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    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.

Events for March 2014: Planet Sandwich Seasoned with a Sprinkling of Zodiacal Dust

Two realities - The image above gives you an idea of the true size and look of the planets visible in March skies. (From left, Venus, Earth, Mars, Jupiter, Saturn) That's one reality. What you see with your naked eye looks like stars - though very bright ones.

Two realities – The image above gives you an idea of the true size and look of the planets visible in March skies. (From left, Venus, Earth, Mars, Jupiter, Saturn) That’s one reality. What you see with your naked eye is much different.  Planets look like stars – though very bright ones  and some with distinctive hues.

At dusk Jupiter dominates the night sky high overhead –  think of it as one slice of bread for our sandwich. During morning twilight Venus dominates the sky low in the east – that’s the other slice. Between we have Mars on the evening side of midnight and Saturn on the morning side of midnight.

The “seasoning” – Zodiacal Light  – is interplanetary dust that forms a soft cone of light rising out of the west about 80 minutes after sunset – but is only visible if your skies are dark enough.

In total this makes a tasty show at any time of night to supplement the annual,  ever-advancing march of the stars. Here’s where and when to look.

The Zodiacal Light is the most challenging and can’t compete with the Moon’s light, so it’s available for the first two nights of the month, then comes into view again starting on the 18th and going for the rest of March, 2014.  To see it you need a clear sky to the west with no light pollution in that direction. You also need to allow your eyes to dark adapt. for 20 minutes. What you’re looking for is something roughly akin to the Milky Way in brightness, but in a soft pyramid shape that starts out wide as it rises from the horizon and leans to the south as it reaches one-third or more up the sky in the general direction of Jupiter. It’s really quite an amazing feature.

If you see it, reflect on this explanation from Wikipedia:

The material producing the zodiacal light is located in a lens-shaped volume of space centered on the Sun and extending well out beyond the orbit of Earth. This material is known as the interplanetary dust cloud. Since most of the material is located near the plane of the Solar System, the zodiacal light is seen along the ecliptic. The amount of material needed to produce the observed zodiacal light is amazingly small. If it were in the form of 1 mm particles, each with the same albedo (reflecting power) as Earth’s Moon, each particle would be 8 km from its neighbors.

For the metrically-challenged (that includes me) that means one dust particle every five miles! In the light of that information, it’s absolutely awesome if you see any thing at all!

Jupiter dominates the stars of Gemini, including the two bright twins to the left, Castor and Pollux.  In the midst of the brightest stars in our skies - the Winter Hexagon - it is the brightest of them all.

Highly recommended that you click this image for larger version. Hard to see the stars otherwise.

Jupiter  is on top these March nights, sharing the same general area of sky as the Gemini Twins. I took the picture (above) of it in late February – it’s position in March won’t change much, though it will get a little dimmer, it will still be much brighter than any star. As always, it’s fun to see if you can hold your binoculars steady enough to detect one of its four largest Moons. When it’s high like this you’re looking through less air and they may be easier to spot – but then, it’s a  bit hard on the neck to look so high in the sky while holding binoculars.

Again. to see any of Jupiter’s Moons your eyes have to be dark adapted, its best to use the largest, most powerful binoculars you can hold, such as 10X50, and you need an idea what to expect. The moons will be roughly in line with Jupiter’s equator – but at any given moment the number visible will vary, as will their distance from the planet, and which side they may be on. (They can all be on one side, they can be split two to a side, etc.) Jupiter together with its Moon – even when they are most distant, are only going to take up about 1/20th of the typical binocular field.

Here’s the sort of thing you are hoping to see:

How Jupiter’s moon might appear at one specific moment – in this case a moment when they were all on the same side of the planet. Of course the next night the view could be quite different. The letters stand for Europa, Io, Ganymede, and Callisto.

If this is your first time looking for the moons, do yourself a favor. Go to this page at the Sky and Telescope Web site and open the JavaScipt utility. It will tell you right where the moons are – and which is which – for any given moment.

As Jupiter dims a bit during the month, Mars becomes quite bright reaching magnitude -1.3 by the end of the month, and shines with a distinctive reddish hue. That’s  almost as bright as Sirius, but is no challenge to Jupiter, both of which appear white.

Click image for larger version. (Prepared from Starry Nights Pro screen shot.)

Click image for larger version. (Prepared from Starry Nights Pro screen shot.)

It rises about 3.5 hours after Sunset at the start of the month, but comes up during evening twilight at the end of the month. Generally it will be well placed for naked eye observing about an hour after it rises – those with small telescopes may want to wait another hour or two for a better view. That’s why I see it primarily as a late evening object.

You’ll find it by looking to the east about four hours after sunset as March begins. The Big Dipper will be high in the northeast. Follow the curve of it’s handle down to the bright star Arcturus. Continue this curve and you will come to Mars, roughly five degrees from the bright blue star, Spica. (Remember: When low on the horizon bright stars and planets will appear to sparkle and change color because you are looking through so much air.) While these relationships will remain the same, as the month goes on Mars will be rising earlier and earlier.

Click image for larger version. (Prepared from Starry Nights Pro screen shot.)

Click image for larger version. (Prepared from Starry Nights Pro screen shot.)

Saturn still is best seen in the early morning hours, though it rises just before midnight in the southeast. I think the best guide to it is the triangle it forms with Arcturus and Mars. Of the three corners of this triangle, Saturn is dimmest, shining with a soft yellowish light. However, it still outshines the stars in its vicinity.

You can’t miss Venus if you’re up an hour before sunrise. It actually comes up a couple hours before sunrise and in morning twilight is well above the southeast horizon an hour before sunrise. At about magnitude -4.7 (it gets a bit dimmer towards the end of March) it simply outshines everything except the Sun and Moon, so there’s no mistaking it and no difficulty finding it. Just look in the right general direction at the right time.

On March 27, 2014 a very thin, waning crescent Moon should fit in the same binocular field with Venus roughly three degrees up and to the left.

February 2014 Events: Obvious Jupiter, Morning Venus, Subtle Zodiacal and a timely wink from the Demon

Yep, you can’t miss Jupiter this month.  It’s well up in the eastern sky as it gets dark and brighter, by far, than even Sirius, the brightest star we folks in the north see.

What other special events are on parade this month? Well, the Moon provides a wonderful viewing – or photo op -with Venus in the predawn sky late in the month; the last two weeks of February will be a good time to look for that elusive Zodiacal Light about 80 minutes after Sunset, and if the weather on February 17 cooperates, we have a perfectly timed eclipse of Algol, the Demon Star, for folks in the Eastern Half of the US. ( There are other dates with the Demon available too for other parts of the world.)

So let’s start with Jupiter. You really can’t miss it even if you’re a beginner. In fact, if you’re a beginner this is a good time to let Jupiter be your guide to the Winter Hexagon. As mentioned in our “look east” post, you’ll find it in Gemini. Look to the southeast a couple of hours after sunset and here’s what you should see.

Click image for much larger version. To get the full beauty of this section of sky find an area with a clear horizon to the southeast and go out on a February evening a couple of hours after sunset. The chart shows what you'll see. The link below provides a small black-on-white version you can print and take into the field. (Prepared from a Stellarium screen shot.)

Click image for much larger version. To get the full beauty of this section of sky find an area with a clear horizon to the southeast and go out on a February evening a couple of hours after sunset. The chart shows what you’ll see. The link below provides a small black-on-white version you can print and take into the field. (Prepared from a Stellarium screen shot.)

Click here for a printable map of the above chart.

Jupiter reaches its highest point as it crosses to the south about 5 hours after sunset near the start of the month and closer to three hours after sunset at the end of the month. As the chart shows, Sirius will be lower and more to the south.

Moon and Venus team up for a Picture Perfect  Pre-dawn Sight

Venus is a morning star and really stays pretty close to the Sun this month, but as Sky and Telescope points out, there’s a great meeting of Venus and a thin crescent Moon on the morning of February 26. Here’s what to look for then.

Click picture for larger version.

Circle shows the typical view through ordinary binoculars – you may just be able to fit them both in the same field of view. Click picture for larger version.

Soft, elusive, and fascinating – Zodiacal Light

Mornings not your thing? Well from February 16 to March 2 the Moon will stay out of your way if you go out about 80 minutes after sunset and look for the elusive, zodiacal light. This is faint – sort of like the Milky Way – but its a pyramid of light rising up from where the Sun sets and going roughly halfway up the sky and leaning to the south.  To see it you must have dark skies pretty much free of light pollution. (A city to your west, for example, would likely ruin it.) And, of course, your eyes must be dark adapted.

Still, it’s a fascinating cloud of fine dust. Here’s what I said about it a couple of years ago – and it still applies:

You don’t need a totally clear horizon to see the zodiacal light, or binoculars, but you do need total darkness and that means little-to-no light pollution and no Moon. So you want to wait until a few days after full Moon to begin this quest. I feel I have a good shot at it from my favorite ocean-front observing point where I have a clear horizon to the west with no cities to create light domes there. Evenings in February and March – and mornings in September and October – are the best time for folks at mid-northern latitudes to look for this.

The zodiacal light is roughly the same intensity as the Milky Way, so if you can see the Milky Way from your chosen location, then you should be able to pick up this faint glow. Like the Milky Way, it stretches over a good deal of sky. It is widest near the horizon and gets narrower as it rises towards the zenith. You want to look for this starting  roughly 80 minutes after sunset. You can check for an exact time for your location by getting information from here on when astronomical twilight ends. (The drop-down menu on that page specifies the times for astronomical twilight.) As astronomical twilight ends you want to start looking. As with any faint object, your eyes need to be dark adapted, so I am assuming you have been out for at least 15 minutes with no white light to dazzle you. If you try to look for this earlier, you may confuse it with twilight. Much later and it is not as bright, for what we are seeing is sunlight reflecting off interplanetary dust particles – dust particles that orbit in the same plane as the planets – the area we call the zodiac – and thus the name for this phenomena, zodiacal light.

If you see it, reflect on this explanation from Wikipedia:

The material producing the zodiacal light is located in a lens-shaped volume of space centered on the Sun and extending well out beyond the orbit of Earth. This material is known as the interplanetary dust cloud. Since most of the material is located near the plane of the Solar System, the zodiacal light is seen along the ecliptic. The amount of material needed to produce the observed zodiacal light is amazingly small. If it were in the form of 1 mm particles, each with the same albedo (reflecting power) as Earth’s Moon, each particle would be 8 km from its neighbors.

For the metrically challenged (that includes me), that means one dust particle every five miles! And that causes all that light?! Awesome!

Now, about that Demon!

I wrote about Algol the “Demon Star” in this  posting for October, but it’ s still well placed for viewing in February, and if you look at the right time, you’ll catch it in mid-eclipse, which is cool. For those on the East Coast, the most convenient time will be roughly 7:45 pm. Technically, the eclipse goes on for about two hours with the lowest point – the star at its dimmest – at 8:44 pm EST.  But to appreciate this you should check it an hour before to see the normal brightness, then look again at 8:44 pm. Of course, you could start at 8:44 pm and note how it brightens during the next hours. Either way, it will convey why ancient star gazers considered this the “Demon Star.” These events happen often enough for them to notice it dimming every once in a while – sort of winking at them – and no other bright star does that, so it’s easy to imagine the stories that would be told.

Every 2.3 days Algol dims like clockwork, but it is only at its dimmest for about two hours, so to see it in this condition you really need to be watching at the right two hours. Fortunately, there are several places that will give you a list of times when this occurs – but many of these times will be while normal people are sleeping – and many more will be during daylight hours. However, each month there should be one or two dates when it is really a good time for you to catch Algol doing its thing.

Most of the listings I know of for Algol “minima” give date and time in Universal Time. What I like about the one at Sky and Telescope magazine, is it will calculate a list of coming Algol minima for you – and give you the Universal Time, plus your local time. So it’s easy to glance over it and see when it will be most convenient – weather permitting – for you to take a look. In my case, February 2014 gives me a couple of opportunities worth noting:

  • 02/14/2014 @ 11:55 pm
  • 02/17/2014 @ 08:44 pm

With winter weather it’s easy to get clouded out, so the more opportunities the better your chance of seeing something. I find these eclipses amazingly elusive and rarely see one, maybe because I think there’s always going to be another opportunity – and there will, but . . .

Update- March 5 – Outlook brightens for PanSTARRS!Events – March 2013: Get set for a real nice – BINOCULAR – Comet and more

NASA guide to PanSTARRS position and tail direction on different dates this month. This is NOT a prediction of tail length or comet brightness. It is likely tobe much shrter and fainter - but comets are full of surprises and so this still has the potential to be really nice.

NASA guide to PanSTARRS position and tail direction on different dates this month. This is NOT a prediction of tail length or comet brightness. It is likely to be much shorter and fainter – but comets are full of surprises and so this still has the potential to be really nice. (Click image for larger version.)

The latest indicators are that Comet PanSTARRS will put on a better show than anticipated just a week ago – as noted, comets are just not that predictable! – here’s a recent news item:

Observers in the Southern Hemisphere have been watching Comet PanSTARRS for weeks, but the Northern Hemisphere is due to get its first looks at one of the year’s most eagerly anticipated sky extravaganzas this week. And there’s good news for northerners: The up-and-down expectations for the cometary show are trending upward again.

March Observing Highlights  –

Comet PANSTARRS and its distant kin, the Zodiacal Light

First, let me stress Comet PanSTARRS is not likely to be nearly as bright as originally predicted – but it still should be a nice comet, especially when viewed with binoculars.  And remember – we have another due in November/December that should be much better. However, with comets we can only make educated guesses – they can – and have – surprised the experts over the years, sometimes under performing, sometimes over performing.

I’m linking this comet with the Zodiacal Light because both might be seen at their best on March 12 after sunset in the west. What’s more,  they are  both essentially dust reflecting sunlight,  presenting a related observing challenge, though they are radically different in size. March 12 may be the earliest time for a good look at Comet PanSTARRS in the early twilight – and it will be the last night in early March for the  Zodiacal Light which can be seen about 80 minutes after sunset for the first 12 days of March – after that the Moon will tend to wash out the Zodiacal Light until the last couple days of the month.

Quick Observing Guide:

  • to observe both comet and Zodiacal Light  at their best, hope for clear skies on March 12 – and some special comet luck 
  • to observe the Zodiacal Light  alone go out any evening during the first 12 days of March 2013 and look for it about 80 minutes after sunset.
  • to observe Comet PanSTARRS it may be visible – especially from low northern latitudes such as the southern US, as early as March 7 or 8th, but the week beginning March 12 will probably give the best opportunity for observers in mid-northern latitudes.

A comet is a “dirty snowball” that “melts” when it gets near the sun, giving off what can be a spectacular trail (tail) of tiny dust particles that reflect sunlight. When we think of a comet we are usually thinking of seeing one with such a tail.  And the Zodiacal Light? It’s tons of inter-planetary dust, much of it having accumulated over the years from many comets that eventually disintegrated as they made several trips around the Sun. And while your best views of Comet PanSTARRS will be when it’s near the Sun – but getting dark – your best view of the Zodiacal Light will be just as full darkness is arriving – about 80 minutes after local sunset.

The Zodiacal Light will be in a fixed position night after night – a huge, but very faint, light cone reaching from the western horizon and slanting up in the general direction of the Pleiades star cluster in Taurus  – Comet PanSTARRS will change position slightly each night, drawing away from the Sun. The Zodiacal Light is most certainly a naked eye phenomenon requiring a good view to the west and  skies that are largely free of light pollution in that direction.

The same basic requirements fit Comet PanSTARRS – you need a good view to the west with an unobstructed horizon, at least for the early – and probably best – views. While it may be visible to the naked eye, the best guess is this will be bets seen in binoculars. So by all means, break out the binoculars! You don’t need any thing special – ordinary, low-power ones will do, though if you have large astronomical binoculars, all the better.  And while you will be searching for the comet in the early twilight, do be careful. Wait until about 15 minutes after sunset before scanning the western horizon for it. At all cost, avoid looking with your binoculars at the sun, as that will seriously damage your eyes.

Yes, you are likely to hear that PANSTARRS is visible to the naked eye. Don’t get too excited, though, it’s visibility is a lot like that regular March visitor, the  Zodiacal Light – the numbers in reality don’t really add up. Thus the binoculars are highly recommended – even if its brighter than expected.

Great video guide to the comet from NASA

I read in Sky and Telescope this month that the Zodiacal Light is actually the second brightest “thing” in the Solar system.  Wow! Never prove that from my experience. I  have always found it elusive. I count myself lucky if I can see it at all!  But, of course, Sky and Telescope is right.  Here again there’s an important lesson relating to both the Zodiacal Light and a comet – the brightness they’re talking about is for a point object, but in our view of it, this light is spread out.

So when you hear the Zodiacal Light is beaten only by the Sun in brightness, you have to understand that this is determined by pretending all the light reflected from it was concentrated in a single spot – and it isn’t. It is spread out over a huge area of sky – widest near the horizon and getting narrower as it rises towards the Pleiades. For me it looks much like the Milky Way, only a bit fainter.

The same thing is true of a comet – but to a much lesser degree. That is, Comet PanSTARRS is fairly likely to reach magnitude 2 and if it does, well that’s as bright as the North Star, or most of the stars in the Big Dipper. But – and here’s the catch – that light will be spread out with much of it concentrated in the fuzzy head, but  some also appearing in the tail.

What’s more, as the comet draws away from the Sun it will almost certainly get fainter – and therein lies the crucial problem of seeing a comet at its best. What we are dealing with is a constantly changing set of variables. Generally speaking, the closer a comet is to the Sun, the brighter it is.  However, the closer it is to the Sun, the more it is competing with the lingering sun light. As the twilight deepens, the comet should stand out more – BUT, as the twilight deepens the comet is also getting lower in the sky and that means you’re looking at it through more atmosphere and that makes it appear dimmer.

So the joy – and frustration – of comet hunting is that how the comet looks to you will depend on your local weather, of course, but also exactly when you see it – how bright it is, how high it is, and how dark the sky is around it. That’s what makes viewing – and photographing – comets both fun and challenging.

So what’s the best bet for Comet PanSTARRS – for those in mid-northern latitude somewhere between March 7 and 20 probably about halfway in between. I plan to watch the weather closely from March 10th to 17th and take advantage of any clear evening to look for it. The farther south you are, the sooner it should appear at its best for you – the farther north,  the later in the month it will be at its best.

But remember – on a  clear night early in the month that you go comet hunting – hang around even if the comet is too low to see well – the Zodiacal Light should be best about 80 minutes after sunset when there is no – or little – interference from the Moon. (That means from March 1 to about March 12, 3013.)  If you see the Zodiacal Light – how well you see it depends largely on timing, local weather conditions, and the lack of light pollution.  In other words, it is not quite to finicky as the comet, but still a challenge.

Jupiter – King of the Winter Hexagon!

Wow! What a view to the south!

As the sky darkens on these March evening, don't hesitate to look due south for a wonderful view of Jupiter dominating the Winter Hexagon - thata rea of sky with more birght stars in it than any other! Click the image for a larger version. (Prepared from Starry Nights Pro screen shot.)

As the sky darkens on these March evening, don’t hesitate to look due south for a wonderful view of Jupiter dominating the Winter Hexagon – that area of sky with more bright stars in it than any other! Click the image for a larger version suitable for printing. (Prepared from Starry Nights Pro screen shot.)

The Winter Hexagon is one of my favorite asterisms encompassing a very rich area of sky contains eight very bright stars and that most recognizable of constellations, Orion.  But bright as these stars are, Jupiter will dominate them, outshining even Sirius, the brightest star for norther hemisphere observers. Take a look in that direction about an hour after sunset – in fact, you can’t hope but notice this brilliant area as you scan in the darkening even sky for the Zodiacal Light which shine faintly in a widening cone reaching from near the Pleiades to the western horizon.

And what a fabulous binocular sight!

Use your binoculars to:

  • Look for the fuzzy area in Orion’s sword  which hangs below his belt – the Great Orion Nebulae.
  • Look for the Hyades – the fabulous star cluster that makes up the “V” of Taurus and is just 150 light years away.
  • Look for the Pleiades – my favorite binocular target, a cluster of brilliant gem stone roughly 400 light years away.
  • And, of course, if you can hold them steady enough – brace against a pole, or the corner of a house – try to pick up one or more of the four bright moons of Jupiter.
The "V" of Taurus marks the Hyades cluster and the Pleiades are bit to the right as seen when looking south about 90 minutes after sunset this month.  Watch carefully over the course of the month and you will see Jupiter slowly change position moving towards Aldebaran, the bright star that marks the bull's eye. (Click for larger version. Prepared from Starry Nights Pro screen shot.)

The “V” of Taurus marks the Hyades cluster and the Pleiades are a bit to the right as seen when looking south about 90 minutes after sunset this month. Watch carefully over the course of the month and you will see Jupiter slowly change position moving towards Aldebaran, the bright star that marks the bull’s eye. (Click for larger version. Prepared from Starry Nights Pro screen shot.)

Oh – and I should add that Jupiter will have a real close call with a “young” crescent Moon on March 17, 2013. Exactly how close will depend on where you are, but for me on the East Coast of the US, the Moon will pass within two degrees of the bright planet and add to the fun of binocular observing on that night. They both will fit easily into the same binocular field of view!

Saturn now dominates the morning sky

Think of it as “coming attractions” if you’re not a morning person. Saturn crosses over into our late evening sky and by next month it will be quite easy t see at a reasonable hour.  For March 2013, however, it is primarily the dominant planet in the morning sky.

In fact, this is a rare month for planets – well, I should say planets are rare this month. Jupiter and Saturn are, for all practical purposes, the whole show – the other major planets being too near the Sun for easy viewing.

Our chart shows Saturn at  mid-month and midnight due southeast and about 23 degrees above the horizon. Spica – which is about half a magnitude dimmer than Saturn, will be about 18 degrees away. Be sure to look for the color difference. Saturn should appear creamy – maybe a tad yellow, while Spica is an icy blue.

Saturn and Spica at midnight in March 2013. (Prepared from Starry Nights Pro screen shot. Click image for larger version.)

Saturn and Spica at midnight in March 2013. (Prepared from Starry Nights Pro screen shot. Click image for larger version.)

More September 2011 Events: Say Goodby Saturn, Good Evening Jupiter, Good Morning Mars and Hello Zodiacal Light!

Hey, it’s a great Solar System month! Say goodby Saturn, good evening Jupiter, good morning Mars and hello Zodiacal Light!

We’ll get to the details in a moment, but essentially  Saturn rides off into the sunset, Jupiter is well place in the late evening, Mars is scampering across the morning sky at full tilt, and the end of the month will mark a great time to look for the almost phantom like , but lovely and mind-blowing in its details, Zodiacal Light. (Oh – and as bonus a very, very old Moon.)

Goodby Saturn

Yes, you can get a glimpse of Saturn, especially during the first half of the month – after that you would need to use binoculars. It’s really the single most beautiful object in a small telescope, but when it’s this low inthe sky the telescopic view is ruined by looking through too much air – so just take a look and wave goodby. But don’t weep. It will be well up  in the morning sky in a few months! Meanwhile, you can find it real easy on September 1 because there’s a 4-day old moon nearby. For the next week or two, look to the west about 45 minutes after sunset.

As soon after sunset as you can pick out the Big Dipper’s handle in the northwest, follow the arc of the handle to brilliant Arcturus and then continue on down to Spica – Saturn will be just a bit north of it. Here’s a chart.

This will help you find Saturn the first couple weeks of September. Click to get a larger version. (Prepared from Starry Nights Pro screenshot.)

Good evening Jupiter!

This is not a bad trade -Jupiter for Saturn – especially for those viewing with the naked eye, or binoculars. First off, Jupiter is absolutely dazzling – brighter than any other star or planet except Venus – and, of course, the Sun. This month it is even a tad brighter than normal as we draw a bit closer to it. It’s at magnitude 2.75.

To find it, just look for a bright star rising nearly due east about three hours after sunset the first of the month – around an hour after sunset by the end of the month. (Yes, stuff generally rises 4 minutes earlier each night and that time adds up quickly.)  What’s due east? Glad you asked because this is the month to find out – just look where the Sun rises on or near  September 23, 2011. The Fall Equinox is at 5:05 am EDT on that date which means the Sun will be rising due east – a good time to make some mental notes about objects on your horizon that help you recall exactly where east is for you.

Jupiter is fun because as Galileo discovered, even the smallest telescope reveals its four brightest moons and they constantly change position from night to night. They’re even visible in binoculars, but for this you need good eyesight and you have to find a way to hold the binoculars really steady.

Good morning Mars!

Jupiter’s no speed demon. It takes it more nearly 12 years to make a circuit of the skies. But Mars is and if you watch it in the early morning hours during September you’ll see it whipping past some pretty interesting heavenly sights and near the end of the month approaching one of my favorite binocular clusters, M44 – the Beehive!.   Here’s a chart to guide your search as Mars passes from Gemini to Cancer  on it’s way to Leo.

Mars path, week-by-week in September 2011. Chart is looking east roughly two hours before sunrise. Click for larger version. Prepared from Starry Nights Pro screenshot.

A binocular view of Mars as it approaches the Beehive at the end of September, 2011. Click image for larger view. Prepared from Starry Nights Pro screenshot.

Mars is actually between Castor and Pollux in brightness – but look for it’s reddish tint and compare it with Betelgeuse for color.

Basking in the Zodiacal Light 

The last week of September 2011 will be a good time to start looking for that most elusive of Solar System sights, the Zodiacal Light. This is another morning project that fits right in with observing Mars two hours before sunrise.  You actually have a brief window when it’s visible starting about two hours before sunrise and going to about  80 minutes before sunrise. After that the twilight will drown it out.

Looking for the Zodiacal Light  is much different than looking for a bright planet. You don’t need a totally clear horizon to see the zodiacal light, or binoculars, but you do need total darkness and that means little-to-no light pollution and no  – or very little – Moon. In Septmeber 2011 the last week will be ideal. I feel I have a good shot at it from my favorite ocean-front observing point where I have a clear horizon to the east with no cities to create light domes there. Mornings in September and October –  or evenings in February and March – are the best times for folks at mid-northern latitudes to look for this.

The zodiacal light is roughly the same intensity as the Milky Way, so if you can see the Milky Way from your chosen location, then you should be able to pick up this faint glow. Like the Milky Way, it stretches over a good deal of sky. It is widest near the horizon and gets narrower as it rises towards the zenith. You want to look for this starting 120 minutes before sunrise, but I advise you also allow at least 15 minuyes to half an hour for your eyes to dark adapt. (For projects like this I frequently keep a red flashlight near my bed and use it to preserve my night vision when I get up.)  If you try to look for this later, you may confuse it with twilight. What we are seeing is sunlight reflecting off interplanetary dust particles – dust particles that orbit in the same plane as the planets – the area we call the zodiac – and thus the name for this phenomena, Zodiacal Light.

If you see it, reflect on this explanation from Wikipedia:

The material producing the zodiacal light is located in a lens-shaped volume of space centered on the Sun and extending well out beyond the orbit of Earth. This material is known as the interplanetary dust cloud. Since most of the material is located near the plane of the Solar System, the zodiacal light is seen along the ecliptic. The amount of material needed to produce the observed zodiacal light is amazingly small. If it were in the form of 1 mm particles, each with the same albedo (reflecting power) as Earth’s Moon, each particle would be 8 km from its neighbors.

For the metrically-challenged (that includes me) that means one dust particle every five miles! And that causes all that light?! Awesome!

A morning bonus!

OK, you’ve seen Mars, you’ve seen the Zodiacal Light – now make it a triple – go for the slither of a moon – the oldest piece of moon you are ever likely to see – about 28 days 8 hours –  just south of east about half an hour before sunrise on September 26. This is for mid-northern latitudes and the Eastern Seaboard – it will get older and closer to the horizon and thus more difficult to see as you move west. You’ll need binoculars and you’ll want to look half an hour before sunrise and quit looking in another 15 minutes whether you find it or not. I say that because it scares me when folks look east with binoculars too near where the Sun is about to rise. You will do serious damage to your eyes if you look at the Sun with binoculars.

So here’s what you should see.

Can you spot the Moon in this simulation. It is likely to be even harder in real life, so use binoculars, but be careful. Stop looking as sunrise approaches. (Prepared from Starry Nights Pro screen shot.)

Events: March 2010 – Venus takes center stage, west and a marathon night

The date I’m circling on my calendar for this March is the 16th – that’s when I want to go to my favorite spot that has a clear western horizon and catch the sun setting practically due west, Venus emerging in the early twilight, and with luck, the thinnest of crescent moons next to it. Then I’ll wait another hour and see if I can detect the ghostly glow of the zodiacal light, and for the rest of the night – with telescope handy – I have my choice of the entire catalog of Messier objects, something that can only happen in mid-March!

Of course, the only thing magical about March 16 for me is the combination of Venus and the crescent moon. Truth is, this combination will be available in an easier to detect form the next night as well – and Venus is available in the western sky all month! But on March 1, half an hour after sunset, it is just 4 degrees above the western horizon. By March 15 it is nearly twice as high, half an hour after sunset, making it much easier to see. By the end of the month it is more than 11 degrees above the horizon at that time, and if you can find it in your binoculars, you’ll see another bright “star” right below it in the same binocular field – that will be fleeting Mercury. Mercury first puts in an appearance about the 20th of the month, but doesn’t really become easy to see until the last days of March.

This chart is good for mid-northern latitudes. The exact position of Venus and the Moon will change depending on your location on Earth. Do not look until after sunset and be especially careful when using binoculars to wait until the Sun is well below the horizon. Click image for larger view. (Chart prepared from Starry Nights screen shot.)

If you want to see both Venus and the crescent moon on March 16, first notice exactly where the Sun sets. Wait 10 minutes, then start scanning that area of the horizon for a bright “star.” Venus will be easier to find than the crescent moon, though on the next day the moon will be higher and easier to find. If you find Venus, the Moon will be to the right (northward) and lower. It may just barely fit in the same binocular field, but most likely you’ll have to let Venus slip out at the upper left and be looking for the moon to come into view in the lower right.

The zodiacal light is available any time of year, but is much easier to detect in the evening sky about 80 minutes after sunset in February, March, and April – with March being the best. For more details about what it is and how to observe it, see this posting.

As to seeing every one of the objects in the Messier catalog, you should first understand that only a few of these are visible to the naked eye, the most famous being M45, the Pleiades. The Astronomical League classifies 42 of the 110 Messier objects as “easy” to find with ordinary binoculars – assuming you know just where to look. For the rest you really need a small telescope, or large astronomical binoculars. During most months at least some of them are obscured because the Sun is in the same section of sky as they are. They can also be drowned out by the light of the moon. But in mid-March, each year, nearly all Messier objects are far enough away from the Sun to be seen, although two of the 110 (M74 and M30) are still so close to the Sun that they are very difficult targets.

Since the mid-1980’s this idea of prime time for Messier objects has led to an extraordinary “sport” of sorts where amateur astronomers pick a night in mid-March, and stay up all night with the avowed goal of finding each of the 110 Messier objects. They call it a Messier Marathon. Frankly, I have never tried it and the idea doesn’t have much appeal to me because when I find one of these fascinating objects I like to stay with for at least half an hour. So the most I would see in a 12-hour night is a measly 24! Still, I like the idea of staying up all night and looking at different Messier objects as our spinning Earth brings each into view.

This year the key date for the Messier Marathon is March 13. That’s a Saturday night, and there will be no interference from the Moon. So if this is your thing, hope for good weather. As with all astronomical events, even when they happen every year, it is still rare when the weather and your personal schedule cooperate so you can enjoy them fully. Of course, if work is no issue you don’t have to be strict about the date. Any time within a week either way gives you a good shot at finding nearly all of the Messier objects in a single night.

Oh – and don’t forget the equinox on March 20th.

I love the equinoxes for their long nights, moderate weather, and sense of cosmic balance. This is the time when the Sun is half way in its journey north – or in September, in its journey south – and is rising and setting very close to due east or west. This year the vernal equinox occurs on the afternoon of March 20th in my Eastern Time Zone and that means sunset on that day is pretty much due west. OK, technically it’s a bit off target, but astronomers are used to “close enough being good enough.” Even Polaris, the “pole star,” is nearly a degree off the north celestial pole, but most of the time we treat it as if it’s right on. If you’re new to observing the night sky, this is a great time of year to get your bearings at your favorite observing location. Watch either the sun rise or the sun set and note the landmarks near it – that way you’ll have a quick way to identify the eastern or western point on your horizon. (You could use a GPS instead, but I’m an incurable romantic and would rather use the motion of Earth and Sun. )

Look East! March 2010 roars in like a Lion – with Saturn tagging behind!

March roars into our eastern night sky like a lion – Leo, the Lion that is, led by the Little King “Regulus” and in 2010 brings Saturn with it. Just ahead of it is a special binocular treat, M44, a veritable beehive of stars barely visible to the unaided eye. Think of it as the lion’s whiskers. And don’t forget to look for the zodiacal light!

Leo does look much like the Lion depicted inthe 1603 Bayer catalog.  Click image for larger version.

The stars of Leo do indeed trace out some key parts of the Lion depicted in this plate from the 1603 Bayer atlas. (Click image for larger view.) Note that the bright star that marks the tail is named "Denobola," which in Arabic really does mean "tail." We encounter this also in the tail of Cygnus the Swan where the bright star is named "Deneb." The Arabic star names are frequently descriptive. (Image courtesy of Linda Hall library of Science, Engineering and Technology.)

 

I don’t usually put an emphasis on constellations, but in March it is fitting, for it makes it easy to remember what it is you see in the East just after sunset and besides, this is one of those constellations where when you connect the dots it looks something like it is supposed to look.

In fact, in my mind’s eye I can see the classic lion of the old Bayer star charts, but I more often see two very easy to remember asterisms – the Sickle that forms Leo’s head and mane, and the Triangle that forms Leo’s rump. And Regulus, our new bright guidepost star for this month, means “little king,” or “prince,” in Latin. That fits right in with the lion‘s reputation as King of the Beasts. And what a lovely image to have a prince leading a lion onto the night-time stage this month! Here’s our eastern sky chart. (As usual, click the image for a larger version, or download a printable version.)

Click image for larger view. Use link below to download a printer-friendly version. (Chart developed from Starry Nights screen shot.)

Click here to download a black-on-white (printer-friendly) version of this chart.

If you look in the same spot an hour or so later – or wait until mid-month, you will get the special treat of seeing Saturn, a favorite target for small telescopes, though this month it will be a tad disappointing to telescope users. Right now Saturn’s rings appear tilted as seen from Earth so that they make a thin line extending out from either side of the planet. In most years, they are at such an angle that they make a much better display. But Saturn is a special feature for this year, 2010. It won’t be back with the stars of Leo for another decade. So lets get on to the prime star in the east that’s there every year at this time, Regulus.

Is Regulus memorable in its own right? Well yes. It’s a star that is spinning so fast that if we could see its disc, it would look like a beach ball that someone sat on. It takes Regulus about 16 hours to make one rotation – in comparison our Sun, a smaller star, takes about a month to rotate. In fact, if Regulus were spinning just a bit faster, it would spin itself apart!

The rapid spinning gives Regulus an equatorial diameter that is about one-third bigger than its polar diameter. This also results in the polar regions of Regulus being much hotter than its equator.

Regulus is also a multiple star system, but as such rather dull visually. The second star in the system is much fainter, so it can barely be detected by a skilled observer using binoculars – and in a telescope it’s so far away from the primary star that they don’t seem like a pair at all. Both the primary and secondary are spectroscopic doubles – meaning the companions are so close we can’t see them with a telescope.

Though a relatively young star – about 250 million years as compared to the five billion year age of our Sun – Regulus is apparently nearing the end of its normal life as a “main sequence” star. That is, it’s about to finish burning hydrogen, which means it will soon go into the last stages of its life. But according to Jim Kaler, Regulus is also a curious case. It appears to have a very close white dwarf companion which scientists believe once was much larger and brighter than Regulus. But the gases were drawn from the white dwarf into Regulus making it both huge and bright and causing it to spin the way it does.

In total, Regulus is another example of how what looks like a common star to us, is quite fascinating when seen in the light of modern science.

Vital stats for Regulus:

• Brilliance: Magnitude 1.35, 22nd among the brightest stars in our sky; shines with the luminosity of about 150 Suns.
• Distance: 77 light years
• Spectral Type: B7V
• Position: 10h:08m:22s, +11°:58′:02

The buzz about the Beehive (M44), Mars, and Leo’s whiskers

In ancient times the constellation Leo extended much farther east and west, and M44 was considered to be its whiskers.

from “The Next Step – Finding and Viewing Messier Object” by Ken Graun

Whiskers indeed! I like that. It’s a great way to remember where to look for M44, for if you can find the Sickle – the huge head and main of Leo – then all you have to think is “now where would his whiskers be?” Scan 2-3 binocular fields in that direction – westward – and you should soon stumble upon M44, the Beehive. In 2010 this is especially easy. Start at Regulus and scan towards Mars, one of the brightest objects in the sky. M44 will be along this path, much nearer to Mars than to Regulus. Here is a chart you can use to find it – and to map the changing position of Mars, which will be especially interesting in March.

Following Mars and finding M44, the Beehive - or if you like, Leo's whiskers! Click chart to see larger image. (Chart developed from Starry Nights screen shot.)

Click here to download a black-on-white (printer-friendly) version of this chart that you can also use to chart the movements of Mars.

Over the next couple of months Mars will serve as a bright beacon making it easier to locate M44 whose other names are “the Beehive,” and Praesepe, which is Latin for manger. And if you have dark skies, away from light pollution, you will see this as a small, wispy cloud, perhaps suggestive of Leo’s whiskers. It is, in fact, a beautiful star cluster as binoculars or a small telescope will reveal. Galileo first discovered its true nature and in this hazy patch discovered more than 40 stars. You should see about that many with your binoculars. This is one of the nearest star clusters to us, and although there is still debate over its exact distance, it is around 580 light years. That compares with about 400 light years for the Pleiades. The two clusters are pretty close to the same size, but M44 is considered much older. M45 – the Pleiades – is estimated to be 78 million years old, while M44 is thought to be about 660 million years old. As star ages go, they’re both quite young.

The Latin name, Praesepe, is worth examining because it explains the names of two relatively bright stars which flank it – Asellus Borealis and Asellus Australis. Borealis means “northern” and Australis means “southern.” Asellus means “ass” – as in donkey – and Praesepe means “crib” or “manger.” In other words, the Beehive apparently looked to some like a pile of hay in a manger and these two flanking stars were donkeys, eating that hay, one to the north and one to the south. In binoculars the scene should look something like this screen shot from Starry Nights software to which I’ve added labels.

M44 and surroundings as it would appear in binoculars with a 5-degree field of view. Click image for larger view. (Chart derived from Starry Nights software screen shot.)

Click here to download a printer-friendly version of this chart.

The two donkeys are about as bright as the stars in the handle of the Little Dipper, so under dark skies should be faintly visible to the naked eye with the northern one the dimmest. The third star, Eta Cancri, is dimmer still. Its name, however, indicates that it, the Beehive, and other stars shown here are all part of the rather obscure constellation known as Cancer, the crab.

There’s a revealing naked eye exercise buried here as well. This is a good month to chart the course of Mars across the background of stars. Mars starts out the month appearing to run away from the Beehive – that is, it’s moving westward against the background of stars. Then, just before mid-month it appears to stand still for a couple of days as it reverses direction and starts to come back towards the Beehive (eastward) as if tugged by an invisible cord. In April it will skip right by, missing the Beehive by less than a degree and passing between the Northern Ass and the Southern Ass.

Keep in mind that all this happens over a period of days and weeks, and to see it you need to carefully chart the position of Mars against the background of stars on several nights. This sort of exercise helps you appreciate great observers who charted the heavens before the invention of the telescope. It also helps you understand how puzzled early observers were by the apparent behavior of Mars and why this had them scratching their heads for centuries trying to make sense of these movements in a universe where Earth was at the center of everything. During any given night, of course, everything appears to move westward because of the rotation of the Earth. The movement we’re interested in here is the revolution of Earth and Mars around the Sun.

It’s much easier today – with a sun-centered solar system – to understand why Mars first appears to move in one direction, then the other. This is caused simply by Earth overtaking Mars as the two planets orbit the Sun at different distances and speeds. Here’s where the planets are in mid-March, courtesy of John Walker’s “Solar System Live” online orrery.

Click image for larger view.

See the Zodiacal Light

Finally, don’t forget to look for the zodiacal light this month – especially if you missed it last month.

You don’t need a totally clear horizon to see the zodiacal light, or binoculars, but you do need total darkness and that means little-to-no light pollution. I feel I have a good shot at it from my favorite ocean-front observing point where I have a clear horizon to the west with no cities to create light domes there. Moonless evenings in February, March, and April – and mornings in September and October – are the best time for folks at mid-northern latitudes to look for this subtle phenomena. In March 2010 that means to look about 80 minutes after sunset on a clear night between March 1 and March 15.

For more detailed information on this, see the February posting here.

Events-February 2010 – Happy Valentines Day Jupiter – we’re onto you!

Ah, to be romantic in mid-winter!  And this year, on February 14th, we have Jupiter  – king of the gods – being joined by Venus – goddess of love, beauty, and fertility –  beside the soft glow of a slim crescent moon! Is that appropriate, or what? (OK, we’ll ignore the fact that Jupiter is married to Juno.)  The question is, will we be able to see this little tryst? Or will it be so close to the horizon – and the Sun – that it will remain a figment of our imaginations. One thing I’m sure  of – it will be a challenge. Other challenges this month for naked eye and binoculars include:

Jupiter, Venus, and the Moon

Sky and Telescope describes this encounter this way: “Venus and Jupiter appear 2 degrees apart on February 14th, when an ultraslim young Moon joins them in a tight formation.”  Yep! “ultraslim” is right. When I asked Starry Nights Pro to show me this scene I couldn’t even see the moon it was so slim! That’s because I’m on the East Coast. West Coast observers will see a moon that’s a bit older – and thus larger – so they will have a better shot; but I’ll try. Here’s the screen shot from Starry Nights for 15 minutes after sunset at my latitude, about 42 degrees north.

Click image for larger view. Printer-friendly version linked below.

Click here to download a black-on-white (printer-friendly) version of this chart.

If you want to see this live, you first need an unobstructed western horizon. Then, a lot of luck in terms of no clouds. If you meet those two requirements, then a good pair of binoculars, or a small telescope would be handy. Be careful though – make sure the Sun has fully set before you start looking. I plan to wait 5 minutes, then I’ll start scanning the horizon. I expect to pick up Venus first.  Jupiter will be a bit higher, but also dimmer, so it should pop out second and be in the same binocular field of view as Venus. I expect the moon will be last to put in an appearance, but if I put Venus to the left side of my binocular field, I should be able to pick up the Moon on the other side.

Normally, of course, Venus and Jupiter are easy targets – downright dazzling. But now we’re talking about finding them in bright twilight and very near the horizon. Thirty minutes after sunset Venus will be barely one degree above the horizon – that’s about the width of your pinky held at arm’s length – without gloves!  And Jupiter will be about three degrees above the horizon. Venus sets just 38 minutes after the Sun and Jupiter about 50 minutes. See why it’s going to be hard to surprise these celestial lovers?

But if you get clouded out, don’t despair – they actually get closer during the next couple of days, though the moon will quickly rise much higher and so not be an intimate part of the picture. Now if it’s clear enough to see these three – or even two of them, then I’m going to wait another 50 minutes to see if I can detect the elusive zodiacal light.

See the Zodiacal Light

Now this is something much different. You don’t need a totally clear horizon to see the zodiacal light, or binoculars, but you do need total darkness and that means little-to-no light pollution. I feel I have a good shot at it from my favorite ocean-front observing point where I have a clear horizon to the west with no cities to create light domes there. Evenings in February and March – and mornings in September and October – are the best time for folks at mid-northern latitudes to look for this.

The zodiacal light is roughly the same intensity as the Milky Way, so if you can see the Milky Way from your chosen location, then you should be able to pick up this faint glow.  Like the Milky Way, it stretches over a good deal of sky. It is widest near the horizon and gets narrower as it rises towards the zenith.  You want to look for this roughly 80 minutes after sunset. You can check for an exact time for your location by getting information from here on when astronomical twilight ends. (The drop-down menu on that page specifies the times for astronomical twilight.)  As astronomical twilight ends you want to start looking. As with any faint object, your eyes need to be dark adapted, so I am assuming you have been out for at least 15 minutes with no white light to dazzle you. If you try to look for this earlier, you may confuse it with twilight. Much later and it is not as bright, for what we are seeing is sunlight reflecting off  interplanetary dust particles – dust particles that orbit in the same plane as the planets – the area we call the zodiac – and thus the name for this phenomena, zodiacal light.

If you see it,  reflect on this explanation from Wikipedia:

The material producing the zodiacal light is located in a lens-shaped volume of space centered on the sun and extending well out beyond the orbit of Earth. This material is known as the interplanetary dust cloud. Since most of the material is located near the plane of the solar system, the zodiacal light is seen along the ecliptic. The amount of material needed to produce the observed zodiacal light is amazingly small. If it were in the form of 1 mm particles, each with the same albedo (reflecting power) as Earth’s moon, each particle would be 8 km from its neighbors.

For the metric-challenged (that includes me) that means one dust particle every five miles! And that causes all that light?! Awesome!

Watch the bright Asteroid Vesta dance through Leo

This spring you get a chance to follow one of the brightest asteroids as it dances about the constellation Leo. This will be particularly easy to find with binoculars on the night  of February 16 (February 17 UT) , or the night before or after that one.  The fast-moving asteroid will be close then to the second brightest star in the easy-to-spot asterism of Leo’s Sickle. To find this, look east about three hours after sunset. Here’s what you should see with the naked eye.

Click image for larger version of this chart. Chart was developed form Starry Nights screen shot.

Click here to download a black-on-white (printer-friendly) version of this chart.

Once you are sure you have found Gamma Leo, then look at it in your binoculars.  You should see something like what is shown in the circle, though your binoculars may show a somewhat larger field. What is neat here is that Vesta is moving right between Gamma and 40 Leonis and it will take it about three nights to complete the journey.  You can start looking for Vesta earlier, however, if you want. It will enter the field of view shown at the lower left about February 7. And it will leave the circled region, exiting to the upper right, on about February 25. It would be fun to spot it on several nights and use the printer-friendly chart, linked below, to mark your own observations of its movement.

Click image for larger view. Printer-friendly link below. (From Starry Nights screen shot.)

Click here to download a black-on-white (printer-friendly) version of this chart.

Catch the Demon in Demise

I wrote about Algol the “Demon Star” in the posting for October, but it’ s still well placed for viewing in February, and if you look at the right time, you’ll catch it in mid-eclipse, which is cool.

Every 2.3 days Algol dims like clockwork, but it is only at its dimmest for about two hours, so to see it in this condition you really need to be watching at the right two hours. Fortunately, there are several places that will give you a list of times when this occurs – but many of them will be while normal people are sleeping – and many more will be during daylight hours. However, each month there should be one or two dates when it is really a good time for you to catch Algol doing its thing.

Most of the listings I know of for Algol “minima” give date and time in Universal Time. What I like about the one at Sky and Telescope magazine, is it will calculate a list of coming Algol minima for you – and give you the Universal Time, plus your local time. So it’s easy to glance over it and see when it will be most convenient – weather permitting – for you to take a look. In my case, February 2010 gives me a couple of opportunities worth noting:

  • 02/07/2010 @ 09:45 pm
  • 02/10/2010 @ 06:35 pm

You can learn much more about the minima of Algol – and get specific predictions for any date with translations to your local time  by visiting this page at Sky and Telescope.

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