Caoimhín's Content

Today we are taking a look ahead at the month of January. Starting nice and early in the month, we begin on just the 3rd of January. Just after sunset, the Moon will be right next to Jupiter. At just 5:30 the Moon and Jupiter are already up, right next to each other, right in Gemini.

If we take a closer look, we’ll see that this is our January Full Moon. In Ireland we’re seeing it at 99.7% and as we go later in the night it goes down. The Moon will be 99.8% just as it rises is, the fullest that we’re going to see the Moon in Ireland for this full Moon. As it rises, the Moon draws level with Pollux and Jupiter, making it a great example of the Moon’s motion over the course of just one night. If you take a look at the Moon just after sunset, it forms a triangle with Jupiter and Pollux low in the East. As we move later, we’ll see the Moon drawing level, forming a straight line with the two bright objects. It then passes out the other side, forming another triangle with the Moon on the opposite side, by the time we come up to sunrise. The two bright “landmarks” make it easy to see just how much the Moon moves even in one night. If we take a closer look, it is a Full Moon, but we can see a little bit of shadow there around the side, as it is about 0.3 percent off of a 100% Full Moon. The Moon is also nice and close to us, just 360,000 kilometers away out of a potential 350,000 minimum distance. The Moon is still a supermoon, very much like the supermoon that we saw the previous month in December. However, if we follow the Moon all the way back around to last month, it’s just at 353,000km away. The supermoon that we’re getting in January, is a little bit less super than the Full Moon that we already had in December, but it is still a supermoon, and it is very close to Jupiter here in the sky as well.

Speaking of Jupiter, we’re going to move forward to the 10th. On the 10th of January, Jupiter is illuminated 100%, which is an indication that Jupiter is at its opposition. With Jupiter directly behind the Earth relative to the Sun, if we get Jupiter as close as possible to directly above the south it should be just a bit after midnight. In Ireland, we’ll say 12:30, just after midnight, puts Jupiter right above the south, the highest point that it’s going to reach in the sky. Taking a closer look, getting the opposition of Jupiter close to winter is good because the highest position that it’s going to reach in the sky is actually higher than the highest position it would reach in the sky if this was a summer’s night and it was at opposition. This is thanks to our tilt, the same reason the Sun is lower during the day in wintertime, objects at night are higher in the night sky at winter time. This night in particular gives us a fantastic view of Jupiter, with all four of the Galilean moons arranged around the sides of the largest planet, separated by quite a good distance making them easy to see. This is going to be one of the best nights to take a closer look at Jupiter, not just because it’s at opposition, but because of the arrangement of its moons. We can come back a little bit earlier in the night and still see Jupiter quite well, because Jupiter is at opposition, so it’s going to be up all night long from sunset to sunrise.

Looking at it at 9:15, Jupiters already nice and high in the sky and the Great Red Spot is just coming into view. In fact, we’ll go back a little bit more, even closer to sunset at just almost 8 o’clock and the great Red Spot isn’t yet visible. Moving through the night again the Great Red Spot comes around into view. It’s fully pointing at us by just about 10 o’clock, so within just a couple of hours. As we continue through the night, coming up to midnight, when Jupiter will be at its highest in the sky, the Great Red Spot is going to slide out of view. Just before it does, just before we reach midnight, the Great Red Spot slides out of view and its completely out of view by the time we’re through to just after midnight. This makes for a great example of how quickly Jupiter turns around, it is a very, very fast rotating planet.

Not only does Jupiter rotate very quickly, its moons move very quickly. You would, of course, need quite a good telescope to be able to see Jupiter’s Great Red Spot, but the moons are a lot easier to see. Coming back to almost 7 o’clock in the evening, and we can see only three of Jupiter’s moons. It doesn’t take long for the fourth to come into view. They move around each other over the course of the night, another great example of the Jovian system moving around very quickly, whether it’s the rotation of the planet or the positions of those Galilean moons around it. The opposition of Jupiter is one of the big things that’s coming up. Without even needing a telescope, you can see Jupiter change position around these dates. If we zoom out just a little bit and go through a few days, we can see Jupiter moving ahead and then coming back. This is Jupiter’s retrograde motion. We have prograde motion coming through December to January, with Jupiter appearing to move East to West, just like the stars but a little faster. Then Jupiter turns around, it does a sort of a loop as we essentially catch up to it and move past it. Once we have it at its opposition, and then move past the opposition, we get further away from Jupiter, because we’re orbiting the Sun on a shorter orbit, which is a little bit quicker.

Continuing to push a little bit later into the month, we’re going to come around to morning time just so that I can keep an eye on the Moon. We are going to get a New Moon in January as well, so let’s move forward until the Moon’s illuminated percentage is at the lowest that we’re going to see it, which is just 0.4% illuminated, definitely a New Moon. This is going to be the darkest night of January, it’s going to be the night where the Moon isn’t interfering at all. Now that we’re almost a month from the shortest day of the year, around the 18th, we’re getting our sunset closer to 5 o’clock. The sky is still bright as we get to 5 with our first bright objects coming through there. The sky will be getting dark just as we come up to almost 6 o’clock and our dark night will be just a little bit shorter than the dark nights that we were getting in December because we are past the solstice. However, it’s not going to really be that noticeable until we get through to February, when the difference will be a little bit easier to notice because. We’re gaining just a few minutes of day a day, so it takes a while to add up to be a noticeable difference in the amount of sunlight that we’re getting.

There aren’t too many meteor showers that are particularly good in January. There is the antihelion point as always, very near Jupiter, which is another good example that it’s at opposition. The antihelion point is directly behind us relative to the Sun, more or less, and Jupiter is directly behind us relative to the Sun when it’s at opposition. They both pretty much line up in January. They are a little bit apart on the 10th, but not by too much. Turning around to the north, we’ve got the Gamma Ursae Minorids. These are different to the Ursids, which didn’t label themselves as Ursa Minorids despite occuring in the same constellation. These are the Gamma Ursa Minorids, a very minor meteor shower, we can see it there peaking on the 18th with about 1 meteor an hour. Thankfully, the Quadrantids are a better meteor shower peaking earlier in the month.

For the peak of the Quadrantids we’re going to have to go back to the start of the month, back to the night of the Full Moon, which is going to interfere with our view. This shower can get up to 200 meteors per hour, but usually closer to 30 or so. They are coming up to their peak just the night of the 3rd. As they come up to their very highest rate they are pretty low in the sky. They’re really peaking at just about 9:30 on the 3rd of January, with the Full Moon interfering with them and their radiant has just come above the horizon, which means that we’re going to see even less. If we very quickly pop out to the countryside to give ourselves the best view possible, we’re getting maybe 11 to 38 being seen here in Ireland thanks to how low they are in the sky, probably even less thanks to the light of the Moon. In this case, the maximum of 38 in Ireland would coincide to a perfect view of 200 or so, which itself isn’t very likely. As we move through the night, the potential amount of meteors starts to drop down, whereas the amount of meteors that we can see actually climbs. This is because the radiant is getting higher into the sky. For us here in Ireland, our potential view of the meteor shower is going to peak closer to 3 o’clock in the morning on the 4th, when the actual zenith hourly rate is only 19 to 65, but we’re getting up to 44. Variable meteor showers only have peaks in certain years. Whether or not we’re going to get 200 or closer to 20, varies a lot from year to year. They’re not as reliable as, for example, the Geminids.

That is the Quadrantids, the main meteor shower that’s coming up next month. Jupiter is coming to opposition and we have that wonderful Full Moon, a lot of these things are happening quite early in the month. We have those to look forward to in January and I very much hope you get to see them. I also hope that you enjoyed this piece, if you did, please do like it. If you like this kind of content, then make sure to subscribe to this website and my YouTube channel. Thank you very much for watching and hopefully I’ll see you back here next time.