The radiant companions of Orion
You probably know this too: the view out of the window into the wintry night always finds the same target - the great hunter Orion, who immediately attracts our attention, regardless of whether he crosses the meridian in the evening or himself toward the western horizon at midnight. On the star map you can immediately see that Orion does not wander alone. He and his friends-Taurus, Carter, Gemini, and Big Dog and Little Dog-can't be missed in the sky.
Orion has a bit of everything: the red supergiant Betelgeuse, which is about twenty times more massive than our Sun. The hot, blue-white supergiant Rigel, on the other hand, has only appeared for less than 100 million years. Mintaka, an intensely hot blue giant in the upper right of Orion's Belt, hasn't kept us company for 50 million years. But the small "Trapeze", an easy telescopic target at the heart of the Orion Nebula M42, outshines them all. His quartet consists of immensely hot stars that may be just 10,000 years "Image"! alt="
The Orion Nebula itself, at 4th magnitude, is the prime example of an emission nebula, an expansive cloud of hydrogen gas ionized by the young, hot stars within it. Looking at this nebula, we see a stellar cradle embedding not just new suns, but entire solar systems.
Planets in February
Venus is one of two evening stars decorating our sky at dawn this month. Your flare is -3, 9th magnitude. In the middle of the month, at sunset, it is a whopping twenty degrees above the southwestern horizon and takes more than two hours to set. In the telescope, however, the planet still doesn't look much better. The 11 arc second disk is almost full, but cloud structure should be barely visible. Look out for the crescent Moon, just a degree and a half from Venus on February 19.
Mercury has broken out of its upper conjunction and hangs below Venus in the haze of the horizon. The planet reaches a remarkable -1. Size, but its tiny disk, less than six arc seconds across, makes it worth targeting after the first few days of February as it gradually gains altitude above the west-southwest horizon. On the 7th it reaches its greatest angular distance from the Sun, the eastern elongation. Then at sunset he is 15 degrees above the horizon, only to dive an hour and a half later. Let Venus guide you: it appears to the upper left, at seven degrees about one binoculars field of view away. If half an hour later the first stars come out like Sadalmelik in Aquarius, you will hardly be able to miss Mercury. It's definitely worth a look through the telescope now. Its disc looks like a miniature first quarter moon. It then decreases rapidly until mid-February, but the height of its crescent grows to almost ten arc seconds, almost matching the dimensions of Venus.
Saturn moves backwards in the constellation Leo – experts call it retrograde – i.e. in the opposite direction compared to the fixed starry sky and thus westwards away from Regulus. It gets progressively bigger and brighter as it moves towards the opposition. It reaches it on February 10th, then rises at sunset and remains visible all night. Saturn is second to none in the telescope. Its incomparable rings have been "closing" since 2003. They are currently still tilted 14 degrees, presenting their southern side, and appearing 45 arc seconds wide. A small telescope shows the broad, bright B ring on the inside, the thinner A ring on the outside, and the razor-thin Cassini division in between. Finally, you can discover five or six of Saturn's 56 known moons. At 8th magnitude, Titan is the brightest and a surefire catch in any binocular.
Jupiter appears just before dawn - in time for breakfast. Radiating at -1.8 mag, the giant ball of gas is easily seen in the Ophiuchus, a few degrees above the 1st magnitude bright Scorpio main star Antares.
Mars glimmers at only 1.8 magnitude and just east of the Jupiter-Antares tandem in the horizon haze to pick out. How fitting that Antares, translated Antimars, surpasses him in brightness at this time. If you are struggling to find Mars, the moon that falls on the 14th will help you. February is a little further west.
The Moon begins February in the constellation of Cancer and moves one day after full moon, on the night of the 3rd, not half a degree above Saturn. A super motive! The evening twilight of February 18th and 19th also promises to be impressive, when a two- and three-day-old crescent rises near Mercury and Venus. Incidentally, on the 18th, the moonset is followed by an occultation of Uranus. If you're going on a trip to Spain or Portugal, don't forget your binoculars. Those who stayed at home can console themselves with a partial occultation of the Pleiades star cluster (M 45): At the change of date to February 24, the moon moves in front of Taygeta and Maja. The spectacle lasts 54 and 48 minutes, until the stars reappear on the "sickle side". © astronomy today
