What's Up This Month - December 2010 From Facebook Group

If it seems like you haven’t seen a lunar eclipse for a while, you’re right. It’s been about three years since seen a total lunar eclipse from anywhere on Earth. But the dry spell ends this month with an eclipse on the night December 20-21.
Northern skies are much darker this time of year as the sun moves further below the horizon than during the summer months. And all stargazers, north and south, enjoy the return of the bright stars of December in the constellations Orion, Canis Major, Auriga, and Taurus.

So go find your mittens and bundle up. Here’s what to look for this month…

Geminid Meteor Shower

The Geminids is usually one of the year’s best meteor showers… reliable, steady, and getting better over the past decades. The radiant of the shower is in Gemini near the bright stars Castor and Pollux. The meteors will appear to trace their path back to the radiant, but they can appear anywhere in the sky. And they will be visible from the northern and southern hemisphere.

The Geminids are expected to peak on December 14 at 1100 GMT, which coincides with darkness in the Americas and Western Pacific. But wherever you live, if the skies are clear, you’ll see meteors. After midnight local time is usually best. The Moon is near first quarter during the peak, so it won’t wash out the skies too much.
As with all meteor showers, you need only a place to view open dark sky, warm clothing, and a way to comfortably gaze at the sky for long periods. No optics required.

The source of the Geminids is the strange object 3200 Phaethon, which is probably an extinct comet.

Lunar Eclipse

Finally… a lunar eclipse! Visible completely in North America, the first total eclipse since 2008 will occur on December 20-21. Mid-eclipse is set for 8:17 UT. That’s after midnight in most parts of North America. So stock up on sleep the night before!
You can observe the eclipse without optics, but binoculars or a low-power telescope will give you a better view of the copper-colored Moon during the total phase of the eclipse. It will be a beautiful sight… don’t miss it!

Note: The Moon will rise at sunset during the total phase of the eclipse for observers in eastern Australia and all of New Zealand. So it will still make for good viewing at dusk.

The Planets

Mercury is low in the southwest, about 6 degrees above the horizon after sunset during the first 10 days of December. It’s bright, but hard to see without binoculars.

Venus is a staggering sight in the southeastern early morning sky. It’s at magnitude -4.9 in early December, as bright as it ever gets. Some say it’s bright enough to cast a shadow on a Moonless night. You might even be able to follow it after sunrise in the daytime sky.

While outshone by Venus, Jupiter continues to dominate the evening sky all month. It presents much detail in a small telescope, and is always worth a careful look. Don’t forget to look for the Great Red Spot.

Moon Phases

New Moon: Dec. 5 at 17:36 Universal Time (UT)
First Quarter: Dec. 13 13:59 (UT)
Full Moon: Dec. 21 08:13 17:27 (UT)
Last Quarter: Dec. 28 04:18 (UT)

How To See The Great Red Spot

First sight of the Great Red Spot is a high point for any amateur astronomer.  Few tire of the sight of this massive and ancient storm in Jupiter’s upper atmosphere.  But while it looks fine in photos, it’s surprisingly hard to see in a small telescope.  Here are three tips to increase your chances of seeing the “GRS”, and a few words about this swirling vortex that’s large enough to swallow several Earths.


Tip 1 – Make sure the GRS is visible.  The spot rotates, more or less, as Jupiter rotates.  So every 10 hours the spot makes a full rotation around the visible disk of the planet.  You’ll get your best chance of seeing the Red Spot as it crosses the central meridian… the imaginary north-south line that bisects the planet’s disk.  Even if the GRS is an hour before or past the meridian, you can get a good view.

So when the the Great Red Spot cross the meridian?  Your best bet to get this information is to go to Sky and Telescope’s transit table here…

This page lists all transit times over the next few months.  Times are listed in Universal Time (or Greenwich Mean Time).  You can determine UT relative to your local time with this website…

http://wwp.greenwichmeantime.com/

So for example, the Sky and Telescope table shows transit of the GRS on December 1 at 8:17 and 18:13, and on December 2 at 4:08 and 14:04 UT.  In my timezone (Eastern Standard), this means there are transits at 3:17 a.m. and 1:13 p.m. and 11:08 p.m. on December 1, and 9:04 a.m. on December 2.  Of course, I’ll only see the GRS when the sky is dark, so the transits at 3:17 a.m. and 11:08 p.m. are my best bets.

Tip 2 – Make sure you have steady sky.   The GRS appears quite small, even at 150-200x.  So you need good steady sky to see it.  If the stars are twinkling madly, or if you see the limb of the planet rippling, the seeing is poor and your chance of seeing the spot is reduced.  Steady sky in which the stars barely twinkle is nearly essential.  And you can try a light-green color filter (a #56 or #58) on your eyepiece to make the spot appear darker against the planet’s disk.

Tip 3 – Try hard!  Don’t just take a quick peak and give up.  If takes effort to see fine detail in a telescope.  Look carefully, rest your eyes, and look again.  It takes time for the detail to register in your brain.  And you may need to wait for brief moments of steady seeing.

It’s worth a try to see the Great Red Spot.  This massive storm, which packs winds of more than 400 km/h, may have been first seen nearly 350 years ago, and may be much older.  The storm is just south of Jupiter’s equator, and rotates counter-clockwise as seen from Earth.  It measures about 30,000 km across at its long point, and half as much at its shorter axis, though the spot has become less elongated in the past 15 years.  No one knows why.  Nor is anyone sure what causes its red color.  It may be a colorful brew of complex organic molecules in the planet’s upper atmosphere.

Courtesy: OMA

Story of the Century? NASA May Announce Thursday to Have Found Life on Saturn's Moon Titan

NASA has called a 2 p.m. news conference for Thursday "to discuss an astrobiology finding that will impact the search for evidence of extraterrestrial life." The group includes Pamela Conrad, author of a paper on geology and life on Mars; and James Elser, an Arizona State University professor involved in a NASA-funded program that emphasizes looking at the chemistry of environments where life evolves (and not just looking at water or carbon or oxygen); Felisa Wolfe-Simon (an oceanographer) has written extensively on photosynthesis using arsenic recently (she worked on the team mentioned in this article); Steven Benner (a biologist) is on the "Titan Team" at the Jet Propulsion Laboratory; they're looking at Titan (Saturn's largest moon) as an early-Earth-like chemical environment. This is likely related to the Cassini mission.

The space agency did not release more details, but the list of news conference participants is telling, according to blogger Jason Kottke.

"So, if I had to guess at what NASA is going to reveal on Thursday, I'd say that they've discovered arsenic on Titan and maybe even detected chemical evidence of bacteria utilizing it for photosynthesis (by following the elements)," Kottke wrote.

We'll find out in short order...

What's Up This Month - May 2010 from Facebook Group

May brings the fringe benefits of stargazing. Rich smells of new leaves and lush green grass. Warmer nights, unburdened by winter’s frost or summer’s insects and humidity. And the slow build of birdsong that greets early-morning stargazers who steal a preview of the summer stars, or perhaps a glimpse of Jupiter as it rises before the sun in the eastern sky.

For northern-hemisphere observers, bright stars are few this month. But you can easily spot a few prominent constellations. Ursa Major (which includes the Big Dipper) is almost overhead about 9 p.m. Follow the arc of the Dipper’s handle to the bright yellow star Arcturus and then on to white Spica in the constellation Virgo. And the sickle-shape of Leo and Coma Berenices serve as signposts to the galaxies visible in larger telescope as the Earth’s sky points out of the plane of our galaxy into the rest of the universe.

For southern-hemisphere observers, the coolness of autumn is offset by an embarrassment of celestial riches. The Milky Way lies directly overhead along with the sky’s four brightest stars: Sirius, Canopus, Rigil Kent, and Arcturus. Even a casual sweep of the Milky Way’s arc reveals the star clusters and nebulae of the constellations Centaurus, Crux, Carina, and Vela.


Deep-Sky Highlights

The previous discussion posts this month by our gem member Patrick, defines almost everything special for every deep-sky junkie... and that too in his own unique perspective and in much efficient way... yet just to complete our monthly What's Up This Month post... heres a small preview again...

From both hemispheres, even a casual observer will enjoy the delights of the constellation Corvus, the Crow. Lying just north of Hydra, the Serpent, Corvus is easily distinguished by its quadrilateral shape of stars riding on the serpent’s back.
Greek legend recounts how Corvus was sent with a cup by Apollo to fetch water from a running spring. The crow complied, but stopped too long by a fig tree to gorge himself on the sweet fruit. Apollo was not amused. He confronted the crow, who falsely blamed the serpent Hydra for delaying his mission. But Apollo cast the crow and the serpent into the sky along with the cup, which we now know as the constellation Crater.

The dedicated stargazer will find dozens of galaxies in this part of the sky. But even small telescopes reveal M104, the Sombrero Galaxy, just over the Corvus-Virgo border. The beautiful spiral galaxy looks like a fuzzy oval in a small telescope. An 6-inch or larger scope reveals the central dust lane. And the Hubble Telescope reveals a breathtaking disk of stars and dust and an unusually bright galactic core.

Once you spot M104, try to find the striking asterism called “Jaws”, just half a degree west. This group of stars looks much like a celestial shark intent on dining on the great galaxy. The brightest stars of the asterism form its mouth, while the fainter stars form a long northward arc of the shark’s body. You can see both galaxy and Jaws in a low-power field of view with a telescope.

Southern observers can see omega Centauri, the sky’s brightest globular cluster, high in the sky. But May is the best month for observers at mid-to-low-northern latitudes to spot the cluster. If you’re south of 42 degrees north latitude, look for the cluster just above the southern horizon near midnight. It will look like a dim fuzzy ball made slightly orange-red by the atmospheric dust towards the horizon.

The Moon

Last Quarter: May 6, 5:15 UT
New Moon: May 14, 2:05 UT
First Quarter: May 21, 0:43 UT
Full Moon: May 28, 0:07 UT

The Planets

Mercury. Early last month, Mercury was as nearly as high in the sky as it ever gets. And it was uncommonly easy to find, right next to brighter Venus in the western sky at sunset. But the show’s over. The speedy planet has swung behind the sun and barely peaks above the horizon a half-hour before sunrise late in May. Diligent observers with binoculars might glimpse the planet during the last few days of the month.

Venus. The slower-moving Venus shines at a stunning magnitude -3.9 in the west-northwest sky at sunset for most of May. It’s brighter than anything else in the sky except the Sun and Moon. The planet cruises through the Hyades star cluster, the group of stars which marks the V-shaped head of the constellation Taurus. The double-star tau Tauri is just 1/2 degree west of Venus on May 4th. And on May 15th, as the crescent Moon sets, the planet passes between the stars that mark the tip of the bull’s horns.

Mars. Glowing dimly in the south at sunset, Mars is still receding from Earth and presents a tiny disk in a backyard telescope. Even the northern polar cap will be all but invisible, as summer begins in the planet’s northern hemisphere on May 12th.

Jupiter. The big planet rises in the constellation Pisces just before the sun in the east-southeast early this month. But by the end of May, it’s up by 3 a.m. The planet will put on a good show in June and July as it gets higher in the sky during peak observing hours.

Saturn. The good news? Saturn lies high in the sky right now, above the murk of the horizon and easy to find between the bright stars Regulus and Spica. The bad news? Saturn is almost as dim as it ever gets… about magnitude +1.0. The rings are just 1.7 degrees from edge-on right now and look like tiny spikes protruding from the planet. Over the next 15 years, the rings will slowly increase their inclination as seen from Earth. Even binoculars will show Saturn’s big moon Titan off to one side. You can track Titan’s motion from night to night.

Uranus is just 1 degree from Jupiter by month’s end, and will play cat and mouse with the bigger planet all summer when both are better positioned for telescopic viewing.

Neptune also rises at dawn at the border of Capricorn and Aquarius. As with Jupiter and Uranus, the planet is better seen in July and August.

Celestial Events

The eta Aquarids meteor shower peaks around May 6 as the Earth passes through the trail of Halley’s Comet. Not a particularly fine shower, it’s best seen from low northern to mid-southern latitudes before dawn.

For casual stargazers, the fading stars of winter along with the Moon and Venus put on a lovely display at sunset on May 15.

Dazzling Venus appears just above the lovely star cluster M35 at sunset on May 21. You’ll need binoculars or a telescope at low magnification to see the pair together.
The full Moon appears south to south-west of the bright star Antares on the night of May 27.

Happy Stargazzing

Messier’s “Lost” Star Cluster

Like many constellations this time of year, Hydra contains mostly galaxies. The venerable Burnham’s Celestial Handbook lists some 60 galaxies in this long constellation. But most are dim… less than magnitude 12 and quite hard to see with scope smaller than 10″. And since Hydra sports few bright stars, many casual observers pass by Hydra in search of better sights.

Which is unfortunate. Because there are a few memorable bright deep-sky objects nestled in the great sky serpent. One of the prettiest is the oft-overlooked open star cluster M48. This cluster, along with M44 and M67 in Cancer just 10 degrees north, make for a pleasant short observing session on an April weekend with binoculars or a small scope.

To find Messier 48, look about 10 degrees southwest of Hydra’s head, and 10 degrees southeast of the bright star Procyon. (Remember that 10 degrees is about the width of your fist held at arms length). About 8 degrees southwest of the head, look for the 4th magnitude star C Hydrae; M48 is 2.5 degrees southwest of this star. It should fit in the same field of view of binoculars or your finderscope. You may even see the cluster with the unaided eye if your sky is clear and dark. At magnitude 5.8, it’s just on the edge of visibility as a large fuzzy patch about the size of the full moon.

In a telescope at 40-50x, M48 is a pleasing sight . You’ll see 80-100 stars of 8-12th magnitude spread over a full degree of sky in a distinctly wedge-shaped pattern, with a dark keyhole-shaped notch at the base of the wedge. The brightest star, at the southeast edge, appears yellow-white. A detailed analysis of the star colors and brightness suggests the cluster is some 300 million years old. M48 lies some 2,000 light years away.

Charles Messier observed M48 in 1771, and noted the position in his catalog. But later astronomers could find no cluster at the coordinates Messier recorded. Did the star cluster disappear? Likely not. As it turns out, Caroline Herschel recorded a star cluster, now known as NGC2548, about 5 degrees south of Messier’s position for M48. Astronomy historians agree that Messier observed NGC2548 and simply erred when determining its position.

And yet…

Astronomy writer Steven James O’Meara writes in his excellent book The Messier Objects, that when observing M48, he noticed with his unaided eye a fuzzy patch about 5 degrees southeast of M48… the location originally recorded by Messier. He casually mistook this patch for M48, but when he observed it with his telescope, it was not visible. With binoculars slightly de-focused, the patch look fuzzy and cluster-like, though he determined it’s really just a group of unassociated stars. To the unaided eye, this mystery patch was actually brighter than M48 according to the sharp-eyed O’Meara.

Is this patch what Messier saw and recorded as M48?

Try to see this little patch for yourself as you look for M48 this weekend.

The “Ghost of Jupiter”

A little further along the constellation Hydra, you’ll find a dying sun gently blowing its outer layers into interstellar space. The great William Herschel, who discovered this nebula known as NGC 3242, noted its resemblance in size and shape to the planet Jupiter. But if you look at it carefully, you’ll find it takes on many other shapes and patterns, including that of a logo well known to American TV viewers…

Like many such nebulae, NGC 3242 looks in passing like the disk of a planet. Upon his discovery of this nebula in 1785, Herschel wrote, “Beautiful, brilliant, planetary disk ill defined, but uniformly bright, the light of the colour Jupiter… 1′ in diameter”.

A century later, the diligent amateur Admiral William Smyth wrote, “From its size, equable light, and colour, this fine object resembles Jupiter.”

But it may have been Robert Burnham who first referred to this nebula as the “Ghost of Jupiter”. Though to many, the greenish hue of the nebula, caused by raving-hot oxygen atoms set aglow by the dying star, makes the nebula look more like Uranus than Jupiter. See for yourself… it’s a lovely sight and well worth close inspection on a warm April night.

The “Ghost of Jupiter” deserves at least as much attention as the more famous Ring Nebula in the constellation Lyra. Like the Ring Nebula, NGC 3242 is also a planetary nebula, the last hurrah of a star that’s run out of fuel and approaches the end of its life as a white dwarf.

But at a relatively bright magnitude 7.3, NGC 3242 is at least 2 magnitudes brighter than the Ring Nebula, and not much harder to find. Look for it about 2 degrees southwest of the star μ (mu) Hydrae.

NGC 3242 is plenty bright enough to see in 7×50 binoculars. In a telescope, it appears star-like at below 30x, but starts to take on shape and color at 100x and above. Use as much magnification as your telescope and sky allows. And try a UHC or OIII filter to bring out the contrast, especially if you live in the city.

Good sky and high magnification bring out the sublime features of this object. The oval outer shell defines the overall shape. But look closer. Inside the outer shell, you may see a curved, slightly closed inner shell, making NGC 3242 look a little like an eye. Or some say, like the logo for CBS (the Columbia Broadcasting System in the U.S.). Which is why you sometimes hear it called “The CBS Nebula”.

The nebula lies about 1,600 light years away, and spans 0.5 light years. The central star of the nebula shines at a dim magnitude 12.5. Its central core glows at 90,000 Kelvin; it will soon settle down as a slowly-cooling white dwarf.

What's Up This Month - March 2010

March is a “change over” month for the night sky. The bright stars of the northern winter move westward and give way to the star-sparse nights of March, April, and May. That’s because we’re starting to look out of the plane of the Milky Way and into intergalactic space. So we see fewer stars and nebulae and open star clusters, but more galaxies become visible, especially those of the Virgo cluster and smaller collections like the M81 and Leo groups.

And of course, the seasons change this month. The southern hemisphere begins fall and the northern hemisphere begins spring on March 20 at 17:32 UT. At this time, the sun sits at the point where the celestial equator and ecliptic meet. All points on the Earth receive an equal amount of sunlight, hence the term “equinox”, or “equal nights”.

For deep sky sights, try the two Messier objects in Cancer, M44 and M67. Both are old open clusters. The better-known M44 is more spread out and brighter, but M67 is fun to examine because its shape conjures many analogies. Some say M67 looks like a fountain of stars. Others suggest a “Pac-man” shape.

And if you’re keen to see a nice galaxy, check out NGC 2903, just off the nose of Leo. This lovely 9th magnitude spiral is one of the best in this part of the sky. It was just missed by Messier; William Herschel discovered this galaxy in 1784. It lies 21 million light years away.

As for planets, Mars lingers in western Cancer, not far from M44 and M67. It’s fading this month, but a good telescope, high magnification, and steady sky will reveal a few surface features.
And Saturn is set to take center stage for planet lovers. The planet reaches opposition on March 21 and will reach its brightest over the next few months.

Moon

Last Quarter: March 7, 15:42 UT
New Moon: March 15, 22:01 UT
First Quarter: March 23, 11:00 UT
Full Moon: March 30, 2:25 UT

Planets

Mercury lies a generous 10 degrees above the western horizon after just after sunset. It reaches magnitude -0.9 by month’s end and sits just below the brighter Venus.

Venus is still close to the sun in the western sky, but it rises higher this month to get 10-12 degrees above the horizon by March 31. It’s not much to see through a telescope since it’s near full phase. But it makes a lovely pairing with Mercury later this month, and with the Moon on March 16-17.

Mars lingers in the sky, as mentioned above. At its closest in January, the disk of Mars was 14 arc-seconds across. It will shrink to 9 arc-seconds by month’s end.

Jupiter is lost in the glare of the sun this month.

Saturn gears up for a good show over the spring and early summer. The ringed planet hovers in Virgo between the stars Spica and Denebola. The planet is directly opposite the sun on March 21, and rises high enough for viewing by mid-evening. The rings are still just 4 degrees from edge-on. A small telescope at 75x or more will clearly show the rings. Saturn this month is about 1.27 billion km away from Earth.

Uranus is too close to the sun to be observed this month.

Neptune. Just above the horizon at dawn. Wait for a month or two to try to spot this icy giant planet.

Celestial Events

The March equinox occurs at 17:32 UT, bringing spring and autumn to the northern and southern hemispheres.

And don’t forget to check out the zodiacal light early this month. Look for a tall pyramid of whitish-yellow light just after sunset. Dark sky is required.

Happy Stargazing


Courtesy : OMA