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  • Rapt in Awe

    My Journey through the Astronomical Year

    Think of this as a "companion text" to this, the main web site. Not required reading, butI hope you'll find it interesting and helpful.

Observing plans for April 2009

 

M105 and two companions, NGC3384  and NGC3389 three of the galaxies oyu may see this month - but don't expect them to look like this terrific picture take by Jim Misti. Live telescope view are in black and white and very dim - but startling still, because they are live - you are interacting directly with the photons fromthes egalaxies.

M105 and two companions, NGC 3384 and NGC 3389, three of the galaxies you may see this month - but don't expect them to look like this terrific image take by Jim Misti of Misti Mountain Observatory.. Live telescope views are in black and white and very dim - but startling still, simply because they are live - you are interacting directly with the photons from these incredibly distant and huge galaxies.

This is the month for galaxies, but only with binoculars and telescopes. For the unaided eye, though, it’s the month dominated by the Lion with a great line up of planets as well. Mercury puts in an excellent performances, Saturn dominates in the evening, and Jupiter and Venus put in brilliant appearances before dawn.

 

Here’s a summary of some prime April observing targets for unaided eye, binocular, and telescope. First, the unaided eye list. (All charts with this post are screen shots  – with some  modifications by me  – from Starry Nights Pro software. They are  made for my latitude, 41.5-degrees north – however they should serve as a reasonable guide for anyone within 10 degrees of latitude either direction. To find your latitude, go here.)

Unaided eye

Mercury is a primary target during the last half of the month because it’s generally so elusive, but this is an especially good appearance. See this post for description and chart.

Saturn

Saturn is easy if you are familiar with Leo - and even if you're not, it is one of the brightest "stars," high in the east as the twilight ends.

Saturn is easy if you are familiar with Leo - and even if you're not, it is one of the brightest "stars," high in the east as the twilight ends.

Venus and Jupiter 

Early riser? Check out Venus and Jupiter. Look  low in the east (Venus) and southeast (Jupiter) as per this chart. (With really steady binoculars or a small scope you can see one or more of Jupiter's four largest moons.)

Early riser? Check out Venus and Jupiter. Look low in the east (Venus) and southeast (Jupiter) as per this chart. (With really steady binoculars or a small scope you can see one or more of Jupiter's four largest moons.)

Arcturus – April signpost star

The signpost star for April – the one to be sure to learn if you are just starting out – is Arcturus. Just follow the arc of the Big  Dipper’s handle to find Arcturus. (Go here for detailed description and chart.)

Getting to know the Big Bear

Everyone knows the “Big Dipper” - but several cultures saw this asterism as a bear - with a curiously long tail -  part of the larger constellation known as Ursa Major - the Big Bear. April is a good time to try to see the bear as he claws his way up the sky in the northeast.

Everyone knows the “Big Dipper” - but several cultures saw this asterism as a bear - with a curiously long tail - part of the larger constellation known as Ursa Major - the Big Bear. April is a good time to try to see the bear as he claws his way up the sky in the northeast. (Click picture for larger image.)

Now THAT’S a Lion!

Ahhh . .. a constellation that looks as it should! Leo.

Ahhh . .. a constellation that looks as it should! Leo.

If you already know the bear, it’s time to meet the Lion – Leo.  Leo contains the signpost star for March, Regulus, as its brightest member. The whole Lion image works for me, but I’m also used to thinking of  Leo as two distinct asterisms that are easy to recognize and remember – the sickle and the triangle. If you put them together they make a pretty credible lion.  The  sickle marks the lion’s head and  mane,  the triangle is his  rear haunches. And that last star at the east end of the triangle – well, it’s name is Denebola and “Deneb” means “tail.” When it comes to constellations it doesn’t get much better than this – even “Regulus” makes some sense, for it’s Latin for “little king” or “prince.” (I get the feeling Leo would accept the “king” part, but take issue with the “little.” )

Other signposts 

There are a  lot more signposts stars  and easy asterisms available in the hours of late twilight and full darkness. Here’s a list of key stars and asterisms you can see in the April evenings – assuming you have already learned these in previous months: In the north: Polaris, the Pointers, the Guardians of the Pole, the Handle of the Dipper, Mizar.

Roughly, from east to west: Arcturus, Spica, Regulus, Castor and Pollux,  Procyon,  Betelgeuse, Orion’s Belt,  Rigel, Aldebaran.

Zodiac – ecliptic

The Zodiac in the evening sky in April  is marked, from east to west by: Virgo, Leo, Cancer, Gemini, and Taurus. (Learning these constellations – their order and some rough idea of what they look like – is a helpful key to learning the rest of the night sky. For one thing, this is where you will find the Sun, Moon, and planets.)

Advanced naked eye observer targets

M44, the Beehive, can be found on this chart between Leo and Gemni.This is much dimmer than the Pleiades and the Hyades, two clusters you may already know. In fact, it will be just a faint, hazy patch.

M44, the Beehive, can be found on this chart between Leo and Gemni.This is much dimmer than the Pleiades and the Hyades, two clusters you may already know. In fact, it will be just a faint, hazy patch. (Click chart for larger image.)

 

M44, the Beehive, can be found on this chart between Leo and Gemini.This is much dimmer than the Pleiades and the Hyades, two clusters you may already know. In fact, it will be just a faint, hazy patch.

M45, the Pleiades, is getting low in the northwest, but still visible, as is the slightly higher – and physically closer cluster – the Hyades.

M42 – the star birth region in the sword of Orion – looks like a fuzzy star to the naked eye.

Coma Berenice

Find Arcturus, find Denebola - connect those two with an imaginary line, then travel along it a bit more than half the way from Arcturus to Denebola. Go up a bit and you should see a fine sprinkling of stars, visible in dark skies with your naked eye, but certainly visible with binoculars. This is Coma Berenice.

Find Arcturus, find Denebola - connect those two with an imaginary line, then travel along it a bit more than half the way from Arcturus to Denebola. Go up a bit and you should see a fine sprinkling of stars, visible in dark skies with your naked eye, but certainly visible with binoculars. This is Coma Berenice.

Melotte 111 – better known as Coma Berenice – is  following close behind Leo in the east.

For binocular and  wide-field  small telescope users

The easy list for binocular users repeats many of the objects on the  unaided eye list.  A few of these are actually best seen in binoculars and small, wide-field telescopes, so they are not just for beginners.

The objects that really look great in binoculars, include from east to west – Coma Berenice (Mellotte 111), M44 – the Beehive, the Hyades, and , of course, M45 , the Pleiades.

The previous charts in the naked eye section takes care of Coma Berenice and the Beehive. If you want a farewell look at  Orion’s Belt (surrounded by an open star cluster that doesn’t get the attention it deserves), or the Hyades, and the Pleiades, don’t wait too long. They’re still visible in the west, but getting lower each night and by the end of the month are really too low for a good look. Our chart (below) shows them in the middle of the month when they’re still high enough – assuming you have a clear western horizon – to see well.  (If you make a special trip to a spot with a clear western horizon to catch Mercury in the western sky shortly after sunset, hang around for it to get darker  so you can say farewell to these winter friends. )

lookwest1

Look west at 9 pm in the middle of the month for a farewell tour of some wonderful winter star clusters - Orion's Belt, the Hyades, and the Pleiades. (Click for a large image.)

There are several other objects that can be found with binoculars. I don’t regard binoculars and small telescopes as the best way to see these objects, but I think looking at them this way is important for two reasons. First, finding these with low-powered, wide field instruments will increase your finding skills and your general knowledge of the sky. Second, we all need to look at these in low-powered, wide field instrumens from time to time to give us a sense of context – otherwise the telescope views of them become abstract and disconnected from reality – sort of like watching TV.

Binocular finds

 

Mizar - a double star and then some in the Big Dipper's handle.

Mizar - a double star and then some in the Big Dipper's handle.

The easiest to start with this month is Mizar, the famous double star in the handle of the Big Dipper. If you have good eyes and your skies are steady you can “split” Mizar and its wide companion, Alcor, with your naked eye. Certainly you can split it with any size binocular. Try your naked eye first. No luck. Try binoculars. Got it?  OK, now that you know what you’re looking for, try it with your naked eye again. In even a small telescope, Mizar itself splits nicely into a handsome pair of stars.

How about an engagement ring – sort of?

A broken engagement? I have difficulty completingi n my imagination the "engagement ring" that makes a diamont of Polaris. Still, it's a nice grouping of 7th and 8th magnitude stars and perhaps I', justb eing too literal.

A broken engagement? I have difficulty completing in my imagination the "engagement ring" that makes a diamond of Polaris. Still, it's a nice grouping of 7th and 8th magnitude stars and perhaps I'm, just being too literal. In any event, here's what you should see in binoculars or a small telescope. You can complete the ring with one of the two stars I've pointed to - but which one? For me, neither gives a really satisfying result. But this little asterism is a nice way to confirm, when using binoculars, that you indeed have Polaris in view.

Meanwhile, in a galaxy far away . . . 

Want to go galaxy hunting? It is, indeed, mind bending to see objects that are millions of light years away and contain billions of stars while using nothing more than a good pair of binoculars, or a very small telescope.

In ordinary binoculars these objects are all a challenge and require dark skies. They become easier if you can mount your binoculars – or use a small, wide-field telescope – and especially easier if you can boost your power to 20-30X.

 

To find M51, first find Alkaid, the bright star at the end of the Dipper's handle. Get that in sight and look for the 5th magnitude star 24 CVn. It forms a large triangle with two dimmer stars of about 6th magnitude. A small triangle of still dimmer, 7th magnitude stars, is my favorite guide. But you do need clear skies and good, steady binoculars -and then you will only "detect" it - not really observe it. (Click for larger image.)

To find M51, first find Alkaid, the bright star at the end of the Dipper's handle. Get that in sight and look for the 5th magnitude star 24 CVn. It forms a large triangle with two dimmer stars of about 6th magnitude. A small triangle of still dimmer, 7th magnitude stars, is my favorite guide. But you do need clear skies and good, steady binoculars -and then you will only "detect" it - not really observe it. (Click for larger image.)

Of my short list, I think the easiest target is M51, the Whirlpool galaxy, which is really two galaxies in collision. It’s easy because you can start with the bright star at the end of the familiar handle of the Dipper, Alkaid.  The chart tells you where to go from there. If you have the ability to adjust your power – and thus your field of view – start with low power and first find the two triangles of stars shown. Center the smaller triangle in your field, then increase your power and M51 should be visible – though it’s helpful to know what to expect (two very dim, small clouds almost blending together) and averted vision helps significantly. Don’t expect miracles – you’re dealing with light that’s been traveling for something like 15 million years – it’s bound to  be a little weary. 

M81, 82 – ear mites in the Great Bear

 

It's almost the same distance from corner to corner in the Big Dipper's cups as it from Dubhe to M81 - roughly 10 degrees. Drawing an arrow through these bright stars isn't precise, but it gets you in the neighborhood and you should look for 24 UMa, a star that just a tad too dim to be called 4th magnitude, but in clear, dark skies would be visible to the naked eye and certainly will show up well in the binocular field.

It's almost the same distance from corner to corner in the Big Dipper's cups as it from Dubhe to M81 - roughly 10 degrees. Drawing an arrow through these bright stars isn't precise, but it gets you in the neighborhood and you should look for 24 UMa, a star that just a tad too dim to be called 4th magnitude, but in clear, dark skies would be visible to the naked eye and certainly will show up well in the binocular field. Click for larger chart.

 

I love M81 and M82 because they are two very different galaxies that fit in the same field of view, but finding them is a challenege – no convenient bright stars nearby.  I use two reminders. One is “the Great Bear has ear mites.” Not sure who first said that, but these two huge, dynamic galaxies do seem like mites stuck behind the Bear’s ears – assuming you know the figure of the Bear.  If you don’t surely you do know the asterism of the Big Dipper and if you cut across the “cup” diagonally as the chart shows, you get yourself pointed in the right direction. Don’t epect to see these with low power. I can just make them out with my 12X36 image stabilized binoculars. Having larger, higher-powered binoculars mounted so they are steady is critical – or better yet, a small, wide field scope where once again you can increase to 20-40X. Once in the neighborhood, use this chart to zoom in a bit and see the relationship between the two galaxies. They won’t look like their pictures – but even at low power,  one should appear roundish and the other more cigar-shaped.

 

The smaller circles show a typical small telescope field at roughly 24X. Note the north-south between the two, as well as their relationship to the star UMa 24. Can you see a difference in brightness? in shape? (Click for larger chart.)

The smaller circles show a typical small telescope field at roughly 24X. Note the north-south alignment between the two, as well as their relationship to the star UMa 24. Can you see a difference in brightness? in shape? (Click for larger chart.)

 

 

These two are about half as far from us as M51. Well, that actually depends on what you take as their distances. See, galaxy distances are real approximations and there is serious disagreement among folks who know much more than i do. So one book I trust tells me M51 is 37 million light years away, another I trust says 15 million. And this pair – well, a good ball park figure is about 9 million.  There’s also disagreement about brightness, but of these three, M1 is the brightest, M82 the faintest – M51 falls inbetween. But that ,too, is debateable as we’ll see with out next pair – uh, trio of galaxies.

The pair that’s a famous “triplet”

What may be an easier pair – not really brighter, but easier to find this month – are M65 and M66 in Leo – the famous Leo Triplet. How can a triplet have just two galaxies? It doesn’t. But the third one is notoriously more difficult to see, though quite large

If you find these two, try to decide which is brighter. See, my “experts” disagree. One auhor I respect as a super observer has them one way. Most authorities – and another author I respect – sees them as just the opposite. I can’t make up my mind. I’ve recorded them both ways in two different years and now I know too much to trust my judgment. That is, I’m prejudiced by what I’ve read and what I think I’ve seen. You probably aren’t – so which is brighter – M65 or M66 – and which is which? For that you need to pay attention to the charts and which way is east.

You have an extra aid in finding these two this year because Saturn’s in the vicinity. But even without Saturn, it’s simple – just locate the triangle that represents the haunches of Leo the Lion.

 

Draw a line between the star marked "Chertan, Chort" at one corner of the Leo Triangle and the 4th magnitude star Iota Leonis - both should fit in your binocular field of view.  You'll find the Triplet on that line, halfway between. But they are faint and it takes dark skies and steady binoculars to see them. A small scope is better. (Click to enlarge.)

Draw a line between the star marked "Chertan, Chort" at one corner of the Leo Triangle and the 4th magnitude star Iota Leonis - both should fit in your binocular field of view. You'll find the Triplet on that line, halfway between. But they are faint and it takes dark skies and steady binoculars to see them. A small scope is better. (Click to enlarge.)

Please note the directions on our chart. In the sky, northis always towards the North Star, Polaris. But when you are facing the earthly direction of south – as you will be when looking at Leo – east is to your left. East/west is  important here because M65/M66 line up pretty much east/west with M66 the eastern most of the two. NGC3628 is to the north. You won’t see it in binoculars. You may in a small telescope. It is fairly bright – but it’s large and it’s light is spread out, making it ghostly.  It’s also an edge-on spiral, which doesn’t make it any easier to see – long and thin in a generally east/west direction.  Here’s a closer view of these three.

 

My guide for finding these in a small,low-powered telescope is the "J" asterism to the right. The brightest star in its magnitude five, the others seven and eight. Once I've located that I'm sure I have the right field for the fainter galaxies.  Note that the ghostly member of the three is to the north. (Click to enlarge chart. )

My guide for finding these in a small, low-powered telescope is the "J" asterism to the west. The brightest star in it is magnitude five, the others seven and eight. Once I've located that I'm sure I have the right field for the fainter galaxies. Note that the ghostly member of the three is to the north. (Click to enlarge chart. )

There’s another nearby trio of galaxies in Leo that this time includes four! Hey, if a pair can be a triplet, then a trio can be a quartet -w ell,a ctually, a quintet, but that fifth one is really elusive.  But we really re toeing the line between telescope and binocular targets here and I count these give much more on the telescope side of the line. 

Objects for amateur telescopes

We’ve already looked at many of these objects with the naked eye or binoculars. You can use the charts above  to find these same objects for telescopic viewing. 

This group need a wide field, low-power eyepiece in your scope to appreciate – M45, the Pleiades, M44 the Beehive, and the Hyades.  Orion’s belt really needs and especially wide field – 2 degrees or more – and Coma Berenice is a better binocular target –  few scopes can get that low and wide to show it to advantage. Of this group, the best telescope targets are M45, the Pleiades – though they getting awfully low – and M44 the Beehive, which is very well placed, high in the sky, for study.

The Beehive is also known as “the manger” and I wonder if it should be called a “Christmas Tree.”  Looking at it with a low-powered, 50mm scope recently – the Sparrow Hawk – I certainly saw it that way. See this recent blog post for  more on the Beehive as a Christmas tree – with charts.  Wonder if anyone else see it this way? Depends, I think, on how large a scope you use.  There are also some interesting multiple stars in this cluster, though I haven’t finished the write-up of my recent observing of them. Stay tuned. The one write-up I did find on the subject was misleading. 

The art and craft of Galaxy observing

Step 1 – Lower your expectations. Galaxies are not ogoing to look like their pictures. Here the camera does much better than the human eye, gathering much more light and revealing all sort of faint detail. 

Step 2 – Raise your expectations. No kidding. It’s a mental game, I know, but darn it, you are actually, physically interacting with stars whose energy was released in your direction millions of years ago.  I know this sounds a bit mystical, but having your brain pinged by these photons need to be appreciated for what it is – awesome!

Step 3 – Dark adapt, dark adapt, dark adapt – and protect your dark adaption. Don’t even use a red light unless you have to, and then close or cover your observing eye. 

Step 4 – Take your time. Sit down. Study. relax, Study. Use averted vision, of course – move your eye and let the galaxy move. Jiggle the scope -gently tap its side. To see and record the kind of detail an excellent observer records takes hours. So don’t think a quick peek is going to do it for you.

Step 5 – Experience counts – sorry – but it does, My old and weakening eyes see more than many a much younger newcomer with much better vision simply because I’ve been there before. I know what to expect. So be patient. It will come to you and if your eyes are younger and better you will soon see much more than I do. 

Finally, don’t lose sight of your goals. You need dark skies, of course – but don’t write off galaxy hunting only because you don’t have the darkest skies possible.  You can still see them. But having more telescope helps. Stephen James O’Meara did his observing for his excellent books with a 4-inch refractor – but he was halfway up a mountain under extremely dark skies in Hawaii. However, what he saw an awful lot of people on the light polluted East Coast of America should be able to see – with a typical 8 or 10-inch reflector.

One other thing you’ll learn when hunting galaxies is the meaning of the word “transparency.” It seems amply clear – no pun intended. But honestly, I would not blame the beginner – or even intermediate observer – who thought one clear night was much like another. They are not. there are nights of exceptional transparency and with experience you’ll come to recognize them. 

In any event, go with what you have. Don’t try to set a world record – just enjoy what you can see. For me the ultimate goal remains – be rapt in awe – and for that I can deal with something far, far below ideal conditions, equipment, skills, and experience.

Galaxy targets

Our galaxy targets for the month are essentially the same as those listed under binocular observing and the same charts apply. we will, however, go after one more group in Leo.

These galaxies are all visible in the most modest amateur telescopes under good dark skies – anything from 50mm on up. But I would advise the beginner to start by using the largest telescope you can.  I feel my skill in observing galaxies was fed by switching back and forth between my 15-inch reflector and much more modest instruments, including refractors of 102, 80, 66 and 50mm. But first comes the largest instrument simply because it gathers more light and size still counts – the larger the aperture the more you’ll see. Period. but I’ve spend loads of time with the pristine, high contrast images of a good small refractor and feel that has taught me as well. There’s no single, perfect solution.

Also, contrary to what some people think, galaxies can benefit from at least a reasonable amount of magnification. With binoculars you generally detect the presence of a galaxy. With a small telescope you can start to observe it. You can evaluate its shape and details and make a rough judgment call on its classification – elliptical, spiral, irregular. But don’t expect details to jump out at you. It takes sharp focus, concentration, and time. Trying to draw what you see also helps significantly – even if you’re the world’s worst artist. 

So go  after M51, M81, M82, M65, M66, NGC3628 – see what you can learn to see. Then for a different experience turn your gaze to another triplet in Leo – M95, M96, M105 – and its companions.

The triplet that’s a quint

 

The key is to find Rho leonis, a star that's on the bright side of 4th magnitude and fairly isolated. USe it to draw inoyur mind a flashlight beam that is bounded by two of the triangle stars that make up Leo's haunches and these galaxies fit nicely in that imaginary beam. Click to enlarge.

The key is to find Rho leonis, a star that's on the bright side of 4th magnitude and fairly isolated. USe it to draw inoyur mind a flashlight beam that is bounded by two of the triangle stars that make up Leo's haunches and these galaxies fit nicely in that imaginary beam. Click to enlarge.

 

I find M95 and M96 a relatively easy pair, though about twice as far apart as nearby M65 and M66, so you need a low power field of at least two degrees to capture  this pair of galaxies and their companions.   If you can get   a wide enough field on a large enough telescope that should include M105 which always strikes me as a double galaxy. It has a quite bright companion right next to it that, while mentioned in most text, does not  seem to get the attention it deserves. It is NGC 3384. There’s a second companion, but this one is inconspicuous – NGC3389.  It is 12th magnitude and only going to show up in larger scopes under good conditions. But stop and think a moment – we are talking about being able to see four entire galaxies, each with billions of stars, in the single field of view of a small telescope – and maybe see a fifth galaxy as well! That’s awesome by my definition!

So we’ve progressed from seeing a single galaxy in collision with a second (M51); to seeing two distinctly different, large galaxies, M81 and M82; to seeing three galaxies in the same field of view M65,M66, and M105 with a fourth thrown into the mix – NGC3384_ and maybe a fifth – NGC3389!

Does it get any better than this? Well – yes.  If the sheer acumulation of galaxies is your goal, wait unti we tiptoe through the Virgo Cluster – but that’s at its prime for May.  For now, we’ll be satisfied by seeing part – and it  is just part – of what the Bear and Lion have to offer. 



 

 

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