Jupiter, March, Sky What to see in the night sky: March 2021
Mercury. Now mercury is in a poor position in the morning sky all month, long because the ecliptic, the plane of the solar system effectively has a really shallow angle with the eastern horizon at this time of year in the morning sky. Yes, now mercury is well it’s. Also, quite close to jupiter and saturn, so there’s a triple whammy there that jupiter and saturn are also going to be very poorly placed as well um. Yes, no it’s a mercurial. It can often be low down and poorly placed uh, but uh on the fifth of march uh. It is uh lies 19.5 minutes from uh jupiter. As you say, uh there is quite a notable difference in brightness. Mercury will be magnitude. 0.2 jupiter will be much brighter magnitude, minus 1.8 and, as you said, saturn slightly fainter, 0.9 magnitude, it’s just 8.8 degrees to the west. So a nice nice uh combination of planets there, but they will all be very low down and quite difficult to see this at this time of the meter, yeah and um we’re not going to do much better with venus. Unfortunately, because that reaches superior conjunction when it lines up in the sun on the far side of its orbit on the 26th of march, but that does mark a transition from it being a morning planet to an evening. Planet. So there’s a little bit of hope in there. There is, but it’s not it’s, not going to be as good an apparition as it was uh during 2020.
Is it. I know that that so, as you say, um the the after the 26th of march of venus will appear in the evening. Skies uh, but it’s it’s not going to be a as good an elongation as we had uh previously with venus really high in the sky. But nonetheless it will be a nice observable target and it’ll be nice to watch the phase decrease and see what phenomena we get uh on the into the things like the uh. The cloud changes and the cusp caps be interesting to follow all that again, and it will be nice to have it back, but not quite as good as previously yeah. Okay. Well, as far as the uk is concerned, the planets are all of the planets. Unfortunately, are rather poor at the moment and mars. Um is probably the only one which isn’t hampered by its proximity to the sun in the sky. However, despite it being the most northerly planet at present, which is quite an accolade, the appearance of mars continues to deteriorate because it’s unable to reach its highest position in the sky in darkness and at the beginning of march mars, shines at mag plus 0.9 and presents A diminishing disc, which is 6.4 arc seconds across when you look at it through the eyepiece of a telescope, um a bit disappointing that, to be honest, yes, uh by the end of the month. It gets worse, of course, because mars is moving away from us.
For now uh he will have dimmed to magnitude 1.3 and through a telescope it shrinks to just 5.3 arc seconds, so you will need at least a 12 inch, telescope or larger, i think, to see convincingly any service details. So i guess that really marks the end of the apparition it does for a telescope, but with the naked eye there are still some nice things to look out for at the beginning of march, it’s located south of the pleiades open cluster lying 2.7 degrees from the Cluster on the 4th of march now it sits 7 degrees, north of orange giant aldebaran on the evening of the 19th of march. The date when mars has its monthly visit from the moon, and on that occasion the moon will be visible between mars and aldebaran. Roughly one third of the way along the line, joining both objects starting from the planet and the mar the moon will appear as a 33 lit waxing crescent on that date. So a third illuminated um, so that actually that’s quite a nice scene. I remember popping out many years ago, and i saw that with the moon. I think it was venus at the time that mars will do and those two clusters together and took a very lovely photograph of that grouping. So if it’s, clear, it’s worth getting out and having a go at that yeah, as you say, these little pairings of various celestial objects which don’t require any optical aid at all, you can just go outside and look at them are quite nice to uh quite nice To to to take part in richard notes that this is really now the end of the mars apparition and mars will enter a slow period where it will be too small for serious observation for quite a long time, because the next opposition occurs on the 8th december 2022 miles be quite good, it will be high in the sky, it’d be for the uk skies it’ll be in taurus, if so, that’s quite high up for us uh, but about 60 degrees up isn’t it it is.
It is so very good altitude, but unfortunately only 17 arc seconds across so quite a bit smaller than the than what we had in 2020 uh, but nonetheless it will be nice to have it high in the sky. So we should look forward to that, because this is and that’s not going to happen for a little while marshall’s going to be gone for my skies for a for a little while now yeah, okay, well, uh, jupiter and saturn. We can sort of lump together because they’re quite close to one another in the sky. We’Ve already mentioned them um, but they are in the morning sky, rising approximately 45 minutes before the sun at the start of the month, but that low shallow ecliptic angle will keep them very low down. So they will be quite tricky to see over that period. Now. Heading further out in the solar system to the ice giants, uranus neptune they’re not particularly well placed either neptune – is in solar conjunction on the 10th of march, so it’s not visible and uranus has its observing window closing very rapidly. As the evening twilight comes up to meet it, so we’re gon na have to wait until later on in the year to catch up with those two planets. Yeah. Yes, it’s a bit of a shame, isn’t it but yes, but never mind so they’ll get better again. Eventually, it’s interesting, actually that you get these periods where everything moves out of the way, at the same time, so you’re bereft of um planets to look at really in the sky.
But i suppose the saving grace, if you like the solar system, is the fact that the um, the ecliptic, makes a very steep angle with the western horizon at this time of year, just after sunset. So if you have something like the crescent moon hanging there in the evening sky, that’s well worth looking out for, because it’ll be in a very good position, it’s a good time of year to observe the moon and or the early phases of the moon. I should say and to enjoy a view of it through a telescope. Yes, so we substitute our planets for the moon and that’s, not a bad swap because the moon has lots of detail that’s easily visible in telescopes, small telescopes and binoculars yeah, okay! Well, let’s. Look at some of the specials on offer. We’Ve already mentioned that mars is going to be very close to the pleiades open cluster um it’s, slowly, making its way across the sky south of the pleiades at the beginning of the month. Uh closest approach will occur on the evenings of the 3rd and 4th of march, so that’s something well worth looking out for and if you’ve got a camera, try and take a photograph of that meeting together. We get clear skies on the fourth we’ve got vesta, which reaches opposition they’ll, be shining away at magnitude plus 5.9, in the constellation of leo, which is pretty well placed, and in theory, if you’ve got a really dark sky, you should be able to see it with A naked eye, yeah it’s, quite difficult, though, unless you have got a very dark sky uh.
I should mention that even through a telescope you’re not likely to see very much, of course, uh, but it is worth looking for because it’s a nice thing to be able to to tick off the list to say you’ve observed it. Yes, okay! Well, on the 14th look low above the western horizon, and here you should be able to spot a very thin waxing lunar crescent, the moon’s setting approximately one hour after the sun and, as i mentioned earlier, the good angle, the ecliptic makes makes thin moons spotting at This time of year, quite um, quite favorable, so that’ll be worth well worth looking out for yes and on the 15th, the moon’s libration state and phase favors observing features close to the northeast and limb of the moon. So here you’ll find uh the mari humboltianum uh. Together with craters like uh, nansen, hain and boss, so it’s worth looking out for these craters because uh these features, because it’s only when you get a favorable vibration like this, that they’re easy to find and see. So i do quite like librational observations actually because they are quite challenging to make yeah absolutely and it’s also worth bearing in mind that on the 28th of march, the full moon occurs close to lunar perigee at this at this particular time, meaning that the moon will Appear slightly brighter and fractionally larger than an average full moon and, of course, um the usual ferrari will will arise around it being a super moon, yes, but um yeah, but in reality it’s not a huge amount of difference in its appearance, um to a regular full Moon, in fact, the um the way it works, the the full moons either side when you get the actual um closest full moon to perigee, which i think happens next month, it’s in april it’s about 12 hours away from perigee in april, but the moon’s either side Of that entire in month time um are very close to perigee as well.
So the difference between those full moons and the actual perigee full moon for the year is so minimal that you wouldn’t know somebody told you that’s right and it was it’s. For all intents and purposes, there is no observational difference at all, um, of course, on the 28th, we should remind everybody that the clocks go forward at 0, 1, 0, 0 ut by one hour uh to 2020 bst, and this marks the official start of british summer Time let’s hope somebody notifies the weather. Does it work on clock time, Laughter, okay, well, let’s, head out, then into the universe and look at the stars. During march, the center of the sun’s disc appears to cross the celestial equator, the projection of the earth’s equator into the stars and on this occasion as it crosses it, is heading from the south to the north and that marks what’s known as the northern hemisphere’s spring Or vernal equinox for those south of the equator, of course, it’s the southern hemisphere’s autumn equinox as the um as the sun is heading down for them. Now it’s often said that day and night are equal at the equinoxes, but that’s actually an approximation. There are other factors which affect the length of night and day slightly for different latitudes and the actual days, when day and night of equal length, if that’s important to you um occur a few days adrift of the equinox and they’re known as equiluxes. Oh you go.
You say: it’s uh, it’s, often fun to tell that to people who think uh. You know that that’s what equinox means, but no uh, if only astronomy, was that simple it’s never supposed to be anything. Is it no? No, never it’s that time of year, though, where we find that the you know the really dominant, bold brash constellations of of winter, like orion, they edge off to the west now and in their place uh the more subtle constellations of spring, i think, probably the most Recognizable springtime constellations early for me, uh is leo the lion and again it’s one of those constellations that does look like what it’s supposed to be. It kind of does look like a lion sitting in profile um, its brightest star is regulus uh and it represents uh. Essentially, a big cat, a lion um, but i don’t know i think, if you imagine it, you can see the lion shape or at least at the very least a domestic house cat sitting down. But really maybe you don’t see that no to me it’s more like a sphinx yeah it’s, that sort of thing, but it does look like what it’s supposed to look like and regulus its brightest star uh is actually fairly easy to to find yeah. Well, one way to find it is to locate the plow or saucepan, which is very recognizable it’s overhead late evening. It sort of comes up on the north east part of the sky and heads overhead.
But if you extend the pointers, those are the two stars furthest from the handle in the saucepan um. If you um point them up with respect to where the pan would be, if it was sitting on a surface, if that makes any sense, that’s more or less over towards the left or down when it’s directly overhead and that points at polaris. But if you extend them in the opposite direction, a little bit of artistic license, they can work as reverse pointers and um. They will point at regulus, yes and regular, say you could you could tell when you found it because it marks the punctuation dot of a sort of backward question mark asterism what we call the sickle of leo? It probably looks more like a question mark than a sickle, and that represents the head of the lion. Um. The rectangular body extends to the east of the sickle and eventually ending in a pointed triangle representing the lion’s tail um, the middle bright star. The end of the tail is denebola, which is beta leonis, and this is an interesting star because it has a rapid rotational rate. Its speed is 128 kilometers, a second, so that’s quite a high velocity, and it means the star probably bulges out at the equator yeah. I think it’s actually getting close to the point where it would break up at that speed. So um, it is a very fast rotator. The sun is, is pretty leisurely.
The sun goes around very, very slowly compared to most other stars, but of course, it’s also worth mentioning that vesta, which we mentioned just now, is opposition in leo it’s, actually towards the um, the rear of the creature, if you’re looking for it. So if you’ve got a good dark sky sight, it may be worth having a look inside the magazine where there’s a guide on um, giving you a challenge to try and locate vesta by picking out some of the stars which are getting closer and closer to its Brightness, it is quite a tall order, uh to ask you to see it with a naked eye, but it’s worth having a go there’s another thing to tick off. If you can can pick it out. Yes, okay well draw a line between regulus the brightest star in leo and caster, which is the northern twin star and locate the light. The midpoint of that line and if you’ve, got really good dark skies, it’s possible to see a misty patch there, which is, of course the beehive cluster messier, 44. that’s. Quite an impressive cluster isn’t it it is, and it does look like a little beehive. Although there’s. No chance of confusing it with a comet, so i don’t really know why it’s, why it’s on there added it to his commentary? Catalogue, yes, but it is a lovely, it is a lovely open cluster and it does kind of have a beehive shape so what’s, the name um.
It sits at the center. As you say, this inverted y shaped constellation, which is cancer. The crab, although none of the stars in the constellation of cancer, are particularly bright uh, but it is visible from towns and cities and i think it is fairly distinctive as a constellation. Do you think so? It’S yeah it’s accubenz is the bright well. I was gon na say, it’s the brightest. I don’t think it is the brightest star. I think beta can cry which is called altaf uh that’s, the brighter one of um or the brightest one in cancer, so it’s a bit of a mixed up constellation but it’s worth mentioning that just to the west of accuburns is another messier cluster m67 and i, Like that it’s very rich cluster it’s much dimmer than the beehive, but it is compact and very, very, very rich in stars. Yes, i i actually have never seen it really no i’d say i should. I should make more of an effort and take a look at it, but it’s like a lot of these objects. Open clusters i find are often best seen with uh small telescopes, so uh it would mean of setting up a second telescope going, have a look because uh, even in a medium sized telescope. A lot of these star clusters are sort of they fall outside the field of view. I think you’d be surprised with m67. I think you need to make the effort.
I shall maybe look at even with a bigger telescope, especially as it’s estimated to be of similar age to the solar system, and many of its stars have similar chemical properties to our own sun and for a while it was thought the sun might have actually been Born in m67 and been ejected into space, and but it’s now thought that’s unlikely, but it’s a nice. A nice thought nice cluster, nice cluster. To look for all right well immediately: south of cancer. We have a lovely sideways sort of teardrop pattern, which represents the head of hydra, the water snake um, the largest constellation by area in the entire sky. What a pity that there are no bright stars, the brightest star is um uh, which means the solitary one. In fact, if you’ve got that it’s interesting, that teardrop shape um sort of points to the east and then if you follow the line of that and imagine it as a curving neck down to alpha, which isn’t too far down to the south and slightly to the East of the teardrop, it looks a bit like that classic photograph of nessie. You know the surgeon’s photo. Oh yeah yeah. It looks like somebody’s arm coming out of the lake, which is probably what it was. No, it was a fake wasn’t it it wasn’t. Of course it was a fake. Yes, yes, of course, yeah it’s. It does look a little bit like that. Uh uh, it’s, it’s, it’s a it is a.
It is worth trying to look for it. If you can find it, you probably do need uh darker skies, though, to be able to see many of the stars in it. You do and it does carry a number of interesting constellations on its back, which will reveal themselves as the as the weeks pass um. But you’ve got sexton’s the sextant, which is very difficult to identify it’s. Just a couple of really faint stars. Crater the cup is faint, but it it is a decent pattern. It does look a bit like a cut sideways view of a cup, but the best one is corvus, the crow, which is a small but it’s, actually quite a bright constellation. Yes, um with a nice quadrilateral there, which is an asterism known as the sail, because it’s supposed to represent the sail of an ancient sailing boat, drifting along the horizon. Right again, you probably all need dark skies and uh low horizon a good imagination and a decent amount of imagination to see that well plenty to see in the march nights guys. So i wish everybody clear nights for it: uh thanks pete.