Outreach

Astronomical events for the month of February 2025

We begin this month remembering a character who offered his life for science, the Italian astronomer Giordano Bruno. Two of the brightest objects in the night sky, the Moon and Jupiter, will be in conjunction, that is, they will share one of their celestial coordinates. We invite you to witness a meteor shower coming from the Centaurus constellation, despite not being one of the most abundant, they are recommended for their location. One of the nebulous objects visible to the naked eye is the open star cluster M44, but it will always be better to observe it with binoculars or a modest telescope. As a challenge for the month we propose the M81 group, in fact, the challenge is to locate M81 and M82 in the same field of view of a telescope, pointing it towards the constellation of the Big Dipper. And to close our anniversaries for the month of February, we list the lunar phases.

A martyr of knowledge

Filippo Bruno or Giordano Bruno was born near Naples, Italy in 1548. From an early age he showed great interest in theological knowledge and science. He soon excelled in both subjects, becoming a man of great wisdom in physics and astronomy, and of a wandering life, due to his convictions about religion. Giordano Bruno was a great professor, lecturer and disseminator of his scientific ideas about the diversity of worlds, in solar systems similar to ours, based on the heliocentric model, surpassing the theories of Nicolaus Copernicus, the theories of the movements that govern the stars and the infinity of space, and of the universe itself.

Unfortunately, his final destiny was not like that of Galileo, forced to renounce the heliocentric theory before a court of the Holy Inquisition and which, according to some historians, led him to pronounce the famous phrase "and yet it moves." For Giordano Bruno, the end was tragic; as he did not retract his thoughts, especially religious ones, he was executed on February 17, 1600.

Conjunction of bright objects

There are various coordinate systems to locate celestial objects; one of them is the equatorial system, which uses two coordinates: Right Ascension (RA) and Declination (DEC). Thus, we say that a celestial conjunction occurs when two or more objects share one of their coordinates, Right Ascension. On February 6 at 9:36 p.m., Central Mexico time, the Moon, our natural satellite, and the planet Jupiter (Jove for the Romans and Zeus for the Greeks) will be in conjunction. In addition to sharing its RA, the Moon will be located 5° 29´ arc minutes north of Jupiter, in the direction of the constellation Taurus.

The constellation “the bison man”

For the ancient Babylonians, the Centaurus constellation represented a man with the body of a bison and was associated with Shamash, the god of the Sun. Meanwhile, for the Greeks and Romans, the Centaurus constellation was associated with a type of creature half man and half horse, representing the centaur Chiron, who due to his wisdom was responsible for the formation of great heroes in the arts, medicine and hunting.

The Centaurus constellation covers a southern region of the celestial sphere, which can be seen by observers from a latitude of +25º, with a host of interesting celestial objects such as Ω Centaurus, one of the largest globular clusters in our galaxy; Centaurus A, one of the most famous galaxies; very bright stars, such as Alpha Centauri (-0.27) and Beta Centauri (+0.6), among many others.

In addition, it is associated with a meteor shower called the α-Centaurids, whose activity runs from January 28 to February 21, peaking on February 8, with at least 6 meteors per hour. The radiant is located in the direction of the Centaurus constellation. The object responsible for the shower has not been fully identified, but what is known is that the best time to observe them will be at dawn on the 8th, towards the southern part of the celestial sphere.

The only thing required to enjoy this meteor shower is patience, a good dark place, a hot drink and to be well covered; no optical instrument is required.

A thousand stars in the heart of Cancer

The open star cluster M44, also known as the Manger, Praesepe, Messier 44, NGC 2632 or Cr 189, is located in the direction of the constellation of Cancer, about 477 light years from Earth, contains more than a thousand stars, with ages ranging between 500 and 600 million years, and is easy to identify by its magnitude of 3.1, which makes it a bright and easy-to-observe deep field object. As a curious fact, the first exoplanets around stars similar to the Sun were discovered in this cluster that looks like a swarm of beehives and was considered by the Greeks and Romans to be a manger, where the donkeys that the gods Dionysus and Silenus rode in their battles against the Titans were fed and rested.

The M44 cluster will be well positioned for observation most of the night, towards the eastern part of the celestial sphere, with the naked eye in dark skies or with binoculars or small telescopes; obviously, with larger telescopes, greater details will be obtained.

The M81 group, a supercluster of galaxies in Virgo

Bode's galaxy, Bode Nebula, the Great Spiral, M81 or NGC 3031, is the first of the four objects originally discovered in 1774 by the German astronomer Johann Elert Bode, after whom it owes its name. It was catalogued by Charles Messier in 1781. Bode's galaxy is one of the best examples of the spiral design in a galaxy, as it is endowed with almost perfect arms arranged in a spiral towards its center, with at least 250 billion stars, which is located about 12 million light years from Earth, in the direction of the constellation of the Big Dipper, towards the north-northeast part of the celestial sphere.

Bode's galaxy has a satellite galaxy, the Cigar Galaxy or M82, both are the outstanding members of the group. M81 and M82 are very close to each other, at a distance of approximately 150,000 light years. With magnitudes 6.9 and 8.4, respectively. Binoculars or a small telescope are required to view this pair of galaxies that fall within the same field of view for most telescopes.

Phases of the Moon (Central Mexico time).

Contacts:

Dr. Agustín Márquez Limón (amarquez@inaoep.mx), Coordinación de Astrofísica-INAOE

M.C. Tania Martínez (astronomaplanetariokayok@gmail.com), Red de Planetarios del Estado de Quintana Roo

Dr. Raúl Mújica García (rmujica@inaoep.mx), Coordinación de Astrofísica-INAOE y Noche de las Estrellas