Posted on by Tammy Plotner

Aurora Alert!

Thanks to some very “hot” activity on the Sun, high latitude observers could be treated to some magnificent apparitions of the Aurora Borealis. But don’t count yourself out if you live a bit south of the pole… Sometimes the Northern Lights can surprise you!

According to Space Weather: “A magnetic filament exploded away from the sun on May 17th and propelled a cloud of plasma into space. The cloud (a CME) was not aimed directly at Earth, but it could deliver a glancing blow to our planet’s magnetic field during the late hours of May 19th.” And it wasn’t just then either… the Sun has been delivering some outstanding activity now for several days. Just check out this shot…

While the probability figures show as fairly low, don’t let that discourage you from looking. According to the latest information, the auroral oval is dipping low across the northern tier of the United States – leaving SkyWatchers from Canada through Kentucky an opportunity to spot a little skyglow. Why so optimistic? It’s the time of year…

Right now Earth’s magnetosphere and magnetopause (the point of contact) are positioned correctly to interact with the Sun’s influencing interplanetary magnetic field (IMF), and the plasma stream that flows past us as the solar wind. During the time around equinox – and even later – this leaves the door wide open for one of the most awesome signs of Spring… aurora! Visit the Geophysical Institute to sign up for aurora alerts, and use their tools to help locate the position of Earth’s auroral oval.

Spotting aurora isn’t hard, it simply just takes patience and reasonably dark skies. From experience you may see what looks like a distant search light – or it may appear as a red glow. At times the aurora can take on the appearance of a glowing green cloud that may or may not obscure the stars behind it. It shimmers and moves. How do you distinguish it from a cloud? Sometimes that can be difficult, but aurora will seem to “evaporate” rather than move with the wind. Having a few clouds won’t diminish the view and even moderate light pollution won’t stop it if the activity is strong enough. The most important factor is to give your eyes plenty of time to adjust to low light conditions and allow plenty of time for activity to happen.

Good luck… and may the Aurora be with you!

Many thanks to John Chumack of Galactic Images for sharing his recent solar photo and Aurora shots with us!

Posted on by Tammy Plotner

Weekend Observing Challenges – May 13-15, 2011

Greetings, fellow SkyWatchers!

I’m sure everyone has been enjoying following the morning planet show, but are you ready for something else? If you’ve got a telescope, then we’ve got some projects for you. While it’s definitely going to be a “moon light” weekend, that doesn’t mean that you can’t have fun! Let’s take a look at what the night has to offer…

On Friday and Saturday evening, the most prominent lunar feature will be the ancient and graceful Gassendi. Its bright ring stands on the north shore of Mare Humorum – an area about the size of the state of Arkansas. Around 113 km in diameter and 2012 meters deep, you will see a triple mountain peak in its center and the south wall eroded by lava flows. Gassendi offers a wealth of details to telescopic observers on its ridge and rille covered floor.

When you have finished with your lunar observations, let’s travel on to a fascinating double star. A little less than a handspan south of the last star in the handle of the “Big Dipper”, you will see a fairly bright star that is on the edge of unaided eye detection thanks to tonight’s gibbous Moon. Aim your telescopes or steady binoculars there for a real treat! Alpha Canum is more commonly known as Cor Caroli – or the “heart of Charles” – and is a true jewel easily split by the most modest of instruments. Although some observers may not be able to distinguish a color difference between the magnitude 2.8 and 5.6 companions, it has been my experience that most will see a faded blue primary (a magnetic spectrum variable) and pale orange secondary on this 120 light year distant pair. If you are equatorially aligned, turn off the drive and wait for 150 seconds. Widely separated Struve 1702 will be coming into view…

On Sunday night your lunar challenge will be a challenging one – worthy of the larger scope. Start by identifying past study craters, Hansteen and Billy. Due west of Hansteen you will find a small crater near the terminator known as Sirsalis. It will appear as a small, dark ellipse with a bright west wall with its twin, Sirsalis B on the edge. The feature you will be looking for is the Sirsalis Rille – the longest presently known. Stretching northeast of Sirsalis and extending for 459 kilometers south to the bright rays of Byrgius, this major “crack” in the lunar surface will show several branches – like a long dry river bed.

Tonight let’s go from one navigational extreme to another as viewers in the northern hemisphere try their hand at Polaris. As guide star for north, Polaris is also a wonderful double with an easily resolved, faint blue companion for the mid-sized telescope. But what about the south? Viewers in the southern hemisphere can never see Polaris – is there a matching star for the south? The answer is yes – Sigma Octantis – but at magnitude 5, it doesn’t make a very good unaided eye guide. Ancient navigators found better success with the constellation of Crux, better known as the “Southern Cross”. While Crux has many wonderful double stars, if southern hemispere viewers would like to see a star very similar to Polaris, then try your luck with Lambda Centauris. The magnitude difference between components and separation are about the same.

Good luck and clear skies!

Many thanks to Peter Lloyd for setting the Moon phase stage and Damien Peach for his incredible lunar photos!

Posted on by Tammy Plotner

Catch Seven Planets Now!

Planetary Alignment in Tasmania by Shevill Mathers

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No… What you’re looking at isn’t fireflies caught in the trees – but planets! Thanks to a little haze in Tasmania, incomparable sky shot artist, Shevill Mathers, was able to capture four planets lined up neatly before the dawn. One of the most beautiful facets of this image is that this is (with the exception of daily movement) how it appears to the unaided eye. Over the last couple of weeks, we’ve watched the inner planets gather along the ecliptic just before dawn… but even just a day makes a dramatic difference in their positions. We see it with our own eyes and we know it’s natural – but what makes it happen? Let’s find out…

Even though it’s been over 240 years since a very cool dude named Johannes Kepler was born, some of the laws he laid down about planetary motion still hold true today. Despite the fact he could have been jailed for supporting the Sun-centered Copernican theory, Kepler was teaching a class about the conjunction of Saturn and Jupiter when he realized that regular polygons bound one inscribed and one circumscribed circle at definite ratios, which, he reasoned, might be the geometrical basis of the Universe. From these conclusions, Kepler gave us three laws:

1. The orbit of every planet is an ellipse with the sun at one of the foci.

2. A line joining a planet and the sun sweeps out equal areas during equal intervals of time. (Suppose a planet takes one day to travel from point A to B. The lines from the Sun to A and B, together with the planet orbit, will define a (roughly triangular) area. This same amount of area will be formed every day regardless of where in its orbit the planet is. This means that the planet moves faster when it is closer to the Sun.) This is because the sun’s gravity accelerates the planet as it falls toward the Sun, and decelerates it on the way back out, but Kepler did not know that reason.

3. The squares of the orbital periods of planets are directly proportional to the cubes of the semi-major axis of the orbits. Thus, not only does the length of the orbit increase with distance, the orbital speed decreases, so that the increase of the orbital period is more than proportional.

May 10 Conjunction

Each day the second law is clearly demonstrated as the inner planets quickly change position because they are closer to the Sun. But what about the outer planets? They’re obeying the third law and will barely change positions over the next couple of months. Let’s take a look…

Location Map of Planets on May 10, 2011

Right now is the best time of year to catch all the planets in our solar system in the same night. After sunset, grab Saturn… before dawn you’ll find Uranus and Neptune hanging around in the constellation of Aquarius. As skies begin to brighten, you’ll find Mars, Jupiter, Venus and Mercury rising in progression just ahead of the Sun. What a wonderful way to celebrate the morning… by standing on Earth and checking out planetary motion!

Posted on by Tammy Plotner

The Early Morning Show – Eta Aquarid Meteor Showers While The Planets Align

Comet Halley Courtesy of Halley Multicolor Camera Team, Giotto Project, ESA

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Are you ready for the Eta Aquarid Meteor Shower? While the peak activity will be on the night of May 5/6, the offspring of Comet Halley are already beginning to make their appearance known. No matter where you live or what time zone you observe from, the best time to look for “shooting stars” is over the next week or so during the hours just before dawn.

Somewhere in the outer reaches of our solar system beyond the orbit of Jupiter, Comet Halley continues on its track – far away from its 1986 debris trail. However, now isn’t the only time we encounter this famous comet’s leftovers. Three times a year the Earth cruises through the dusty trail causing the Eta Aquarids, the Beta Aquarids (both in May) and the Orionids (during October). When a piece of this debris enters our atmosphere, it is traveling about 66 kilometers per second and can shine as brightly as the stars (3rd magnitude) in the constellation from which it appears to originate. Encountering a dense paticle stream may spark activity of up to 70 meteors per hour for lucky observers in the southern hemisphere, but don’t count yourself out if you live in the north! Because the constellation of Aquarius is relatively low for northern observers, this means we have at least a better chance of spotting those breathtaking Earth grazers!

Eta Aquarid Radiant Courtesy of NASA
Staring aound 4:00 a.m. (local time) the constellation of Aquarius is beginning to rise low to the southeast for the northern hemisphere and fall rates could be as marked as an average of one meteor every three or four minutes. Although meteors can appear from any point in the sky, your best northern skies bet will be to face generally southeast, gaze roughly halfway up the sky and get as comfortable as possible. A reclining lawn chair makes a wonderful meteor watching companion! Getting as far away as possible from city lights will also increase the amount of meteors you see – typically about 30 per hour for the northern hemisphere.

Don’t be discouraged if you’re clouded out or unable to view at the peak time. The most wonderful part about the Eta Aquarids is the fact the stream is very broad and activity is extended from April 21 until May 12. And there’s an added treat – the ongoing planetary alignment…

May 1 Visualization by Dave Reneke

Don’t let anyone discourage you from watching the Eta Aquarids if you have an opportunity. While it isn’t one of the most prolific showers of the year for the north, it is very well established and having dark skies will help tremendously. There is nothing finer than cradling a cup of hot coffee, sneaking a donut and waiting on the dawn while watching Kepler’s Laws of planetary motion in action. I am sure that you’ll come away feeling very happy indeed that you took the time to look for Comet Halley’s children racing by!

Posted on by Tammy Plotner

Weekend Observing Project: T Pyxidis

Are you ready to observe a nova event which can be caught in simple binoculars? Then open your eyes wide and locate T Pyxidis! Right now it’s showing up as just slightly fainter than magnitude 7, which means it is going to appear as an “extra star” in an otherwise rather starless portion of the constellation of Pyxis. Are you ready? Then let’s dance…

T Pyxidis is actually a binary star – one much like our own Sun with a white dwarf companion. Thanks to its diminuative, heavy-weight companion, matter from the primary star is always being drawn toward the secondary causing periodic thermonuclear explosions. Since there hasn’t been any real activity in about 45 years, astronomers believed T Pyx could possibly have began evolving into an entirely new system and activity wouldn’t occur perhaps for centuries. But they were wrong…

With a normal magnitude of 15.5, T Pyxidis would only be visible to some of the largest of amateur telescopes, but right now it can easily be spotted with average binoculars. The first finder chart seen on this page will get you in the right area and the one below will get you spot on (RA 09h 04m 41.50s Dec -32° 22′ 47.5″).

The fun part about observing T Pxidis is that it’s an object well suited for both hemispheres – one where the south is a bit more favored than the north – and all the “buzz” that goes with it. According to many sources, the white dwarf may be nearing its Chandrasekhar limit and become a Type 1a supernova when it collapses under its own weight. Says Edward Sion (et al); “The recurrent nova T Pyxidis has had 5 recorded thermonuclear explosions, more than any other recurrent nova, with an average time between nova outbursts of 19 years. However, it has been 44 years since its last nova outburst in 1966, making it long overdue for the next nova (supernova?). ”

However, don’t worry about this 3,300 light year distant stellar explosion happening any time soon. It’s estimated that kind of action may take as long as another couple of million years. “A key fact about T Pyx is that its accretion rate has been secularly declining since before the 1890 eruption, with the current rate being only 3% of its earlier rate. The decline in the observed accretion rate shows that the supersoft source is not self-sustaining, and we calculate that the accretion in T Pyx will effectively stop in upcoming decades.” say Bradley E. Schaefer (et al). “With this, T Pyx will enter a state of hibernation, lasting for an estimated 2,600,000 years, before gravitational radiation brings the system into contact again. Thus, T Pyx has an evolutionary cycle going from an ordinary CV state, to its current RN state, to a future hibernation state, and then repeating this cycle.”

But don’t you wait that long to observe it. For the next week or so, the Moon won’t interfere with your early evening chance to see this very cool cosmic customer!

Posted on by Tammy Plotner

Observing Challenge: A Gathering of Galaxies – Hickson 44

Hickson 44 by Warren Keller

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If you turn your telescope towards Leo, you just might discover a group of galaxies which reside close to our own Milky Way – Hickson Compact Group 44. At only 60 million light years away, this diverse and interesting collection has quite a story to tell!

Some three decades ago, Canadian astronomer, Paul Hickson set about the task of completing a list of 100 galaxies clusters. But, they couldn’t be just any set of galaxies – they had to be isolated, compact and within a limited magnitude range. His purpose was to study them for unusual redshifts among their members – and to improve our knowledge of galactic evolution. From his work came the theory that perhaps all well-known galaxies once emerged from such clusters and this hypothesis also contributed mightily to our understanding of dark matter as well. What Hickson left us with is a legacy of beautiful objects that challenge not only the telescope – but the mind as well.

In this photo done by Warren Keller, you will see from 11 o’clock: NGC 3193; 3190 and 3187 at center, and 3185 at 6 o’clock. A closer look reveals two tiny galaxies PGC (Principal Galaxies Catalog) 2806871 near 8 o’clock and PGC 86788 near 5 o’clock. As you can see, this group is an interesting collection of galaxy types – from barred spiral to elliptical in structure… close enough to share material as they gravitationally interact.

While some of you may recognize the three principle players in this galactic act as the “Leo Trio”, take a closer look at barred spiral NGC 3190. It was first discovered by Sir William Herschel in 1784 and was home to two supernova events in 2002. Lurking at its heart is an active galactic nucleus (AGN), home to a super-massive black hole. While the discovery of the rare Type Ia supernova was unusual enough, adding a second similar supernova event occurring simultaneously made this galactic action even more rare. Two young x-ray emitting events, set against a record breaking amount of obscuring dust!

Perhaps the interaction with nearby NGC 3187 is the root cause? It is, after all, evolving. Studies indicate an evolutionary sequence for Hickson compact groups in which the amount of diffuse light increases with the dynamical evolution of the group. “Compact groups are associations of a few galaxies in which the environment plays an important role in galaxy evolution.” says J. A. L. Aguerri (et al). “The low group velocity dispersion favors tidal interactions and mergers, which may bring stars from galaxies to the diffuse intragroup light. Numerical simulations of galaxy clusters in hierarchical cosmologies show that the amount of the diffuse light increases with the dynamical evolution of the cluster.”

While this group of galaxies is evolving and interacting together across vast distances, you can collect them all in the same eyepiece view found about halfway between Gamma and Zeta Leonis (RA: 10h18m00.4s Dec: +21°48’44”). They are by no means easy, the faintest of which is magnitude 13, but it can be accomplished with a minimum of a 150mm telescope under dark, clear skies.

Remember, the beauty is in the challenge… and the discovery!

Posted on by Tammy Plotner

Is Winking Near-Earth Asteroid GP59 Really the Missing Apollo 13 Panel?

Static Photo of GP59 Taken by Joe Brimacombe

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Is the recently discovered “winking” asteroid – GP59 – really the missing panel from the ill-fated Apollo 13 mission? According to the latest internet buzz, it could be as possible as Mars being as large as the full Moon…

With the recent anniversary of the Apollo 13 disaster conveniently coinciding with the discovery of “winking” near-Earth asteroid GP59, anxious theorists are ready to believe they are one and the same. Thanks to the asteroid’s rapid tumble and quick magnitude changes, it’s no small wonder that it would appear on the surface to be so. Just take a look at this GP59 Video done by Joe Brimacombe and you’ll see why.

With discoveries of artifacts continually found on Earth, such as missing pieces of the Titanic, it wouldn’t take a great leap of faith to believe we might have recovered one in space as well – even the panel that blew away from Apollo 13. However, we need to take a look at that equation times four – the 4 panels that protected the LM during launch – the Spacecraft Lunar Module Adapter (SLA) panels. Says Marshall Eubanks, ” In the Saturn V launches, the SLA panels were ejected, with separation velocity of about 2 meters / second. They were 6.4 meters tall, about 3 meters wide at the apex, made of a 0.043 meters thick aluminum honeycomb, plus about 1 mm of cork and paint, and so have a very low mass-area ratio. If 2011 GP59 is an SLA panel, then it should have 3 clones with very similar orbits.”

With today’s huge advances in amateur telescopes, there remains a possiblity – however small – that we may someday recover objects like these. “I could see a situation in which a panel was spinning around its short axis, with that axis tilted a bit toward the Sun, so that there would be a systematic pressure accelerating or decelerating it. (Sort of like what the fans of spin-stabilized solar sails hope to do.) The problem would be that over a full orbit around the Sun, the net acceleration would cancel out.” says Bill Gray. “The bottom line remains: there is no particularly good reason to think there’s a connection between these panels and 2011 GP59. (Even if the panels were big enough to match the observed brightness of 2011 GP59, which they aren’t.) If the panels are ever recovered, they’re apt to be in much more Earth-like orbits. With 36 of them out there, the odds seem decent that we’ll see one of them someday.”

But don’t hold your breath when it comes to GP59… it is what it is… a tumbling, oblong asteroid roughly 47 meters in diameter. “Usually, when we see an asteroid strobe on and off like that, it means that the body is elongated and we are viewing it broadside along its long axis first, and then on its narrow end as it rotates ,” said Don Yeomans, manager of NASA’s Near-Earth Object Program Office at the Jet Propulsion Laboratory in Pasadena, Calif. “GP59 is approximately 50 meters [240 feet] long, and we think its period of rotation is about seven-and-a-half minutes. This makes the object’s brightness change every four minutes or so.”

And our hearts skip a beat just thinking of the possiblities…

Posted on by Tammy Plotner

Lingering Lyrids…

Meteor FireBall Break-up Courtesy of John Chumack

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Although we couldn’t remind you just before the date of the Lyrid meteor shower peak, there’s no reason to believe the show is over just yet! If you’re an early riser, this just might be your chance to catch a lingering Lyrid…

Every year the Earth encounters the dusty remnants of the tail of Comet Thatcher (C/1861 G1). It doesn’t occur on a very specific date, but we do know it happens in late April. While the peak time is dawn on April 23, it’s not uncommon to see between 5-20 meteors per hour through the 26th.

Why such a widely varied date and diversified fall rate? The answer is… thanks to Jupiter’s massive gravity, we never know exactly when we might encounter a “clump” of comet debris. The majority of the time, the spawn of Comet Thatcher is no bigger than a grain of sand, traveling through our atmosphere at 49 km/s (110,000 mph). Incredibly enough, these fast moving particles can light up as brightly as 2nd magnitude – easily seen from moderately light polluted skies. Some have even been known to appear as fireballs and leave smoke-like trails that linger in the sky for several minutes!

For the past 2600 years, mankind has been observing the Lyrids – and you can, too. Since their radiant is near the bright star, Vega, your best time to observe is in the hours just before dawn. For many observers, the constellation of Lyra will be high to the east around 4:30 a.m. local time and nearly overhead just before dawn. Even southern hemisphere observers with an unobstructed northern horizon can enjoy the show, too. While there will be some Moon to contend with, placing it behind an obstruction like the corner of a building or a tree will help reduce the glare.

Clouded out or decided to sleep until it was light? Don’t forget your lessons on how to “listen” with your radio! According to NASA, “This year many amateur radio operators tuned into the Lyrids using a technique called radio forward scattering. When fast-moving meteoroids strike Earth’s atmosphere they heat and ionize the air in their path. The luminous ionized trails are not only visually striking — they also reflect radio waves. During a major meteor shower, radio signals from TV stations, RADAR facilities, and AM/FM transmitters are constantly bouncing off short lived meteor trails. For those who know how to listen, it’s easy to hear the echoes.” Don’t remember how to listen? Then take the radio meteor listening tutorial courtesy of the North American Meteor Network.

Will you catch a lingering Lyrid? You never know until you try…

Many thanks to John Chumack of Galactic Images and to NASA for the illustrations.

Posted on by Tammy Plotner

Sun Day, April 17th – Get Out And Enjoy!

In keeping with global astronomy month, it’s time to get out and enjoy another favorite astronomical target – the Sun! It’s a star that can be seen from both hemispheres and a great way to involve your friends, neighbors and family in the pleasure of observing. What’s more… there’s activity going on right now, too!

If you’re lucky enough to have an h-alpha filtered telescope, it’s a great time to set up your equipment and catch a host of solar prominences, flares and plague activity. Just check out this image below taken by John Chumack and done with a Lunt 60mm/50F H-Alpha dedicated solar telescope and B1200 blocking filter.

These images were taken recently, and to make the current solar action even easier to see, John colorized the next in blue!

Don’t have h-alpha? No problem. The white light view is awesome! On the west limb is exiting sunspot 1186 and hot on its heels is the more compact and darker 1190. At center stage is prominent 1191 and to its northeast is 1193.

If you don’t have either an h-alpha solar scope, or a proper white light solar filter, you can still observe the Sun with simple equipment! Got binoculars or a small refractor telescope? Then you’ve got the basis for a great projection set up! Safely cover one side of your binoculars or telescope’s finderscope and aim towards the Sun by aligning the shadow. Project the light onto a surface such as a paper plate or piece of cardboard and adjust the focus until you see a clear circle of light and focus the sunspots. The projection method is used by several famous solar telescopes, including Mt. Wilson Solar Observatory! Always remember… never look into the optics while aimed at the Sun and that your optics will get hot during use.

No telescope or binoculars? Then let’s keep trying… this time the pinhole camera method! Get two pieces of cardboard – one will need to be white or have white paper attached to it for the screen. Cut a small square in the other piece of cardboard, and tape aluminum foil over the square. Now make a pinhole in the middle of the foil. This is your “projector”. With the Sun behind you, hold the pinhole projector as far away from the screen as you can and see if you can catch some dark patches on your projected circle that indicate sunspots!

For a lot of other great projects and ideas on how you can celebrate Sun Day, be sure to visit Astronomers Without Borders Sun Day pages. Now, get on out there and enjoy Sun Day!

H-Alpha images are courtesy of John Chumack of Galactic Images, the white light solar images is courtesy of SDO/HMI and many thanks to Astrononomers Without Borders for the Sun Day logo!

Posted on by Tammy Plotner

Global Lunar Week – April 10 to 16, 2011

Lunar Week Logo Courtesy of Astronomers Without Borders

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In 2009, hundreds of thousands of people participated in one way or another with the International Year of Astronomy, and there’s no reason to let the excitement die! Astronomers Without Borders are celebrating the entire month of April as Global Astronomy Month and one of the focus points is just three days from arrival… Global Lunar Week!

” A week-long series of programs, from April 10 through 16, will be dedicated to the Moon during Global Astronomy Month to help people rediscover our closest companion in space.” says AWB. “Lunar Week takes place while the Moon is well-placed for observation in the evening sky. As the Moon’s phases and positions change during its orbit around the Earth, there will be Moon-themed star parties to observe the Moon by telescope and naked eye, educational programs, online observing events, competitions and a celebration of the Moon in different cultures.”

Astronomers Without Borders has a theme – One People * One Sky. For all of those who read Universe Today, we realize quickly how astonomy can bring together friends from different countries, different cultures and different time zones. Wouldn’t it be wonderful if we could all observe together?

The dream can come true…

Sander Klieverik from AstronomyLive is working with telescopes around the world to celebrate Global Lunar Week and bring the view right to you.

“The week will start with an amazing broadcast from the historic Chamberlin observatory of the Denver university (with the help of Prof. R. Stencel). It will start april 9th between 7-10pm local time (Denver), which is 01-04 GMT April 10th.” says Sander. “Our goal is to get as many telescopes pointed towards the Moon as possible. I hope that there will be a continuous view of the Moon somewhere from the globe the whole week.”

How can you participate? It’s easy! Just tune into the AstronomyLive Website and follow the instructions. “During the Lunar Week, AstronomyLive will host at least two broadcasts, currently scheduled 15th and 16th of April.” instructs Klieverik. “The first broadcast will take you on a journey across the 85% illuminated lunar surface, on the hunt for the most beautiful craters during this phase, the ´Crater hunt´. The craters at the terminator will receive special attention, the dark side of the moon that changes during the Moon phase. Please know that you will see a LIVE view of the Moon and not some Moon photo. The same accounts for the “Apollo Hop”.

Come one, come all… Lunatics are welcome!