lemmon)
Comet C/2025 A6 (Lemmon) it is the most promising of the four, given that the data available to astronomers provide that it will be Visible to the naked eyewith a magnitude of about 3.1, in conjunction with its transition to minimal distance from the earth (150 million km), October 21st. It is a comet with an almost hyperbolic orbit of a period over a thousand years, 1350 to be precise. The comet is currently located a 180 million km from the earth and shines already with magnitude of 7.6towards the constellation of the lynx. However, it is not yet visible in our latitudes, setting simultaneously in the sun. Over the next few days, the orbit of the comet will lead her to be more visible, setting more and more delayed than the sun. Starting from mid -October, the comet will enter the Best visibility windowpresenting itself with an angular separation from the sun equal to about 40 degrees at the time of Massimo approach to the land of 21 Octobermaking it visible for three hours after the sunset of the sun in the west/north-west direction.
At the time of the maximum approach of 21 October, the additional show will also contribute Meteoric swarm of the Orionids. The latter, in fact, will have the peak between 20 and 23 October with a meteor rate of the order of 20 per hour. However, it is good to specify that the constellation of Orion, the radiant from which the meteors seem to come, will rise when the comet has now set under the horizon, so it will be difficult to spot the comet and a “falling star” produced by this swarm.
Comet C/2025 R2 (SWAN)
The second comet in order of brightness is C/2025 R2 (SWAN)identified thanks to the SWAN tool of the Soho telescope. The comet passed Perdielio on September 12 and is currently very difficult to spot in our latitudes (magnitude 6.7), since extremely low on the west horizon, setting about an hour after the sun. During the month of October comet will increase its angular distance from our star, thus also increasing the visibility window. C/2025 R2 (SWAN) will reach the minimum distance from the earth (about 40 million km) almost in conjunction with C/2025 A6 (Lemmon), the October 20th. However, at that point the estimates provide that the comet will have one magnitude equal to 7.3too weak therefore to be spotted with the naked eye, but brilliant enough to be identified with a good binoculars in the south-west direction. On October 20, the comet will have reached a considerable angular distance from the sun that will allow it to set almost six hours after our star. In those days we will therefore attend a fantastic show by Ben Two brilliant comets relatively close in the sky in the west/south-west direction.
Comete C/2025 K1 (Atlas) and 3i/Atlas
These two comets are the least bright of the quartet, with magnitudes that require the use of a telescope and dark skies in order to be sighted. Currently the two comets are found Angularly very close to C/2025 R2 (Swan) and several astrophotographers succeeded in the company of immortalize Between 19 and 21 September the two comets C/2025 R2 (SWAN) and C/2025 K1 (Atlas) in the same photograph in the company of the planet Mars. In the next few days the two comets will approach angularly more and more to the sun, returning to being visible towards the end of October a few hours before dawn. C/2025 k1 (Atlas) will reach the Maximum approach to the earth (60 million km) The November 24thwhile 3i/Atlas the December 19th (to 270 million km). Even at the point of maximum brightness, the two comets they will not exceed the tenth magnitudetherefore far away from being visible to the naked eye. The month of November represents the better time to observe thembeing visible for several hours before the sunrise. Even C/2025 k1 (Atlas) will be practically visible all night In the maximum approach of the November 24thshining with magnitude 11 in the constellation of the major bear.
We remember how 3i/Atlas jumped to the headlines to be the third object of interstellar origin never discovered by man. This comet that peculiar characteristics, different from those of the comets of our solar system, which brought astronomers such as Avi Loeb to speculate on the artificial origin of the object.
