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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.

June 2010 events: A month of surprises involving Jupiter, a comet, and maybe even some meteors!

Note: While many of the following events are visible throughout the world, the exact time and location in the sky can be dependent upon your latitude and longitude. Since I’m in the mid-northern latitudes (41.5N, 71.1W), specifics, where place-and-time-dependent, are calculated for this location.

Observing Jupiter and Uranus

June promises to be full of surprises, most revolving around getting up early to enjoy a summer dawn! I’m circling the weekend of June 12-13 on my calendar as special in terms of getting up early, and I’m hoping for a triple header: viewing Jupiter, finding Uranus, and seeing Comet McNaught. For the meteors, it will be June 23 and in the evening – though there’s a real big question mark around this event. Let’s start with a sure thing – Jupiter and Uranus.

You can’t miss Jupiter. It’s the brightest “star” in the southeast in our morning sky. You can easily miss Uranus. It’s barely naked eye visibility in the best – least light-polluted – locations and hard to pick out from true stars in the area. But on a morning in June finding Uranus should be an easy task with any decent pair of binoculars because Jupiter will guide you right to it.

It’s Jupiter that offers our first surprise for those who can turn a small telescope on it. Usually even the most modest telescope will show you two dark belts on Jupiter – but this June there’s no telling Jupiter missing bandexactly what you’ll see. Jupiter’s been hiding behind the Sun recently, but when it emerged in May it surprised planetary observers by displaying just one of its major trademark dark bands. The other had vanished!

If you have a small telescope and point it towards Jupiter on a June morning will you see it this way? Can’t say. That’s why it will be a surprise. Veteran observers think the second band could come back quite quickly – in just a week’s time, for example. They say this sort of thing is rare but has happened before. One theory is that high, thin, light-colored clouds are covering the band, and these clouds may vanish without warning – just as they appeared without warning.

Jupiter is second only to Saturn in its appeal to small telescope users, not only because of its bands, but because of the constant dance of its four Galilean Moons, which you can detect if you can manage to hold even modest binoculars, such as 10X50s, steady. And Jupiter this year will be doing an even grander dance with its outer cousin, Uranus. The two gas giants come quite close to one another – as viewed from Earth – three times in the next seven months, the first being in June. That means Uranus, usually a difficult object to find because it is so faint, will be an easy target for binocular and small telescope users – though its disc is so small it will hardly show except in a telescope at high power.

Here are a couple of images giving you the position of the two planets early in the month and near the end of the month.

jupiter_uranus_2010

Click image for a larger view. Image developed from "Starry Nights Pro" screen shot.

For a printer-friendly version of the appropriate chart for on or near June 6, 2010, click here.

For a printer-friendly version of the appropriate chart for on or near June 30, 2010, click here.

A good project would be to take the print out of the first chart (June 6) and mark the position of each planet when observed about once a week. You’ll notice that both drift to the east (left) against the background of stars, but Jupiter’s progress appears much faster because it is so much closer to us. That would help you appreciate the fact that when Uranus was discovered March 13, 1781, by the English astronomer William Herschel, it effectively doubled the size of our solar system! (And if you don’t want to get up early several mornings to actually see this, just study the charts above, but be sure to click on them to see the larger version. 😉 For more on Uranus see the May events entry.

The two planets come closest on June 8 when they are less than half a degree apart. However, any time during the month they will easily fit in the same binocular field of view. I’m aiming for observing on or near the 12th simply because it’s a weekend, and since there’s no Moon in the sky to drown things out with its glare, that will also be a good time to spot the comet.

Seeing Comet McNaught at its best

Comets are notoriously unpredictable and catching them at their best is a game you play, trying to balance the time when the comet is close to the Sun – and thus usually brightest – against the approach of dawn, which lightens the sky behind the comet as it gets closer to the Sun and thus makes it more difficult to see.

Northern hemisphere observers are overdue for a nice comet and McNaught (C/2009 R1) could be it. Astronomy magazine thinks it may reach naked-eye brightness with a distinct tail. Sky and Telescope seems a bit more cautious in its prediction, but still thinks it will be very nice in mid-June. In 2007 another Comet McNaught (C/2006 P1) put on an absolutely spectacular display for southern hemisphere observers, becoming the brightest comet in 40 years seen from anywhere on Earth. Sadly, for those in mid-northern latitudes the show was nowhere near as good and was so brief many missed it. I was lucky to catch it, but against strong twilight, so it didn’t show at its best. I took this shot of Comet McNaught over Horseneck Beach in Westport on January 11, 2007.

McBaught_2007

Bren and I saw an earlier Comet McNaught in strong twilight and amidst clouds in 2007 shortly after sunset.

A recent study, however, has found that Comet McNaught was not only a spectacular sight from the southern hemisphere, but also probably the largest comet on record.

It’s fairly safe to say this Comet McNaught will not be nearly as spectacular – but it could be quite nice, especially in binoculars, and it should be easy to find as it will be going past some well-known stars. In fact on the morning of the 12th it will be right between Algol (the Demon Star) and Mirfak, brightest star in the constellation Perseus. Here’s a chart – but take the show of the comet’s tail as simply a rough indicator of the tail’s direction. I doubt it will be this large. (Starry Nights software, from which this chart was derived, shows all comet tails about the same length.)

Comet McNaught 2010

Click image for larger version. Chart derived from "Starry Nights Pro" software.

For a printer-friendly version of this chart, click here

As with the Jupiter/Uranus event, Comet McNaught should be visible much of the month. But early in the month it will be dimmer, and later in the month it will be so close to the Sun that the dawn twilight will drown it out. The middle of the month seems like the best bet for catching the comet when it’s quite bright and will be high enough in the sky to see well during a time period when the sky behind it is fully dark.

The beginning of astronomical twilight is when the sky starts to brighten and continues to do so right up through sunrise. For my area – and other mid-northern latitudes – astronomical twilight starts about 3 am in mid-June, more than two hours before sunrise. (Tables for astronomical twilight times for your area can be easily created at the U.S. Naval Observatory site here.) My plan, weather permitting, is to go out on Saturday morning, June 12, to a local observing sight that has a beautifully clear and dark eastern horizon, and to be there by 2:30 am EDT. That will give me an opportunity to see Comet McNaught when it is about 15 degrees above the northeastern horizon. I expect to have a good view right up through 3:30 am – after that I expect the interference from the approaching dawn to become serious. (That’s the date of new Moon, so it will offer no interference for several days either side of this date.)

But again, comets just aren’t that predictable. Back in 1973 I published a cover story in Popular Science quoting experts who predicted that Comet Kohoutek would be the “comet of the century.” It was no such thing and I was embarrassed! And the most exciting comet of recent years for me was Comet Holmes in 2007, which suddenly – and inexplicably – broke into naked eye glory when no one was expecting it to do any such thing.

What can be done with accuracy is to predict when and where you can expect to see Comet McNaught. Those predictions you can trust. And you should begin your search with the naked eye, but I suspect binoculars will give you your first view, and it may take a small telescope to give you a really decent look at it.

Addendum:

  • For an orbit diagram of the current Comet McNaught see this page.
  • This Comet McNaught is the 56th comet discovered by this man. Why so many? Well, for the past five years or so it’s been his job to find comets  that may pose a threat to Earth and he has the tools to do it. Go here to learn more.

Catching the elusive Bootid meteors

If anything in amateur astronomy seems riskier than making predictions about comets, it’s making predictions about meteor showers – especially unusual ones that flare up on rare occasions. But Astronomy magazine is carrying a prediction that on the night of June 26 – and we’re talking the more comfortable evening hours now – we could get quite a display.

It reports that the International Meteor Association predicts that the peak of this shower could occur on June 23/24 between 7 pm and midnight EDT. Well, of course that means this favors the East Coast and even then, it may peak while it is still light, since you won’t have complete darkness until after 10 pm.

Frankly, I’m very skeptical about this one, but if it’s clear that night I’ll do some observing of double stars and keep an eye out for meteors at the same time. The problem is simple: at 10 pm the Moon, just a couple of days short of full, will be low in the southern sky, but still high enough so I think it will drown out many of the meteors. So what we have here is a prediction that a normally quiet “shower” may suddenly have a real outburst worth seeing – but that outburst could come during daylight or twilight, and if it comes during full darkness it will be competing with bright moonlight. That just doesn’t seem all that promising. But then, what can you lose being out on a warm June evening with clear skies, bright moon, and and fireflies? And now you know you may get lucky and see some bright meteors as well – maybe a whole lot of meteors 😉

June’s Calendar – a chronology and review

You have the highlights above – here’s a summary of them, along with some additional June events, in chronological order.

  • June 4 – Last quarter Moon
  • June 5,6,7,8 – Watch Mars pass close to Regulus – note color difference! (Mars is just a tad brighter.)
  • June 6 – Good time to start your search for Uranus and Comet McNaught
  • June 12 – New Moon – prime weekend for an early morning expedition to see Jupiter, Uranus, and Comet McNaught
  • June 14 – Brilliant Venus just above a thin crescent Moon – nice!
  • June 19, 20 – Venus is just 1 degree from the Beehive – use binoculars to see the stars near this most brilliant planet.
  • June 21 – The Summer Solstice – and shortest night of the year. Comet McNaught should be getting quite difficult to see by now.
  • June 23 – Cross your fingers and hope for some spectacular meteors appearing to radiate from Bootes still high in the evening sky.
  • June 26 – Full Moon – and a partial lunar eclipse in the morning sky for folks in western North America and points west.
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