Comet at the end of the month
First of all, we would like to wish all visitors to our website a good start to the New Year. May it be filled with happiness and success.
After many years, we have the chance to see a comet with the naked eye again in January. The comet bears the prosaic name C/2022 E3 (ZTF). It was discovered with the help of a scientific facility at the Palomar Observatory in Los Angelas in March 2022. Its orbit will become circumpolar in the second half of January. Its brightness is expected to increase to the point where it will be visible to the naked eye by the end of the month.
On December 21, the sun was at the southernmost and, for us, lowest point of its orbit in the constellation of Sagittarius. At midday, it was just 17° above the horizon. We had the longest night and the shortest day. We already noticed at Christmas that things were slowly picking up again. This upward trend will continue in January.
On January 4, the Earth reaches its perihelion, the closest point of its orbit to the sun. The sun is then 147.1 million kilometers away from us. On January 20, it moves into the constellation of Capricorn.
The following table shows the most important dates of the sun for the 1st, 31st and for each Friday of the month. The end of twilight refers to the end of astronomical twilight. This is when the dark night begins, which is best suited for astronomical observations.
The moon had already reached its first quarter (waxing crescent) on December 30 of the previous year. Its light is initially perceived as very disturbing for deep-sky observations. It reaches its full moon position on January 7. It will then be in Gemini, i.e. very high in the sky, and will make deep-sky observations difficult or even impossible. If we can observe on the 6th, we will probably have to limit ourselves to the planets Jupiter and Mars.
The other moon phases are
January 15, third quarter (waning crescent moon)
January 21 New moon
January 28 first quarter (waxing crescent moon)
The second half of January is ideal for astronomical observations.
Planets
We will gradually have to say goodbye to some planets. But at least one replacement is already ready.
Mercury is in inferior conjunction with the Sun on January 7. It then stands between the Sun and Earth. The nimble planet closest to the sun is rapidly moving away from the sun. From January 20, we have a chance of seeing it in the morning sky just above the eastern horizon. However, it will fade very quickly in the increasing brightness.
Venus can be seen above the southwestern horizon shortly after sunset. In the last third of the month, the chances of seeing it are very good. In the following months, it will continue to expand its position as an evening star.
Mars was in opposition to the sun on December 8. It was 82.3 million kilometers away from us at the time. Its apparent diameter was 17 arc seconds and it shone with a brightness of -1.9 mag.
On January 12, it will end its opposition loop and become retrograde again, moving in front of the stars again in a westerly direction. And it is rapidly moving away from us.
The following table shows how Mars is constantly getting smaller. But we will be able to see it in the evening sky for several months.
| Day | Distance | apparent. Diameter | Helligk. likes |
| 1. | 95.5 million kilometers | 14.7 arc sec. | -1,2 |
| 15. | 109.7 million kilometers | 12.8 arc sec. | -0,8 |
| 31. | 130 million kilometers | 10.8 arc sec. | -0,3 |
Jupiter, the largest planet in the solar system, sets before midnight. In the first half of the month, it can still be observed with a telescope until 10 pm. In the second half of the month, conditions deteriorate noticeably after 9 pm. It is then too close to the horizon.
Saturn has largely receded from the evening sky. With good visibility to the south-western horizon, it can still be spotted at the beginning of nautical twilight. It no longer plays a role for our observatory.
Uranus can be found until after midnight. It is currently in Aries.
Neptune is an object of the first evening hours. After 10 pm it is too close to the southwest horizon.
Stars
The map, created with Stellarium, shows the sky on January 15, 2022 at 10 pm. In the western sky, Pegasus is approaching the horizon. Leo has already risen in the east, heralding the approach of spring. The sky is dominated by the winter constellations. Six bright stars have been selected as the cornerstones of the winter hexagon. They are Capella in Carthusia, Aldebaran in Taurus, Rigel in Orion, Sirius in the Great Dog, Prokyon in the Little Dog and Pollux in Gemini. The constellation of Unicorn lies largely within this hexagon without contributing a star.
Many deep-sky objects can be found within the constellations of the winter hexagon, such as the open star clusters M 35 (Gemini), 36, 37 and 38 (Fuhrmann), M 41 in the Great Dog, M 45 or Pleiades (Taurus) and M 50 (Unicorn). Taurus also contains M 1, a nebulous object that inspired Charles Messier to compile his famous catalog. Today we know that it was the remnant of a supernova that could be seen from Earth in the year 1054. The object is also known as the Crab Nebula.
Well known and very impressive is M 42, the Great Orion Nebula, a gas nebula and star-forming region. Another large gas nebula is the Rosette Nebula in the Unicorn. It is stimulated to glow by an open star cluster. Charles Messier missed this nebula, so it does not have an M number.
If you are more interested in galaxies, M 31 in Andromeda is still in a good observing position. But there are also some galaxies in the area of the Great Bear.