November 2010 Events – Meteors, Moons, and more

Late-breaking news – could Comet Hartley 2 produce a meteor shower to open November? See this NASA news release.

There’s no single, mind-boggling astronomical event for November, but it’s a nice month to keep an eye out for a number of things – and some are especially interesting if you like getting up early.

But first, let’s not forget the king of planets and the Demon Star!

Jupiter et al, plus Algol

Jupiter is in its prime – and dominating our prime-time observing – nice and high, nice and big, and with dancing moons that you can even see in binoculars if you can only find a way to hold them steady enough. Fortunately, there are several neat techniques pictured here that you could use to hold any binocular steadier. I used the “rifle sling” technique pictured on that site with my 15X70s and it helps significantly.

When you are looking at Jupiter’s moons, it’s fun simply because they are constantly changing from night to night – even from hour to hour. It’s also fun because they are surprisingly diverse worlds. In fact, the exploration of large moons throughout the solar system has been a constant source of surprise. So I suggest two things.

First, learn more about Jupiter’s moons by going here. (Pay special attention to the four “Galilean Moons – those are the ones you see.)

Second, use this Javascript utility at Sky and Telescope to figure out which moon is which when you actually observe them..

And while we’re on the subject of handy tools at Sky and Telescope, also use their utility to figure out when it would be a good time to catch the surprisingly elusive Demon Star – aka Algol – when at its minimum. This is something you don’t need binoculars to see – it’s best done with the naked eye. I explained it in more detail last month.

For me, this month that utility shows a couple of good dates – that is, dates when the minimum comes at a reasonable hour for local observing: –

• 11/15/2010 @ 9:41 pm
• 11/18/2010 @ 6:30 pm

Early morning lunacy

I’m marking November 5th on my calendar as a chance to see an extremely thin crescent moon. Now I will be the first to admit this is kind of silly, but it’s also fun and just being up to witness the dawn, hear the birds, and see a brilliant – and incidentally, very thin crescent Venus – are more than enough reason to give this a try, weather permitting.

For me, Venus will be rising at about 6:32 am (49 minutes before sunrise), and a waning crescent Moon just below it (less than 3 degrees) at about 6:44 am. Sunrise is at 7:21, so that means all of this will be taking place in bright twilight – and that means I need to use binoculars. I also need to know where to look and when. My guide will be the bright star Spica. As Venus rises, Spica will be about 7 degrees directly above it at Azimuth 112 degrees. That’s about two fists held at arm’s length south of due east.

If I’m able to catch this Moon, it will be only 18 hours from new – the tiniest slither of a moon I’ve ever seen. As a bonus, viewing Venus in a telescope will show it, too, as a thin crescent. Having passed between us and the Sun, it will become more illuminated each day as it draws away from us, moving faster than us in a shorter orbit. (It will be noticeably higher in our sky each morning as well.) At about -4.4 it will be incredibly bright, so even in the twilight should be easy to see.

However – to see these events you need perfectly clear skies and an unobstructed eastern horizon. When you consider all the odds – clear skies on the morning of such an event, a good location, and the ability to squeeze this into your personal schedule, events such as this are frequently a once-in-a-lifetime thing. Seen that way, they are quite exciting and worth the extra effort.

‘ey Tauro! Aqui!

Yep right here, Tauro. All month you may at any time encounter a Taurid meteor. That’s “Taurid” as in “Taurus the Bull,” so think of them as charging bulls, plummeting across your evening sky. It’s hard to call these an event because we’re really talking about two showers, both of which appear to originate in Taurus and neither of which have a strong peak. Technically the “South Taurids” will peak on November 5 and the “North Taurids” about November 11/12.

But I wouldn’t get too excited about those dates. Personally, I don’t go looking for Taurids. Sitting, staring at the sky to see maybe one or two meteors an hour exhausts my patience immediately. Instead, I just remind myself when doing other observing during November, to take note of any bright meteors I see and see if they can be traced back to the general vicinity of Taurus.

The Pleiades mark the shoulder of Taurus the Bull, and they’re as good a marker for the radiant of the North Taurids as any – roughly speaking. The shower lasts for more than a month – from mid-October to near the end of November. Like all meteors, they are best seen when there is little Moon in the sky, and your chances of seeing any get better as the shower radiant gets higher in the sky – in this case you may see some any time after sunset, but your chances improve right up until about 1 am. They remain good well into the morning hours.

Taurids tend to move slowly and be bright. So if you see a good meteor, see if you can trace it back to somewhere near the Pleaides. If you can, chances are it was a Taurid – part of the dust trail left by Comet 2P/Encke.

Enter the Lion with a Gentle Roar

Now the Leonids are a much different story – they’re a shower with a clear peak.

With the Leonids – a shower named because they appear to radiate from a spot within the constellation of Leo the Lion – you can pick a morning, cross your fingers, and hope for luck – either November 17 or November 18.

The operative word is “morning.” Leo doesn’t put in an appearance until midnight, and there will be a pretty bright Moon right up until a few hours before sunrise. So to get a good solid hour of meteor observing in before the dawn starts to wash them out, pick a morning (Nov. 17 or 18) and check to see when local Moon set is. (You can find a table for your location here.) Your goal is to observe from about when the Moon sets until about one and a half hours before sunrise.

You can look anywhere – just get comfortable, look up, and when you see a meteor, see if it would trace back in the general direction of the bright star Regulus In Leo. If so, it’s a Leonid.

From time to time the Leonids have really been spectacular. But lately they have just been a nice little shower where you can expect to see perhaps half of the Perseids you might see in August. I never see as many meteors as observers at really dark sites. In the case of the Leonids, I would be happy if I averaged one every five minutes or so.

It’s enough, though, to keep me looking up and enjoying the quiet solitude of a morning sky.

Calendar for November

1-18 – Be on the lookout for Taurid meteors!

4 – NASA’s Deep Impact Spacecraft passes within 435 miles of Comet Hartley
2 – look for pictures in the news!

5 – Thin crescent Moon, crescent Venus – just before dawn.

6 – New Moon

7 – Fall back to Standard Time for most of US.

13 – First quarter Moon

15 – Algol at minimum, 9:41 pm EST

17 or 18 – Leonid meteor shower – early morning event.

18 – Algol at minimum, 6:30 pm EST

21 – Full Moon

28 – Last quarter Moon.

Look North in November into the Dragon’s Lair

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

Click here for a printer-friendly version of the above chart.

Our north sky map this month is covering a slightly larger area than normal because I want to capture the relationship between Vega and Capella – two of our northernmost guidepost stars – that anchor the north sky in November. Think of them as two cornerstones and a line drawn between them will go quite close to the North Star, Polaris. What’s more, Vega will help us find the head of Draco the Dragon.

Draco is one of the north sky’s more charming constellations, for its long, slithery form does call to mind a dragon. It’s quite easy to pick out, really, but you do need dark skies. Start by locating Vega. The four stars that mark the head of Draco – one is quite faint – will be found roughly halfway between Vega and the two bright stars that mark the end of the cup of the Little Dipper. Having located the head, you really need a chart handy to find the rest of this long, twisting, dragon body – but it is pretty easy, and once you identify it, you won’t forget it.

Draco also harbors a special treat for binocular and small telescope users. That faint star (Nu) that marks one corner of the Dragon’s head? It’s really two, perfectly matched, 4.9 magnitude stars that are far enough apart so they can be split with binoculars – assuming you have good eyes and a really steady hand. In a small telescope they are absolutely delightful and earn their nickname of Dragon’s Eyes. ( There are actually three neat double stars in this region that are a delight for the telescope user. I’ve written about them in the double star observing blog I share with my friend John Nanson.)

Meanwhile, to the east we have a bright half circle of asterisms we’ve been talking about in the previous months. Start with Capella and move on up to the “Bow” of Perseus and from there higher still to the “W” of Cassiopeia. Directly above the Pole you’ll find the “Home Plate” of Cepheus pointing down towards Polaris.

Look east in November 2010 for the “Eye of Sauron” star and Capella

November brings us our southernmost – and northernmost – guidepost stars, Fomalhaut and Capella. Their positions in the sky mean that for Northern Hemisphere observers Fomalhaut is the guidepost star we see for the shortest amount of time – and Capella is the one we see the longest.

In fact, for many, Capella is visible during some hour every night of the year – and for those north of latitude 45 degrees, it is circumpolar – that is, it never sets. But lonely – and freshly fascinating – Fomalhaut just puts in a relatively brief appearance low to the south.

From NASA:"This image, taken with the Advanced Camera for Surveys aboard NASA's Hubble Space Telescope, shows the newly discovered planet, Fomalhaut b, orbiting its parent star, Fomalhaut. The small white box at lower right pinpoints the planet's location. Fomalhaut b has carved a path along the inner edge of a vast, dusty debris ring encircling Fomalhaut that is 21.5 billion miles across. Fomalhaut b lies 1.8 billion miles inside the ring's inner edge and orbits 10.7 billion miles from its star." Click image for larger version.

Fomalhaut is “lonely” because there are few bright stars in its vicinity. It is “freshly fascinating” because early in this century the Hubble Space Telescope got a fantastic picture of a disc of “debris” surrounding it, showing this young star to be in the throes of forming planets. Then in 2008 scientists announced they had actually found a planet circling Fomalhaut (see photo above), the first planet outside our Solar System to be seen with visible light. Cool! Add to this the fact that the Hubble photograph of Fomalhaut could be easily mistaken for the Eye of Sauron, and for fans of the Lord of the Rings movie triology, Fomalhaut becomes especially memorable. (For more on the “Eye of Sauron” go here.)

Vital stats for Fomalhaut (FO-mal-ought)

• Brilliance: Magnitude 1.16; its luminosity is the equal of 16 Suns.
• Distance: 25 light years
• Spectral Types: A3V
• Position: 22:57:39, -29:37:20°

Click chart for a larger image. (Chart modified from screen shot of Starry Nights Pro software.)

Click here to download a printer friendly version of the above chart.

Finding Fomalhaut

As always, it’s easiest if you start looking in the east 45 minutes after sunset when in the twilight only the brightest stars are visible as shown on our chart. Fomalhaut is the brightest star south of southeast and about a fist and a half above the horizon 45 minutes after sunset. I emphasize “star” because in 2010 Jupiter is in the general vicinity, but significantly brighter, and about three times as high. Trailing well behind Fomalhaut – to the east – and lower still is a second magnitude star (same brightness as the North Star) called Deneb Kaitos. It’s about the same distance from Fomalhaut as Fomalhaut is from Jupiter, and I mention it only so you won’t mistake it for Fomalhaut.

If you have learned the Great Square – see this post – then the two stars that form the western edge of that square can be used, as shown in our chart, as pointer stars. Drawing an arrow through those two stars leads you to Fomalhaut. You could also wait until a couple of hours after sunset when you would find Fomalhaut very close to due south. Even then, from my latitude of 41.5° N it is not quite two fists (19°) above the southern horizon.

Ahhh Capella!

Capella is distinctive because it’s not “a” star – it’s two! But these two, bright, yellow suns are so close together that you’ll always see them as one, even if you use a large telescope. Together they make a star that rivals Vega and Altair, now well into our western sky, in brightness. (See Summer Triangle chart here.) In fact Capella is the third brightest star in the Northern Hemisphere – but that’s a tad deceptive because it doesn’t count Sirius – the brightest star that most Northern Hemisphere observers can see, because technically Sirius is in the Southern Celestial Hemisphere, since it is below the celestial equator. But you don’t have to worry about such technicalities to enjoy a view of Capella. Just look to the far left on the “look east” chart for this month. You will need a very clear horizon, however, especially at the start of the month because then Capella will not even be one fist above the horizon.

Just as Fomalhaut is a bit south of southeast, Capella is a bit north of northeast.

It’s easiest to find Capella if you start 45 minutes to an hour after sunset. Choose a spot with a clear horizon to the northeast and watch for a bright star to appear very near the horizon. Like all bright stars near the horizon, Capella will twinkle and flash in different colors because you are seeing it through a lot of atmosphere. It won’t show its soft, golden hue until it is much higher in the sky. Even a veteran skywatcher can be fooled by this. Recently my wife was looking to the northeast on a fall evening and saw what she thought was Capella. But it was so bright and blinking red and green so distinctly, that she changed her mind and decided it was an airplane! (There’s an airport off in that general direction.) When after a minute or so it hadn’t moved, she knew her first thought was correct – but boy it made a convincing airplane!

For me, Capella marks a graceful arc of bright stars and asterisms that circle the north celestial pole. If you have been following these directions for a few months, look at Capella, the Bow of Perseus, and the “W” of Cassiopeia to see what I mean. Watching these move in the course of a single night – or from month to month – always gives me a real sense of how, from our vantage point, all the stars appear to circle Polaris.

As mentioned, Capella is really a complex multiple star. Its two main components are both yellow giants dubbed Aa and Ab, but there are two more stars in this family. However, they are a pair of red dwarfs only visible in a telescope and are so far away from the two bright stars that they take more than 1,000 years to complete an orbit. The two bright stars orbit in just 104 days. James B. Kaler, in his book The Hundred Greatest Stars, says this about the Capella twins:

These two magnificent giants are separated by about the distance between Venus and the Sun. A resident on a ‘Jupiter’ ten times further out would see two ‘Suns’ about half a degree across (similar to the Sun in our own sky), separated at maximum by some 6 degrees, one setting right behind the other.
So when you find Capella, pause – picture yourself on the Jupiter-like planet with these twin yellow Suns in your sky!

Vital stats for Capella (kah-PEL-ah)

• Brilliance: Magnitude .08; its luminosity is the equal of 16 Suns.
• Distance: 42 light years
• Spectral Types: G8/G0
• Position: 05:16:41, +45:59:53

Still with us!

Other bright guide stars and asterisms introduced in previous months that are still readily seen include the Summer Triangle of Altair, Deneb, and Vega, which is high over head and crossing into the western sky. Arcturus is just above the horizon in the west, the Big Dipper just west of north and hugging the horizon, and the Teapot is diving into the ground in the southwest. And, of course, we have the “Bow” of Perseus with “Algol” the “Demon” star, the “W” of Cassiopeia, the “home plate” of Cepheus, Andromeda’s Couch, and the Great Square.