Posted on by Tammy Plotner

Observing Spotlight – Dropping In On Jupiter…

Parallel/Cross-Eye 3D Image - Click For Full Size

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“Now that she’s back in the atmosphere, with drops of Jupiter in her hair…” Oh! Hey, there! Come on over and have a seat. Yeah, I really like that “Train” song, too. While the Moon is putting the brakes on deep sky observing, why don’t you take a look though the magnificent eye of the 9″ TMB refractor of Dietmar Hager and we world-wide friends can spend a little quality time together with Jupiter.

Here… You look through the eyepiece of a little telescope for awhile and I’ll tell you some of the things we know about this giant planet.

What’s that you say? Yes. Jupiter is big… Big enough to hold the mass of 1,000 Earths and about 1/10 the size of our Sun. Its a heavy-weight, too… But, believe it or not, Jupiter’s density is only about 1/4 of that of Earth’s. Scientists think this means the giant planet consists mostly of hydrogen and helium around a core of heavy elements. That means Jupiter more closely resembles a sun instead of a planet! Yeah… It’s hot there, too. As a matter of fact, Jupiter is putting out twice as much heat as it receives from Sol. Near the core temperature may be about 43,000 degrees F (24,000 degrees C)… Even hotter than the surface of the Sun. Hot enough to get a burn? Darn right. Those subtle tones of red and brown are chemical reactions much like what happens when we humans get a sunburn.

I see you smiling in the dark. Are you starting to notice details Jupiter’s cloud bands? Even a small telescope shows these areas called “zones”. This is where chemicals have formed colorful layers of clouds at different heights. The white belts are made of crystals of frozen ammonia and they are positioned much higher than the dark belts. Of course, you know all about the “Great Red Spot”, but sometimes it’s pretty hard to see unless you know when to look. Jupiter makes a complete rotation in about 10 hours, so even if you can’t see something right now – you can wait awhile and it will come around.

Speaking of coming around, did you notice how close one of Jupiter’s moon is getting to the edge of the planet? Then keep watching because we’re about to see a transit happen. Jupiter has at least 60 moons, but 4 of them are bright and very easy to see even in binoculars. They were discovered by Galileo, and that’s why you’ll sometimes hear them called the “galiean moons”. When they zip around behind Jupiter in their orbit, it’s called a occultation – but when they go in front of the planet from our point of view, it’s called a tranist. The really fun part is that you can not only see the little moon going across the surface, but a few minutes later? You can see the shadow, too! Here’s a little bit of magic from another friend of ours named Sander Klieverik.

Click to start animation...

Isn’t that just the coolest? You’re going to be hearing a lot about Sander’s work here in the near future. And there’s going to be a great Jupiter event he wants to make sure you know about!

“On October 31, 2010 Europa and Ganymede will simultaneously cross the cloud tops of Jupiter from 02:26 till 03:21 UT as do their shadows from 04:17 UT till 07:00 UT. Timing of entrance of the first moon, Ganymede will be around 00.20 UT, following by Europe at 02:26 UT. The first shadow will appear 04:09, quickly followed by Europe’s shadow at 04:16. Two shadows in very close proximity should be a very beautiful view! Circumstances are favourable as Jupiter has a visual diameter of around 48 arc seconds, being a month after opposition in which Jupiter reached almost 50 arc seconds (minimum 33″). For the non-astronomers, when a planet is in opposition it is roughly closest to the Earth at this point of its orbit, making it appear bigger and brighter. At that moment it is visible almost all night, rising around sunset, culminating around midnight and setting around sunrise.”

In the meantime, why don’t you keep practicing timing galiean events and seeing them? Here’s a handy Jupiter Moon Tool, and Sander has also prepared a Jupiter Almanac as well!

“But tell me, did the wind sweep you off your feet? Did you finally get the chance to dance along the light of day… And head back to the Milky Way? And tell me, did Venus blow your mind? Was it everything you wanted to find? And did you miss me 1hile you were looking for yourself out there?”

Now, quit bogarting that eyepiece… It’s my turn!

Many thanks to the one and only Dietmar Hager, Jupiter Video courtesy of Northern Galactic and the up and coming Sander Klieverik’s “AstronomyLive”. Song lyrics – “Drops of Jupiter” are from the artists “Train”. Let’s keep on rockin’ the night!

Posted on by Tammy Plotner

Astrophotography Spotlight – Centaurus A

“I’m on rhe outside… I’m lookin’ in.” And just who are we looking in at this time? None other than the familiar face of Centaurus A.. The stunning, turbulent dust lane is cloaked in the ethereal mist of living galaxy stuff – the result of a gravitationally hungry elliptical galaxy drawing a smaller companion spiral galaxy towards its demise. Like a spider waiting in the center of a web, the black hole at the heart of NGC 5128 takes no prisoners. Its complexity screams out to us in radio, X-ray, and gamma-ray energy. “I can see through you… See the real you.”

It waits in space some 10 to 11 million light years away. It’s the nearest active galaxy to Earth and contains a core black hole estimated to be a billion times the mass of our Sun. The result of Centaurus A’s merger event is so incredibly powerful that it may have even shifted the axis of the massive black hole from its expected orientation – an area not much larger than our own solar system. “The variability of the nucleus may represent the accretion of individual stellar or cloud remnants onto the black hole triggering renewed jet activity and fueling the radio source.” says F.P. Israel. “Details of these processes are not clear yet, but careful and frequent monitoring of Centaurus A at radio, X-ray and -ray wavelengths may provide important information. For instance, how does the nucleus drive the nuclear jets, and how are the relativistic nuclear jets transformed into the nonrelativistic inner jets? The circumnuclear disk does not seem capable of controlling the collimation of the nuclear jets, but its orientation exactly perpendicular to these jets, suggests that it is somehow connected with the collimating agent.”

Could it be the unique properties of Centaurus A originate from its cannibalizing an equally unique galaxy? If you examine the full size image by Ken Crawford you’ll find many background galaxies hidden amongst the stars. What we may very well be viewing is the early results of an giant elliptical merging with a much small spiral structure – creating a stunning halo. “When most people think of NGC 5128 (also known as Centaurus A) they see radio jets, central black holes, a very visible accretion disk and more. But these are “icing on the cake” of the underlying giant E galaxy.” says Gretchen Harris (University of Waterloo). “We now know the it has a fairly normal old halo system as seen in its globular clusters, planetary nebulae, and red giant stars. Its proximity makes NGC 5128 an ideal template for understanding the properties of large E galaxies in general.”

While science may consider Centaurus A to be a template, its tortured form makes it an incredible palette to the eye of the camera. Utilizing a RCOS 14.5″ Truss telescope and taking various exposures for nearly two hours, Ken has produced an image which reveals intricate details almost as fine as the 7 light-year resolution photos taken by the Hubble Space telescope.

Here you will see clumps of hot, young blue stars which have newly formed and the pink signature of star forming regions – as well as the release of gas which hasn’t conformed to the spin axis of the central black hole. Maybe two black holes duking it out? “This black hole is doing its own thing. Aside from receiving fresh fuel from a devoured galaxy, it may be oblivious to the rest of the galaxy and the collision,” said Ethan Schreier of the Space Telescope Science Institute. “”We have found a complicated situation of a disk within a disk within a disk, all pointing in different directions. It is not clear if the black hole was always present in the host galaxy or belonged to the spiral galaxy that fell into the core, or if it is the product of the merger of a pair of smaller black holes that lived in the two once-separate galaxies.”

Although the galactic merger may have began around 200 to 700 million years ago, the incredible arcs of multi-million degree gas remain in a 25,000 light-year diameter wobbling ring producing high energy jets. Given its size and location this ring might very well be a galaxy-sized shockwave – the million mile per hour outward ripples of an intense explosion which may have occurred some 10 million years ago. “We believe that most of these stars formed from the interaction of the jet with local concentrations of dust and gas.” says John Graham. “The brightest blue stars are presumably the youngest stars and tend to lie close to the X-ray jet. We suggest that the raw material for star formation is found in dust patches of small angular size in the area and that star formation is triggered by shocks initiated by the jet.”

Now I want you to take a closer look. What you are going to discover (highlighted by the small arrow) is a thin, blue smear of newly formed stars. It’s something you’d probably never notice unless it was pointed out to you.

What you are seeing is a thousand light year long band of scar tissue. A dead giveaway of a recent galactic absorption. Astronomers had previously noticed the arc now identified as a galactic merger remnant, but without recognizing its origin. “This adds a nice example in the local universe to the growing evidence that galaxy halos are built up from the accretion of dwarf satellite galaxies,” said Eric Peng, a graduate student in astronomy at Johns Hopkins University. “These halos are interesting partly because they’re hard to study, but also because time scales for things to happen in halos are very long, which means they may preserve conditions that reveal how a galaxy formed and evolved.”

But for now? “I’m on the outside… And I’m lookin’ in. I can see through you… See your true colors.”

Many thanks to Ken Crawford for his exquisite work which led to a wonderfully pleasant day of researching the ins and outs of a most remarkable galaxy!

Posted on by Tammy Plotner

Clockwork Planets

Bottoms up! Mercury, Moon, Saturn, Venus, Mars...

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While the Perseid meteor shower has been putting on quite a show, there’s an awesome “no telescope needed” eye-catching apparition that only requires a clear western skyline. If you haven’t been watching the planets – Mercury, Saturn, Venus and Mars – line up like clockwork, then don’t despair. You have a few more days yet!

While the uniformed all-too-often see “signs of bad portent” in a planetary alignment, the rest of us know this is a perfectly normal function of our solar system called a conjunction. This is a simple positional alignment as seen (usually from Earth’s viewpoint) from any given vantage point. The world isn’t going to end, the oceans aren’t going to rise… and Mars is darn-sure not going to be the size of the Moon. All alignments of at least two celestial bodies are merely coincidental and we even have a grand name for what’s happening – an appulse.

When planets are involved, their near appearance usually happens in the same right ascension. They really aren’t any closer to each other than what their orbital path dictates – it just appears that way. In the same respect, there is also conjunction in ecliptical longitude. But, if the planet nearer the Earth should happen to pass in front of another planet during a conjunction it’s called a syzygy!

One thing is for sure… You don’t have to be a syzy-genius to simply enjoy the show and the predictable movements of our solar system. Just find an open western skyline and watch as twilight deepens. Tonight the Moon will be directly south of Venus and over the next couple of days the planetary alignment will gradually separate as brilliant Venus seems to hold its position, while Mars, Saturn and Mercury drift north. Enjoy the show! Because just like the yearly Mars/Moon Myth?

It happens like clockwork…

Many, many thanks to the incredible Shevill Mathers for providing us with this breathtaking photo. (Do you know just how hard it is to get a shot like that without over or under exposing? I dare you to try it…) Every fox has a silver lining!

Posted on by Tammy Plotner

2010 Perseid Meteor Shower


In just a few days – during the evening hours of August 12 and morning of August 13 – one of the year’s most reliable meteor showers is about to grace this year’s dark skies. Not only will we be in for some celestial fireworks, but the planets are going to put on a show as well. Who, what, when, where, why and how? Then step inside and let’s talk about the 2010 Perseid meteor shower…

During the latter half of July and the beginning of August, the Earth cruises through several minor cometary debris streams – producing equally minor meteor showers which meander through the constellations of Cygnus, Capricornus and Aquarius. This is the type of normal activity which is enjoyed by both the northern and southern hemisphere. One any given good, dark night, you might spot as many as a dozen meteors during an evening’s observing session. It’s a nice transition in the weather for both halves of Earth and this period of time makes for comfortable watching. While I love catching a sparkling trail when I really wasn’t expecting or waiting for one, there’s nothing in the heavens that can make me yell out loud like being witness to a productive meteor shower.


And the Perseids produce…

Where exactly did all the “stuff” come from that causes the annual Perseid meteor shower to be so reliable? Try periodic comet 109P/Swift-Tuttle. Discovered in 1862, Swift-Tuttle is called “periodic” because it makes a pass through our solar system about every 133-135 years leaving behind a debris trail. As early as 36 AD, Chinese astronomers began to notice a sharp peak of meteor activity during this time and began keeping record. Other astronomers followed suit until astronomy became a rather dangerous occupation and facts and figures began to dwindle. Although often referred to as “the tears of St. Lawrence” to celebrate the martyr’s death on August 10, it wasn’t until 1835 and Adolphe Quetelet that the annual Perseid was actually given credit to an individual for pinpointing its radiant and peak date.

Within four years, sharp-eyed observers had not only began to note the Perseid presence, but to make an accurate hourly account of the fall rate as well. In 1839, E. Heis gave us his first written documentation of a maximum rate of 160 per hour and over the next several decades, many other observers joined him. What they noticed through their observations was the fall rate changed from year to year… Why?

Between 1864 and 1866, Giovanni Schiaparelli also took an interest in the Perseids and computed the stream’s orbit. What he discovered was astounding. It nearly matched that of a comet discovered just two years earlier – 109P/Swift-Tuttle. After that, it didn’t take very long to figure out each high spike in fall rates also corresponded with the comet’s known perihelion. It was the very first time a meteor shower had been positively identified with a comet!

But, when it comes to science, proving a speculation is everything. Record keeping for that period of time wasn’t exactly the best and in 1973 astronomer Brian Marsden was busy trying to predict the return of comet Swift/Tuttle. His chosen date was 1981 and as annual activity of the Perseid meteor shower increased, so did the excitement of recapturing the comet. However, like so many astronomical predictions, the traveler from Oort Cloud failed to make its debut appearance Needless to say, between disappointment and lunar interference, interest in the Perseid’s cometary originator quickly faded. However, Marsden wasn’t about to give up. Choosing another documented comet seen in 1737, he made another prediction… Swift/Tuttle would return in 1992.

This time was sweet success.

With 18 years between now and comet Swift/Tuttle’s last perihelion, will the 2010 Perseid meteor activity be a smashing shower or a dwindling display? It’s really hard to say because the stream is so wide and complex. We know when the Earth passes through this outgassing of materials that we can expect a certain amount of activity during a marginal time period – but we can only make a guess at how much material was expelled. There may have been time centuries ago when the comet did something very unexpected (as comets have a way of doing) and left a dense cloud just waiting for us to orbit through… And it may be burning itself out during each successive pass around Sol. So many things can happen! Jupiter may have affected the stream’s position – or a huge flurry of activity might occur during daylight. But what about this year?

Thankfully there will be no Moon to obscure fainter meteors and zenith hourly rates may approach up to nearly 100 per hour. But that’s a very optimistic estimate since the Perseids are notoriously fast – burning through our atmosphere at 140,000 mph – and sometimes very faint. As the evening begins, facing east/northeast will be best for most northern hemisphere observers, and follow Perseus to the north as it rises. Unfortunately, southern hemisphere observers aren’t likely to see any of this activity – but it never hurts to keep watch to the northern horizon if you’re out. If you have to be selective about the times you watch, the very best views will be had when the constellation is at its highest – after local midnight through local dawn.

Don’t wait until the peak date to begin your observations. Perseid activity is already underway at 15 to 20 per hour and the fall rate will only continue to increase as it nears the night of August 12/13th when up to 75 meteors may grace the starry skies. If you live in a light polluted area, make plans to get rural. Many farmers and home owners in the countryside are more than happy to grant you permission to choose a safe observing spot on their land if you explain what you’re doing – so ask! Be sure to take along things which will aid in your comfort, such as a reclining lawn chair or blanket (meteor neck sucks). Make it a popcorn and soda family event! But stay away from white light. If being in the wild scares you a bit, create your own “night vision friendly” flashlight by stretching a red balloon over the lens. If you arrive at sunset? Then check out the beautiful conjunction of Mercury Mars, Saturn, Venus and the very tender crescent Moon….

Wishing you clear skies and the very best of luck!

Here’s information on the 2009 Perseids.

Posted on by Tammy Plotner

Observing Spotlight – Whatever Happened to M71?

The M71 Globular Cluster, as pictured by the Hubble space telescope. Credit: NASA

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In our rush to look at the bright and beautiful objects in the night, we often overlook celestial curiosities in favor of a more splashy neighbor. How many times have you looked at the Andromeda Galaxy, but really didn’t take the time to power up and study M110? Perhaps you spent a whole evening studying the intricacies of the Great Orion Nebula – but totally forgot about striking M78? It’s the way of things. But, next time you drop by the Dumbbell Nebula, spend some Hubl time with the sparkling stars of Messier 71…

Discovered by Philippe Loys de Cheseaux in 1746 and researched by Charles Messier then added his catalog of comet-like objects in 1780, this brilliant globular cluster let’s its presence be known at a distance of about 12,000 light years away from Earth. Covering an area measuring approximately 27 light years across, it shines with a luminosity of around 13,200 suns – not bad for a conglomeration of stars which could be as old as 9-10 billion years. Until about four decades ago, Messier 71 was believed to be a dense galactic cluster – nearly devoid of RR Lyrae “cluster” variable stars and rich in metallicity.

And a concentrated cluster of stars it stayed until modern H-R diagram photometry picked up a short “horizontal branch” in its structure…

Who remembers to stop and study? While grandiose images like our Hubble lead-in photo might pique your curiosity for a moment, it’s the deep sky dedication and devotion revealed in the work of Bernhard Hubl which ignites the sense of wonder all over again…

M71 by Bernhard Hubl

Reach out and touch M71 for yourself. Located in the constellation of Sagitta at RA:19h 53m 48s Dec: +18°47′ and close to magnitude 7, it’s easily caught in average binoculars from a dark sky location, beauty revealed in smaller telescopes and breathtakingly resolved in large aperture telescopes. It’s really not hard to find if you just take the time to let your eyes relax to see Sagitta’s faint arrow-shaped signature asterism. Just aim mid-way between Gamma and Delta and be swept away…

Because it’s full of stars.

Many thanks go to Bernhard Hubl of Northern Galactic for his untold hours of work just to share the inspiration!

Posted on by Tammy Plotner

Gravitational Lensing Caught By Amateur Telescope

Just a few short years ago, even the thought of capturing an astronomy anomaly with what’s considered an “amateur telescope” was absolutely unthinkable. Who were we to even try to do what great minds postulated and even greater equipment resolved? I’ll tell you who… Bernhard Hubl. Come on inside to meet him and see what he can do!

One of the first great minds to consider the effects of gravitational lensing was Orest Chwolson in 1924. By 1936, Einstein had upped the ante on its existence with his theories. A year later in 1937, the brilliant Fritz Zwicky set the idea in motion that galaxy clusters could act as gravitational lenses. It was not until 1979 that this effect was confirmed by observation of the so-called “Twin QSO” SBS 0957+561… and now today we can prove that it can be observed with a 12″ telescope under the right conditions and a lot of determination.

Bernhard Hubl of Nussbach, Austria is just the kind of astrophotographer to try to capture what might be deemed impossible. “Abell 2218 is a galaxy cluster about 2.1 billion light-years away in the constellation Draco. Acting as a powerful gravitational lens, it magnifies and distorts galaxies lying behind the cluster core into long arcs, as predicted by the General Theory of Relativity.”

Say’s Berhard, “I wanted to know, if I could detect signs of these arcs with a 12″ Newtonian at f=1120mm. After over 12 hours of exposure time under excellent conditions, I know that this is a hard job, but I am glad that I could identify the three brighter arcs.”

And so are we!

Many thanks to Bernhard Hubl for his outstanding sense of curiosity and excellent astrophotography… and to the NorthernGalactic community for the heads up!

Posted on by Tammy Plotner

Weekend SkyWatcher’s Forecast: July 16-19, 2010

Greetings, fellow SkyWatchers! Are you ready for a rock the night weekend? Then come along as you won’t need a telescope to watch the movement of the planets and the Perseid meteor shower heating up your evenings! If you’d still like a challenge, then why not chase bright asteroid Ceres with binoculars – or look up a challenging globular cluster? If you still need appeal, then there are a couple of great stars that are worth observing… and learning about! Whenever you’re ready, I’ll see you in the backyard….

July 16, 2010 – Today celebrates the 1746 birth of Giuseppe Piazzi. Although we know Piazzi best for his discovery of the asteroid Ceres, did you know he was also the first to notice that 61 Cygni had a large proper motion? Nine days and 38 years later, the man responsible for measuring 61 Cygni, Friedrich Bessel, was born.

This would indeed be a great evening to check out asteroid Ceres for yourself. You’ll find it in Ophiuchus and well placed for either binoculars or a small telescope just above the “sting” of the Scorpion! Here’s a map to help you along the way…


Now let’s take a look at gorgeous 61 Cygni. You’ll easily locate it between Deneb and Zeta on the eastern side. Look for a small trio of just visible stars and choose the westernmost (RA 21 06 54 Dec +38 44 44). Not only is it famous because of Piazzi and Bessel’s work, but it is one of the most noteworthy of double stars for a small telescope. Of the unaided visible stars, 61 is the fourth closest to Earth, with only Alpha Centauri, Sirius, and Epsilon Eridani closer. Just how close is it? Try right around 11 light-years.


Visually, the two components have a slightly orange tint, are less than a magnitude apart in brightness, and have a nice separation of around 30″ to the south-southeast. Back in 1792, Piazzi first noticed its abnormally large proper motion and dubbed it the ‘‘Flying Star.’’ At that time, it was only separated by around 10″, and the B star was to the northeast. It takes nearly seven centuries for the pair to orbit each other, but there is another curiosity here. Orbiting the A star around every 4.8 years is an unseen body that is believed to be about 8 times larger than Jupiter. A star—or a planet? With a mass considerably smaller than any known star, chances are good that when you view 61 Cygni, you’re looking toward a distant world!

July 17, 2010 – This date marks the 1904 passing of Isaac Roberts, an English astronomer who specialized in photographing nebulae. As an ironic twist, this is also the date on which a star was first photographed at Harvard Observatory!

Tonight let’s have a look at a real little powerpunch globular cluster located in northern Lupus—NGC 5824. Although it’s not an easy star hop, you’ll find it about 7 degrees southwest of Theta Librae, and exactly the same distance south of Sigma Librae (RA 15 03 58 Dec –33 04 04). Look for a 5th magnitude star in the finderscope to guide you to its position southeast.


A Class I globular cluster, you won’t find any others that are more concentrated than this. Holding a rough magnitude of 9, this little beauty has a deeply concentrated core region that is simply unresolvable. Discovered by E.E. Barnard in 1884, it enjoys its life in the outer fringes of its galactic halo about 104 thousand light-years away from Earth and contains many recently discovered variable stars.

Oddly enough, this metal-poor globular may have been formed by a merger. Research on NGC 5824’s stellar population leads us to believe that two less dense and differently aged globulars may have approached one another at a low velocity and combined to form this ultra-compact structure. Be sure to mark your observing notes on this one! It also belongs to the Bennett catalog and is part of many globular cluster lists.

July 17, 2010 – Celestial scenery alert! Are you watching the planet dance as Mars heads towards Saturn? You don’t need a telescope to enjoy the early evening trio of bright Venus along the western horizon – or the duet just above it! While you’re out enjoying a relaxing evening, keep your eyes on the skies. The early activity of the annual Perseid meteor shower is really heating up and you can expect to see several “shooting stars” an hour!


Tonight let’s begin with the 1689 birth of Samuel Molyneux. This British astronomer and his assistant were the first to measure the aberration of starlight. What star did they choose? Alpha Draconis, which oscillated with an excursion of 39’’ from its lowest declination in May. Why choose a single star during an early dark evening? Because Alpha Draconis—Thuban—is far from bright.


At magnitude 3.65, Thuban’s ‘‘alpha’’ designation must have come from a time when it, not Polaris, was the northern celestial pole star. If you’re aware that the two outer stars of the ‘‘dipper’’ point to Polaris, then use the two inner stars to point to Thuban (RA 14 04 23 Dec +64 22 33). This 300-light-year distant white giant is no longer main sequence, a rare binary type.

Now head to binary Eta Lupi, a fine double star resolvable with binoculars. You’ll find it by staring at Antares and heading due south two binocular fields to center on bright H and N Scorpii— then one binocular field southwest. Now hop 5 degrees southeast (RA 16 25 18 Dec –40 39 00) to encounter the fine open cluster NGC 6124. Discovered by Lacaille, and known as object I.8, this 5th magnitude open cluster is also Dunlop 514, Melotte 145, and Collinder 301. Situated about 19 light years away, it shows a fine, round, faint spray of stars to binoculars and is resolved into about 100 stellar members to larger telescopes. AlthoughNGC6124 is low for northern observers, it’s worth the wait to try at culmination. Be sure to mark your notes because this delightful galactic cluster is also a Caldwell object and counts for a southern skies binocular award.

Until next week? Keep capturing photons!

This week’s awesome images are (in order of appearance): 61 Cygni, NGC 5824, Alpha Draconis and NGC 6124 are from Palomar Observatory, courtesy of Caltech. Maps are courtesy of “Your Sky”. We thank you so much!

Posted on by Tammy Plotner

Bright Outburst of QZ Virginis In Progress…


According to AAVSO Special Notice #212: “Hiroshi Matsuyama (MTH), Kanimbla, Queensland, Australia, reports and Rod Stubbings (SRX), Tetoora Road, Victoria, Australia, confirms that the SU UMa-type dwarf nova QZ Vir (formerly called T Leo) is in outburst, and possibly in superoutburst.”

Matsuyama reported it at visual magnitude 10.4 on July 9.409 UT (JD 2455386.909), and Stubbings at visual magnitude 10.0 on July 11.384 (JD 2455388.884).

According to observations in the AAVSO International Database, the last regular outburst of QZ Vir, which is 16th magnitude at quiescence, occurred 4 July 2009 (JD 2455017, magnitude 10.6, Matsuyama), when it reached visual magnitude 10.3 and faded to 15th magnitude by 9 July (2455022). The last superoutburst (see AAVSO Special Notice #144) occurred between 19 January 2009 (JD 2454851, magnitude <14.0, Stubbings) and 21 January 2009 (JD 2454853, 10.97V, R. Diethelm, Rodersdorf, Switzerland), when it reached magnitude 10.0 and returned to 16th magnitude by 1 March 2009 (2454862). If it is a superoutburst, superhumps will develop. All observations, including both visual estimates and CCD time-series photometry, are strongly encouraged at this time. Coordinates: RA 11:38:26.80 Dec +03:22:07.0 Many thanks for your valuable observing efforts and observations! This AAVSO Special Notice was prepared by Elizabeth O. Waagen.

Posted on by Tammy Plotner

Weekend SkyWatcher’s Forecast: July 9-11, 2010

Greetings, Fellow SkyWatchers! Is it hot enough for you where you live? Not if you’re in the southern hemisphere… But this weekend the southern hemisphere is the place to be if you’re interested in catching a total solar eclipse! If you can’t travel that close, then let’s travel far, far away as we take a look at the season’s globular clusters… from easy to challenging! Be sure to keep an eye on Saturn and Mars as they draw closer together and look for bright Jupiter in the morning skies! Whenever you’re ready? Grab your optics and I’ll see you in the backyard…

July 9, 2010 – On this date in 1979, Voyager 2 quietly made its closest approach to Jupiter. How about if we take a close approach before dawn as well? Enjoy the waltz of the Galileans and all the fine details! If you enjoy watching the planets swim against the night sky, then be sure to keep an eye on the early evening visage of Saturn as Mars “back strokes” its way towards the Ring King!

Tonight let’s head on out toward two more close objects that appear differently from the rest (and each other)—same-field binocular pair M10 and M12. Located about half a fist-width west of Beta Ophiuchi, M12 (RA 16 47 14 Dec –01 56 52) is the northern most of this pair. Easily seen as two hazy round spots in binoculars, let’s go to the telescope to find out what makes M12 tick.


Since this large globular is much more loosely concentrated, smaller scopes will begin to resolve individual stars from this 24,000-light-year-distant Class IX cluster. Note that there is a slight concentration toward the core region, but for the most part the cluster appears fairly even. Large instruments will resolve out individual chains and knots of stars.

Now let’s drop about 3.5 degrees southeast and check out Class VII M10 (RA 16 57 08 Dec –04 05 57). What a difference in structure! Although they seem to be close together and similar in size, the pair is actually separated by some 2,000 light-years. M10 is a much more concentrated globular, showing a brighter core region to even the most modest of instruments. This compression of stars is what differentiates one type of globular cluster from another and is the basis of their classification. M10 appears brighter, not because of this compression but because it is about 2,000 light-years closer than M12.

July 10, 2010 – Today we celebrate the 1832 birth on this date of Alvan Graham Clark. An astronomer himself, Clark was also a member of a famous American family of telescope makers. He helped to create the largest refractor in the world—the lenses for the 40″ Yerkes Telescope. Perhaps the stress of worrying for their safety took its toll on Alvan, for he died shortly after their first use. Tonight let’s honor Clark’s work by studying a globular cluster suitable for all optics, M4. All you have to know is Antares!

Just slightly more than a degree west (RA 16 23 35 Dec –26 31 31), this major 5th magnitude Class IX globular cluster can even be spotted unaided from a dark location. In 1746 Philippe Loys de Cheseaux happened upon this 7,200-light-year-distant beauty, one of the nearest to us. It was also included in Lacaille’s catalog as object I.9 and in Messier’s in 1764. Much to Charles’s credit, he was the first to resolve it!


As one of the loosest, or most ‘‘open,’’ globular clusters, M4 would be tremendous if we were not looking at it through a heavy cloud of interstellar dust. To binoculars, it is easy to pick out a very round, diffuse patch, yet it will begin to resolve with even a small telescope. Large telescopes will also easily see a central ‘‘bar’’ of stellar concentration across M4’s core region, which was first noted by Herschel. As an object of scientific study, in 1987, the first millisecond pulsar was discovered within M4, which turned out to be ten times faster than the Crab Nebula pulsar. Photographed by the Hubble Space Telescope in 1995, M4 was found to contain white dwarf stars—the oldest in our galaxy—with a planet orbiting one of them! A little more than twice the size of Jupiter, this planet is believed to be as old as the cluster itself. At 13 billion years, it would be three times the age of the Solar System!

July 11, 2010 – Today marks the 1732 birth on this date of Joseph Jerome Le Francais de Lalande, who determined the Moon’s parallax and published a comprehensive star catalog in 1801. While we might not be determining the Moon’s parallax against the background stars, we’re certainly going to see its effects against the background Sun! Right now the southern hemisphere is the place to be if you’re interested in catching a total solar eclipse – but this eclipse isn’t going to be an easy one to observe unless you’re on the water.


Starting roughly 2000 kilometers northeast of New Zealand at 18:15 UT, totality will begin at local sunrise over the ocean. Minutes later the shadow pass will actually cross land as it encounters the island of Mangaia for about 3 minutes total time. Totality will brush by Tahiti, encompass the uninhabited atolls of the Tuamotu Archipelago and slide its way across the mysterious Easter Island. The Moon’s shadow will take once again to the water for another 3700 kilometers where it will reach its end at the very southernmost tip of South America. For those of you who have the great fortune to eclipse chase? We wish you the very best of skies and luck!

For hard-core observers, tonight’s globular cluster study will require at least a mid-aperture telescope, because we’re staying up a bit later to go for a same-low-power-field pair—NGC 6522 (RA 18 03 34 Dec –30 02 02) and NGC 6528 (RA 18 04 49 Dec –30 03 20). You will find them easily at low power just a breath northwest of Gamma Sagittarii, better known as Al Nasl, the tip of the ‘‘teapot’s’’ spout. Once located, switch to higher power to keep the light of Gamma out of the field, and let’s do some study.


The brighter, and slightly larger, of the pair to the northeast is Class VI NGC 6522. Note its level of concentration compared to the Class V NGC 6528. Both are located around 2,000 light years away from the galactic center and are seen through a very special area of the sky known as ‘‘Baade’s Window’’—one of the few areas toward our galaxy’s core region not obscured by dark dust.

Although each is similar in concentration, distance, etc., NGC 6522 has a slight amount of resolution toward its edges, while NGC 6528 appears more random. Although both NGC 6522 and NGC 6528 were discovered by Herschel on July 24, 1784, and both are the same distance from the galactic core, they are very different. NGC 6522 has an intermediate metallicity. At its core, the red giants have been depleted, or stripped tidally by evolving into blue stragglers. It is possible that core collapse has already occurred. NGC 6528, however, contains one of the highest metal contents of any known globular cluster collected in its bulging core!

Until next time? Keep reaching for the stars!

This week’s awesome images are: M10, M12, M4, NGC 6522 and NGC 6528 from Palomar Observatory, courtesy of Caltech. Alvan Clark historical image and eclipse information courtesy of NASA. We thank you so much!

Posted on by Tammy Plotner

Weekend SkyWatcher’s Forecast: July 2-4, 2010

Greetings, fellow SkyWatchers! Hopefully the rains have passed in your area and you’re ready for some dark skies and a double-dip… Double stars that is! This weekend we’ll take a look at some of the most colorful and interesting binary stars of the summer. Need more? Then hang tight as we take a look at one of the most concentrated globular clusters aroumd! Whenever you’re ready, I’ll see you in the backyard…

July 2, 2010 – This date marks the 1820 passing of British optician Peter Dollond, inventor of the triple achromatic lens. Dollond’s improvements to the refracting telescope included placing convex lenses of crown glass on either side of a biconcave flint glass lens to make the achromatic triplet lens we know today!

Now turn binoculars or telescopes toward magnitude 2.7 Alpha Librae, the second brightest star in the celestial ‘‘Scales.’’ Its proper name is Zuben El Genubi, and, as Star Wars as that sounds, the ‘‘Southern Claw’’ is actually quite close to home at a distance of only 65 light-years. No matter what size optics you are using, you’ll easily see Alpha’s widely spaced 5th magnitude companion, which shares the same proper motion. Alpha itself is a spectroscopic binary, as was verified during an occultation event, and its inseparable companion is only a half-magnitude dimmer according to the light curves. Enjoy this easy pair tonight!

July 3, 2010 – Tonight let’s go deep south and have look at an area that once held something almost half a bright as tonight’s later Moon and over four times brighter than Venus. Only one thing could light up the skies like that—a supernova.

According to historical records from Europe, China, Egypt, Arabia, and Japan, 1,003 years ago the very first supernova event was noted. Appearing in the constellation of Lupus, it was at first believed to be a comet by the Egyptians, yet the Arabs saw it as an illuminating ‘‘star.’’


Located less than a finger-width northeast of Beta Lupi (RA 15 02 48 Dec –41 54 42) and half a degree east of Kappa Centaurus, no visible trace is left of a once-grand event that spanned 5 months of observation, beginning in May and lasting until it dropped below the horizon in September 1006. It is believed that most of the star was converted to energy, and very little mass remains. In the area, a 17th magnitude star that shows a tiny gas ring and radio source 1459-41 remains our best candidate for pinpointing this incredible event.

Why you’re at it, try a challenging double star—Upsilon Librae (RA 15 37 01 Dec –28 08 06). This beautiful red star is right at the limit for a small telescope, but quite worthy, as the pair is a widely disparate double. Look for the 11.5-magnitude companion to the south in a very nice field of stars!

July 4. 2010 – Tonight let’s have a look at 400-lightyear-distant Rasalgethi—Alpha Herculis (RA 17 14 38 Dec +14 23 25). Known as the ‘‘Head of the Kneeling One,’’ it’s an easily resolved double and is noted for its fine color contrast. At magnitude 3.5, the variable bright primary is one of the largest known stars, with a diameter four times the Earth–Sun distance. Rasalgethi’s photospheric temperature is so low (3,000 Kelvin) that it barely glows a warm reddish orange. Meanwhile, its 5.4-magnitude companion is a yellow giant with a temperature twice the primary. The two together make Rasalgethi A seem a deeper red, while Rasalgethi B takes on a lovely yellow-green hue.

Need some fireworks? Then check out a single small globular—M80 (RA 16 17 02 Dec –22 58 30). Located about 4 degrees northwest of Antares (about two finger-widths), this little globular cluster is a powerpunch. Located in a region heavily obscured by dark dust, M80 will shine like an unresolvable star to small binoculars, but reveal itself to be one of the most heavily concentrated globulars in the telescope. Discovered within days of each other by Messier and Mechain, respectively, in 1781, this intense Class I globular cluster is around 36,000 light-years distant.


In 1860, M80 became the first globular cluster that was known to host a nova. As stunned scientists watched, a centrally located star brightened to magnitude 7 over a period of days, becoming known as T Scorpii. The event then dimmed more rapidly than expected, making observers wonder exactly what they had seen. Since most globular clusters’ stars are all about the same age, the hypothesis was put forward that perhaps they had witnessed an actual collision of stellar members. Given that the cluster contains more than a million stars, the probability is that some 2,700 collisions of this type may have occurred during M80’s lifetime.

Have a super weekend!

This week’s awesome images are: Zuben El Genubi, Field of SN1006, Upsilon Librae, Rasalgethi and M80. All done by Palomar Observatory, courtesy of Caltech. We thank you so much!