Get Great Astronomy Apps and Support Astronomers Without Borders

Screenshot for Android, telescope control for SkySafari3. Courtesy AWB

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Celebrate the last two weeks of Global Astronomy Month and get a great price on the very popular SkySafari 3 apps for Apple and Android mobile devices and Mac OS X. Not only will you get an app that has been called a ‘game-changer’ for astronomy software, but during a special promotion, 30% of proceeds from all SkySafari sales will be donated to Astronomers Without Borders to support their wonderful programs.

All three versions of SkySafari 3 — Basic, Plus and Pro – are now at significant discounts, and if you’ve been considering purchasing SkySafari, now is the time, especially since you can support the great work of Astronomers Without Borders at the same time.

SkySafari 3 – $1.99 (regularly $2.99). 120,000 stars and 220 star clusters, nebulae, and galaxies. Solar system’s major planets and moons using NASA spacecraft imagery, 20 asteroids and comets.

SkySafari 3 Plus – $11.99 (regularly $14.99). Wired or wireless telescope control with accessories sold separately. 2.5 million stars, 31,000 deep sky objects (with entire NGC/IC catalog), over 4,000 asteroids, comets, and satellites.

SkySafari 3 Pro – $39.99 (regularly $59.99). Wired or wireless telescope control with accessories sold separately. 15 million stars (most of any astronomy app), 740,000 galaxies to 18th magnitude, over 550,000 solar system objects including every known comet and asteroid.

If you don’t need the SkySafari app, please consider donating to AWB.

Mike Simmons, who leads AWB, told Universe Today that this astronomy outreach organization really could use financial help.

“We do probably a half-million dollars in programs each year based on the hard work of passionate amateur astronomers and educators around the world,” he said, all on way less than $25,000 a year.

“This can’t be sustained, of course, and our programs — and everyone’s expectations of us — continue to grow,” Simmons wrote. “This is really, really important to us. 2012 presents many opportunities and we’re working on them. But we need to convert some of the passion we have in abundance to income to keep it going. If we can’t do it this year then I’m not sure we can do it in the future.”

Another way to help AWB is to purchase special eclipse glasses for the upcoming eclipse and the Venus transit – for which AWB has big plans for helping people around the world observe this very infrequent event.

Also, there is the a program allowing people to buy a quality small refractor and have a second one donated to a club or school in a developing country.

For more information, check out Astronomers Without Borders and the SkySafari 3 app sale, the eclipse glasses and the BOGO for a small refractor telescope for you and a needy school.

Thanks in advance for your support of a great organization!

Dust Shells Seen for the First Time Around Dying Stars

The Helix Nebula
The Helix Nebula - the fate of most stars including our Sun. These new results illuminate how nebulae like this are formed. Credit: NASA, NOAO, ESA, the Hubble Helix Nebula Team, M. Meixner (STScI), and T.A. Rector (NRAO).

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Stars get pretty sloppy towards the end of their lives.  As the nuclear fuels start to wane, the star pulsates – expanding and contracting like a marathon runner catching her breath.  With each pulsation, the dying star belches out globs of gas into space that eventually get recycled into a new generation of stars and planets.  But accounting for all that lost material is difficult.  Like trying to see a wisp of smoke next to a stadium spotlight, observing these tenuous sheets of stellar material swirling just over the surface of the star is considerably challenging.  However, using an innovative technique to image starlight scattering off interstellar grains, astronomers have finally succeeded in seeing ripples of dust flowing off dying stars!

The stars – W Hydra, R Doradus, and R Leonis – are all highly variable red giants, stars that are no longer fusing hydrogen in their cores but have moved on to forming heavier elements.  Each is completely enveloped by a very thin dust shell most likely made up of minerals like forsterite and enstatite.  These grains can only form once the raw ingredients have flowed some distance from the star.  At distances roughly equal to the size of the star itself, the gas has cooled enough to allow atoms to start sticking together and forming more complex compounds.  Minerals like these will go on to seed asteroids and possibly rocky planets like the Earth in the continual cycle of death and rebirth playing out in the Galaxy.

The paper describing this discovery, accepted to the journal Nature, can be found here.

The astronomers who recently reported this discovery used the eight meter wide Very Large Telescope in the Chilean Atacama Desert – and a suite of clever tools – to tease out the subtle reflections off these dust shells.  The trick to seeing light bouncing off interstellar dust particles involves taking advantage of one of light’s wave properties.  Imagine you had a length of rope: one end is in your hand, the other tied to a wall.  You start to wiggle your end and waves travel down the cord.  If you move your arm up and down, the waves are perpendicular to the floor; if you move your arm from side to side, they are parallel to it.  The orientation of those waves is known as their “polarization”.  If you mixed things up by constantly changing the direction in which your arm was oscillating, the orientation of the waves would be similarly confused.  The rope would bounce in all directions.  With out a preferred direction of movement, the rope waves are said to be “unpolarized”.

Light waves emitted from the surface of star are just like your chaotic rope flinging. The oscillations in the electric and magnetic fields that make up the propagating light wave have no preferred direction of motion – they are unpolarized.  However, when light bounces off a dust grain, all that confusion drops away.  The waves now oscillate in roughly the same direction, just as if you decided to only bounce the rope up and down.  Astronomers call this light “polarized”.

A polarizing filter only allows light with a specific orientation to pass through.  Hold it one way, and only “vertically polarized” light – light where the electric field is oscillating up and down – will pass. Turn the filter ninety degrees, and you’ll only transmit “horizontally polarized” light.  If you have polarizing sunglasses, you can try this yourself by rotating the glasses and watching how the the scene through the lenses gets brighter and darker.  This is also a nice demonstration of how our atmosphere polarizes incoming sunlight.

A shell of dust around a star will polarize the light that bounces off it.  Just like the sky gets brighter and dimmer as you turn your sunglasses, looking at a such star through differently oriented polarizing filters will reveal a halo of polarized light surrounding it.  The different orientations will reveal different segments of the halo.  By combining polarimetric observations with interferometry – the beating together of light waves from widely separated spots on a telescope mirror to create very high-resolution images – a thin ring of scattered light reveals itself around these three stars.

These new observations represent a milestone in our understanding of not only a star’s end game but also the production of interstellar dust that follows. Like the smokestacks of great factories, red giant stars expel a soot of minerals into space, carried aloft by stellar winds.  With meticulous observation, results such as these can help tie together the death of one generation of stars with the birth of another.  Unraveling the mysteries of grain formation in space takes us one step closer to piecing together the many steps that lead from stellar death to the creation of rocky planets like our own.

Shuttle Discovery Mated to 747 Carrier for her Final Flight to Smithsonian Home

At the Shuttle Landing Facility at NASA’s Kennedy Space Center in Florida, mating of space shuttle Discovery and the Shuttle Carrier Aircraft is complete in the mate-demate device nn April 15, 2012. Credit: NASA/Kim Shiflett

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Following a busy weekend of work, Space Shuttle Discovery is now attached piggyback style to the Shuttle Carrier Aircraft (SCA) at NASA’s Kennedy Space Center and all set for the final flight to her ultimate resting place at the Smithsonian National Air and Space Museum’s Steven F. Udvar-Hazy Center in Virginia on Tuesday April 17. There she will reside on permanent display for the public just a short distance outside Washington D.C.

In the predawn hours on Saturday (April 14), Discovery was towed for the last time to the Mate- Demate Device (MDD) at the Shuttle Landing Facility and NASA’s specially outfitted Boeing 747 Jumbo Jet awaiting her in Florida. But howling winds in the subsequent hours delayed the hoist and mate on the back of the huge carrier plane.

Today (Sunday, April 15), the winds calmed and technicians raised Discovery and mechanically bolted her atop the SCA jet, designated NASA 905.

“It may have taken two days because of weather, but Discovery was attached to the Shuttle Carrier Aircraft today (April 15),” NASA KSC spokesman Allard Beutel told Universe Today after the mating operation was finished.

“And we’re on track to give Discovery a proper send off to its new home on Tuesday morning.”

NASA 905 will carry out all the remaining flights to ferry Space Shuttles Discovery, Enterprise and Endeavour to their permanent museum sites in Virginia, New York and California. The last remaining shuttle – Atlantis – will be towed later this year to her new home a few miles down the road at the Kennedy Space Center Visitor Complex.

Towing Discovery into the mate/demate device at the Shuttle Landing Facility at the Kennedy Space Center in Florida. Credit: NASA/Kim Shiflett

The initial mating of Discovery and the SCA in the mate/demate device was completed at about 11:15 a.m. EDT. The shuttle was finally secured to the carrier jet a few hours later on Sunday afternoon and will be backed out of the MDD on Monday, April 16.

NASA 905 will lift off at about 7 a.m. to ferry Discovery to the Washington Dulles International Airport in Virginia on April 17 with a planned arrival between 10 to 11 a.m. depending on weather.

If you spot the shuttle along the way, send Ken your photos to post here at Universe Today.

The SCA will fly over multiple locations from Washington, DC to the Udvar-Hazy Center as low as 1500 feet for the public to enjoy before finally landing at Dulles Airport.

Ken hopes to be on hand at the Udvar-Hazy Center for Universe Today

Discovery’s final departure from the Kennedy Space Center marks a bittersweet time for all who worked on the shuttle program as well as fans and advocates of space exploration across the globe.

New Evidence For Fomalhaut Planets

Fomalhaut's exoplanet (NASA, ESA, P. Kalas (UC, Berkeley))

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The planetary system of the star Fomalhaut has been one of intense debate over the past few years. In 2008, it was announced that a large, Saturn mass planet shepherd a large dust ring and was spotted in visual images from Hubble. But in late 2011 infrared observations called the previous detections into question. Now joining the discussion is the recently completed Atacama Large Millimeter/sub-millimeter Array (ALMA). This radio observatory suggests that there may be more planets than previously detected.

ALMA sits in the high Atacama desert in northern Chile. This dry location is ideal for linking together the 66 radio dishes (although only 15 were used in the new observations) to give unprecedented resolution. With this new set of eyes, astronomers from the University of Florida and Bryant Space Science Center were able to study the fine details in the dust ring. These details were then compared to various models of how rings should function in different conditions.

The dust ring has several characteristics that any explanation would have to reproduce. The first was that the ring is slightly oval shaped. It must be exceptionally thin and have a sharp cutoff both on the interior and exterior edges. If the previously claimed planet, Fomalhaut b, were the only one present, it could not account for the outer edge of the disk being sharply truncated as well as the inner edge. Another possibility is that the ring is simply newly formed as the result of a collision between two planets and has not yet had time to dissipate giving it the sharp appearance. However, the authors note that planets at such a distance from the parent star shouldn’t have high enough relative velocities to crush them so finely.

Since neither of these explanations are sufficient, the team proposes that there are two planets that shepherd the ring: One interior and one exterior to it. Within our own solar system, we see similar effects in Uranus’ ε ring which is constrained by the moons Cordelia and Ophelia. Similarly, Saturn’s F ring is shepherded by Prometheus and Pandora. By varying the mass of hypothetical planets in the models, the authors could create a ring similar to that seen around Fomalhaut. However, the best fit was created by a pair of planets that were less than three times the mass of the Earth which would mean that the proposed mass for Fomalhaut b was significantly too high, further casting doubt on its existence. Additionally, the proposed orbit of Fomalhaut bwas 10 AU off from the orbit of the hypothetical interior shepherd planet.

Ultimately, these two planets are only hypothetical. Detecting them in a more direct fashion will prove challenging. The fact that their orbits wouldn’t be very close to line of sight as well as their distance from the star would make radial velocity detection impossible. Given the low proposed mass and the distance, they would reflect too little light to be able to be directly observed with current telescopes.

Weekly SkyWatcher’s Forecast – April 16-22, 2012

Messier 83 - Credit: Bill Schoening/NOAO/AURA/NSF

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Greetings, fellow SkyWatchers! It’s International Dark Skies Week and a great time to enjoy astronomy! We’ll start off with an impressive galaxy for even small optics and enjoy two meteor showers. There are planets and planetary nebula to explore, as well as some awesome globular clusters. If you’re in the mood, there’s some history to learn and plenty of astronomy facts! Whenever you’re ready, meet me in the back yard…

Monday, April 16 – Before binocular observers begin to feel that we have deserted them, let’s drop in on a binocular and very small telescope galaxy that resides roughly a handspan below Spica – M83 (Right Ascension: 13 : 37.0 – Declination: -29 : 52). Starhop instructions are not easy for this one, but look for a pair of twin stars just west of the easily recognized “box” of Corvus – Gamma and R Hydrae. You’ll find it about four fingerwidths further south of R.

As one of the brightest galaxies around, the “Southern Pinwheel” was discovered by Lacaille in 1752. Roughly 10 million light-years distant, M83 has been home to a large number of supernova events – one of which was even detected by an amateur observer. To binoculars it will appear as a fairly large, soft, round glow with a bright core set in a delightful stellar field. As aperture increases, so do details – revealing three well defined spiral arms, a dense nucleus and knots of stars. It is truly a beauty and will become an observing favorite!

Tuesday, April 17 – Today in 1976, the joint German and NASA probe Helios 2 came closer to the Sun than any other spacecraft so far. One of its most important contributions helped us to understand the nature of gamma ray bursts.

Are you ready for even more meteors? Tonight is the peak of the Sigma Leonids. The radiant is located at the Leo/Virgo border, but has migrated to Virgo in recent years. Thanks to Jupiter’s gravity, this shower may eventually become part of the Virginid Complex as well. The fall rate is very low at around one to two per hour. While you’re watching this region of sky, be sure to check out the close pairing of Saturn and Spica!

With tonight’s dark skies, this would be a perfect time for larger telescopes to discover an unusual galaxy grouping in Hydra about 5 degrees due west of the Xi pairing (RA 10 36 35.72 Dec -27 31 03.2).

Centralmost are two fairly easy ellipticals, NGC 3309 and NGC 3311, accompanied by spiral NGC 3322. Far fainter are other group members, such as NGC 3316 and NGC 3314 to the east of the 7th magnitude star and NGC 3305 north of the 5th magnitude star. While such galaxy clusters are not for everyone, studying those very faint fuzzies is a rewarding experience for those with large aperture telescopes.

Wednesday, April 18 – Before we have any Moon to contend with, let’s head out in search of an object that is one royal navigation pain for the northern hemisphere, but makes up for it in beauty. Start with the southernmost star in Crater – Beta. If you have difficulty identifying it, it’s the brightest star east of the Corvus rectangle. Now hop a little more than a fistwidth southeast to reddish Alpha Antilae. Less than a fistwidth below, you will see a dim 6th magnitude star that may require binoculars in the high north. Another binocular field further southwest and about 4 degrees northwest of Q Velorum is our object – NGC 3132 (RA 10 07 01.76 – Dec -40 26 11.1). If you still have no luck, try waiting until Regulus has reached your meridian and head 52 degrees south.

More commonly known as the “Southern Ring” or the “Eight Burst Planetary,” this gem is brighter than the northern “Ring” (M57) and definitely shows more details. It can be captured in even small instruments, larger ones will reveal a series of overlapping shells, giving this unusual nebula its name.

Thursday, April 19 – Today in 1971, the world’s first space station was launched – the Soviet research vessel Salyut 1. Six weeks later, Soyuz 11 and its crew of three docked with the station, but a mechanism failed denying them entry. The crew carried out their experiments, but were sadly lost when their re-entry module separated from the return spacecraft and depressurized. Although the initial phase of Salyut 1 seemed doomed, the mission continued to enjoy success through the early 1980s and paved the way for Mir.

Tonight let’s try picking up a globular cluster in Hydra that is located about 3 fingerwidths southeast of Beta Corvus and just a breath northeast of double star A8612 – M68 (Right Ascension: 12 : 39.5 – Declination: -26 : 45).

This class X globular was discovered in 1780 by Charles Messier and first resolved into individual stars by William Herschel in 1786. At a distance of approximately 33,000 light-years, it contains at least 2000 stars, including 250 giants and 42 variables. It will show as a faint, round glow in binoculars, and small telescopes will perceive individual members. Large telescopes will fully resolve this small globular to the core!

Friday, April 20 – By 1850, Lord Rosse had used the 72 inch speculum-mirrored “Leviathon at Parsontown” (Birr Castle, Ireland) to catalogue fourteen previously indecipherable glowing clouds in deep space as “spiral nebulae.” The very first one resolved was originally a discovery of Charles Messier – found while chasing a comet on the night of October 13, 1773. That discovery, M51, had to wait 72 years until large reflecting telescopes unveiled its spiral form. It would take another 75 years before M51’s extragalactic nature became an indisputable fact. Interestingly, observers have now become so accustomed to seeing spiral structure in brighter galaxies that even mid-sized scopes can see M51 (Right Ascension: 13 : 29.9 – Declination: +47 : 12) – the Whirlpool Galaxy – as a “Grand Spiral.” Tonight see what Rosse saw for yourself.

Start in Ursa Major by locating Mizar (Zeta) and Alkaid (Eta), then rotate the line between these two 90 degrees south using Eta as the pivot. With the line oriented to the southwest, cut it in half. With good conditions and a mid-sized scope, you can be initiated into the mystery of the spiral nebulae – nebulae whose individual stars had to await the development of very large professional scopes and long-exposure photography to reveal their stellar nature to the questing human imagination!

Saturday, April 21 – It’s Saturday night and we’ve got New Moon! Tonight, let’s use our binoculars and telescopes and take a look at a spectacular stellar sphere. Let’s find one of the best northern hemisphere globular clusters – M3! You can locate M3 (Right Ascension: 13 : 42.2 – Declination: +28 : 23) easily by identifying Cor Caroli (Alpha Canes Venatici) and Arcturus. Sweep your binoculars along a line halfway between the two and you will uncover this condensed beauty just east of Beta Comae. With added inches and magnification, the stars are out to play!

Discovered by Charles Messier on May 3, 1764, this condensed ball of approximately a half million stars is one of the oldest formations in our galaxy. At 35-40,000 light years distant, this awesome globular cluster spans 220 light years and is believed to be 10 billion years old.

Now let’s check out a dandy little group of stars that are about a fistwidth southeast of Procyon and just slightly more than a fingerwidth northeast of M48. Called C Hydrae, this group isn’t truly gravitationally bound, but is a real pleasure to large binoculars and telescopes of all sizes. While they share similar spectral types, this mixed magnitude collection will be sure to delight you!

Sunday, April 22 – Today celebrates the birthday of Sir Harold Jeffreys, who was born in 1891. Jeffreys was an astrogeophysicist and the first person to envision Earth’s fluid core. He also helped in our understanding of tidal friction, general planetary structure, and the origins of our solar system.

Start your moonless morning off before dawn with a chance to view the peak of the Lyrid meteor shower. Since the radiant is near Vega, you will improve your chances of spotting them when the constellation of Lyra is as high as possible. This stream’s parent is Comet Thatcher, and it produces around 15 bright, long-lasting meteors per hour!

Before you begin your observations tonight, be sure to check out the cool triangulation of Theta Leonis, Regulus and Mars!

Let’s begin tonight in eastern Hydra and pick up another combination Messier/Herschel object. You’ll find M48 (Right Ascension: 8 : 13.8 – Declination: -05 : 48) easily just a little less than a handspan southeast of Procyon.

Often called a “missing Messier,” Charles discovered this one in 1711, but cataloged its position incorrectly. Even the smallest of binoculars will enjoy this rich galactic cluster filled with more than 50 members including some yellow giants. Look for a slight triangle shape with a conspicuous chain of stars across its center. Larger telescopes should use lowest power since this will fill the field of view and resolve splendidly. Be sure to mark your notes for both a Messier object and Herschel catalog H VI 22!

Until next week? Dreams really do come true when you keep on reaching for the stars!

See Big and Bright Saturn at Opposition This Weekend

Saturn on April 3, 2012 with the moons Dione (Top-Left) and Tethys (Bot.-Right) as the ringed planet approaches opposition.Credit: Efrain Morales.

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Now is the time to take a look at the planet Saturn, as the ringed planet will be at opposition this weekend, making its closest approach to Earth on April 15, 2012. Its face will be fully illuminated by the Sun, so get out those telescopes, binoculars and your imaging equipment! We want to see your photos! Efrain Morales from the Jaicoa Observatory took this image of Saturn and some of its moons on April 3.

The giant planet’s rings are now optimally angled at over 13 degrees, revealing them better than they have appeared in the past five years. To see the rings of Saturn during opposition, in the northern hemisphere point your telescopes east to southeast at nightfall and south around midnight. For reference, Saturn will be near the bright star Spica, in the constellation Virgo. In the southern hemisphere, Saturn will be above the eastern horizon at 10pm local time, still near Spica.

If the skies aren’t clear in your area, the Slooh Space Observatory will broadcast a free, real-time feed of Saturn at opposition. Their coverage will begin on Sunday, April 15th, starting at 6:30 p.m. PDT/9:30 p.m. EDT/01:30 UTC (April 16th). Slooh will provide two distinct observatory feeds — one from a remote location in South Africa and the second from their world-class observatory site in Canary Islands off the coast of Africa. The broadcast can be accessed at Slooh’s homepage or by visiting Slooh’s Google+ page, where you will be able to see a panel of experts interact live via G+ Hangouts On Air.

The experts include Duncan Copp, producer of many astronomical documentaries, including “In the Shadow of the Moon”; Amanda Hendrix, Cassini’s deputy project scientist from NASA’s Jet Propulsion Laboratory; and Bob Berman, author of numerous astronomy books and contributing editor and monthly columnist for Astronomy Magazine.

“In 40 years of observing the heavens and watching people’s reactions to celestial glories, I’ve found that no object elicits more amazement and sheer wonder than Saturn. I am thrilled to be part of Slooh’s live close-up visit to that magnificent planet,” said Bob Berman.

Send us your images of Saturn by joining our Flickr group, or send us your images by email (this means you’re giving us permission to post them). Please explain when and where you took it, the equipment you used, etc.

The Heavens are Ablaze With Blazars

his image taken by NASA's Wide-field Infrared Survey Explorer (WISE) shows a blazar -- a voracious supermassive black hole inside a galaxy with a jet that happens to be pointed right toward Earth. These objects are rare and hard to find, but astronomers have discovered that they can use the WISE all-sky infrared images to uncover new ones. Image credit: NASA/JPL-Caltech/Kavli

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From a JPL press release:

Astronomers are actively hunting a class of supermassive black holes throughout the universe called blazars thanks to data collected by NASA’s Wide-field Infrared Survey Explorer (WISE). The mission has revealed more than 200 blazars and has the potential to find thousands more.

Blazars are among the most energetic objects in the universe. They consist of supermassive black holes actively “feeding,” or pulling matter onto them, at the cores of giant galaxies. As the matter is dragged toward the supermassive hole, some of the energy is released in the form of jets traveling at nearly the speed of light. Blazars are unique because their jets are pointed directly at us.

“Blazars are extremely rare because it’s not too often that a supermassive black hole’s jet happens to point towards Earth,” said Francesco Massaro of the Kavli Institute for Particle Astrophysics and Cosmology near Palo Alto, Calif., and principal investigator of the research, published in a series of papers in the Astrophysical Journal. “We came up with a crazy idea to use WISE’s infrared observations, which are typically associated with lower-energy phenomena, to spot high-energy blazars, and it worked better than we hoped.”

The findings ultimately will help researchers understand the extreme physics behind super-fast jets and the evolution of supermassive black holes in the early universe.

WISE surveyed the entire celestial sky in infrared light in 2010, creating a catalog of hundreds of millions of objects of all types. Its first batch of data was released to the larger astronomy community in April 2011 and the full-sky data were released last month.

This artist's concept shows a "feeding," or active, supermassive black hole with a jet streaming outward at nearly the speed of light. Such active black holes are often found at the hearts of elliptical galaxies. Not all black holes have jets, but when they do, the jets can be pointed in any direction. If a jet happens to shine at Earth, the object is called a blazar. Image credit: NASA/JPL-Caltech

Massaro and his team used the first batch of data, covering more than one-half the sky, to test their idea that WISE could identify blazars. Astronomers often use infrared data to look for the weak heat signatures of cooler objects. Blazars are not cool; they are scorching hot and glow with the highest-energy type of light, called gamma rays. However, they also give off a specific infrared signature when particles in their jets are accelerated to almost the speed of light.

One of the reasons the team wants to find new blazars is to help identify mysterious spots in the sky sizzling with high-energy gamma rays, many of which are suspected to be blazars. NASA’s Fermi mission has identified hundreds of these spots, but other telescopes are needed to narrow in on the source of the gamma rays.

Sifting through the early WISE catalog, the astronomers looked for the infrared signatures of blazars at the locations of more than 300 gamma-ray sources that remain mysterious. The researchers were able to show that a little more than half of the sources are most likely blazars.

“This is a significant step toward unveiling the mystery of the many bright gamma-ray sources that are still of unknown origin,” said Raffaele D’Abrusco, a co-author of the papers from Harvard Smithsonian Center for Astrophysics in Cambridge, Mass. “WISE’s infrared vision is actually helping us understand what’s happening in the gamma-ray sky.”

The team also used WISE images to identify more than 50 additional blazar candidates and observed more than 1,000 previously discovered blazars. According to Massaro, the new technique, when applied directly to WISE’s full-sky catalog, has the potential to uncover thousands more.

“We had no idea when we were building WISE that it would turn out to yield a blazar gold mine,” said Peter Eisenhardt, WISE project scientist at NASA’s Jet Propulsion Laboratory in Pasadena, Calif., who is not associated with the new studies. “That’s the beauty of an all-sky survey. You can explore the nature of just about any phenomenon in the universe.”

Great ISS Sightings – All Nights this Week of April 9

ISS crossing the evening sky at about 8:40 PM EDT on April 8, 2012 in New Jersey; 25 sec exposure, about 30 degree elevation, looking south. Credit: Ken Kremer.
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    Calling all Skywatching and Space Fans ! This is a great week for observing the International Space Station (ISS), swiftly crossing the evening nighttime sky.

    All this week from Monday thru Saturday, folks all across vast portions of the United States and Canada will be treated to fabulous viewings of the International Space Station. And at very convenient viewing times in the early evening, after dinner and in prime time.

    From Maine to Vancouver, from Ohio to Texas, from Florida to New Mexico – many of you will be in for a rather pleasurable ISS treat.

    Of course the exact viewing times, days, elevations, durations and directions varies greatly depending on your exact location – and clear skies. And the viewing parameters change daily.

    Check out this NASA website for Human Spaceflight Sighting Opportunities. It’s simple. Just plug in your country, state and select a local town. Also check out – Heavens Above.

    This evening, Monday April 9, I shot a few 20 to 30 second exposures as the ISS was speeding past at about a 30 degree elevation. But the best viewings at far higher elevations are yet to come the remainder of this week.

    ISS speeds across evening sky on April 9, 2012. 6 Humans from the US, Russia and the Netherlands are currently living aboard the ISS. Credit: Ken Kremer

    The International Space Station is the brightest manmade object in the night sky and even brighter than Venus depending on orbital mechanics. Only our Sun is brighter. Since Venus is an evening observing target this week, maybe you’ll even be lucky to see the ISS seem to pass close by that hellishly hot planet.

    Have you ever looked at the ISS hurtling overhead ?

    Take some shots and send them to Ken to post here at Universe Today.

    And remember, 6 Humans from the US, Russia and the Netherlands are currently residing aboard the ISS, conducting science research and sending back gorgeous shots of all of us back here on Earth.

Weekly SkyWatcher’s Forecast: April 9-15, 2012

M95 - Credit: NOAO/AURA/NSF

[/caption]Greetings, fellow SkyWatchers! It’s shaping up to be a great week to enjoy astronomy. For both hemispheres, the Virginid Meteor shower is underway and its peak occurs late Monday night / early Tuesday morning. Need more celestial fireworks? Then keep looking up as the “April Fireballs” will be visiting, with their peak beginning about a week from today and lasting for 24 days. Even if you only catch one of these bright travelers as they sparkle across the starry sky, it will make your night! But hang on, there will be plenty to explore. Bright stars and bright planets are featured – as well as some of the season’s best galaxies. Keep your telescope out and don’t get spooked, because the “Ghost of Jupiter” will be a challenge object! If you want to know more about astonomy history, and what you can see with just your eyes and your optics, then meet me in the back yard…

Monday, April 9 – Tonight let’s take a journey towards the 25th brightest star in the night sky – 1.3 magnitude, Alpha Leonis. Regulus, known as “The Little King,” is the brightest star in Leo. At 77 light-years away, this star is considered a “dwarf” despite shining with a visible light almost 150 times that of Sol. The orange-red giant Arcturus and the blue white “dwarf” Regulus both share a common absolute magnitude very close to 0. The reason the two stars shine with a similar intrinsic brightness – despite widely different physical sizes – is Regulus’ photosphere is more than twice as hot (12,000 C) as Arcturus. While observing Regulus, look for a distant companion of magnitude 8.5. Normally low powers would best concentrate the companion’s light, but try a variety of magnifications to help improve contrast. For those with large aperture scopes, look for a 13.1 magnitude “companion’s companion” a little more than 2 arc seconds away!

Tuesday, April 10 – Be sure to get up before dawn to enjoy the Virginid meteor shower. The radiant point will be near Gamma in the bowl of Virgo. The fall rate of 20 per hour is above average for meteor showers, and with the Moon partially out of the equation this morning, you’re in for a treat!

Tonight, let’s have a look at Arcturus – a star whose distance from the Earth (10 parsecs) and radial velocity (less than 200 meters per second) can almost be considered a benchmark. By skydark you will see 0.2 magnitude, Arcturus – the brightest star in Bootes and 4th brightest star in the night sky – some 30 degrees above the eastern horizon. Apparent to the eye is Arcturus’ orange color. Because a star’s intrinsic luminosity relates to its apparent brightness and distance, Arcturus’ absolute magnitude is almost precisely the same as its apparent magnitude. Just because Arcturus’ radial velocity is nearly zero doesn’t mean it isn’t on the move relative to our Sun. Arcturus is now almost as close as it will ever get and its large proper motion – perpendicular to our line of sight – exceeds 125 kilometers per second. Every 100 years Arcturus moves almost 1 degree across the sky!

Since you’ve looked at a red star, why not look at a red planet before you call it a night? Mars is still making a wonderful apparition. Have you noticed it dimming even more? Right now it should be about magnitude -0.5. You may have noticed something else about Mars in the eyepiece, too… It’s getting smaller!

Wednesday, April 11 – Today is the birthday of William Wallace Campbell. Born in 1862, Campbell went on to become the leader of stellar motion and radial velocity studies. He was the director of Lick Observatory from 1901 to 1930, and also served as president of the University of California and the National Academy of Sciences. Also born on this day – but in 1901 – was Donald H. Menzel – assistant astronomer at Lick Observatory. Menzel became Director of Harvard Observatory, an expert on the Sun’s coronosphere and held a genuine belief in the extraterrestrial nature of UFOs. Today in 1960, the first radio search for extraterrestrial civilizations was started by Frank Drake (Project Ozma). In 1986, Halley’s Comet closed within 65 million kilometers of the Earth – as close as it would get.

Tonight, why don’t we honor Campbell’s work as we try taking a look at a variable ourselves? RT (star 48) Aurigae is a bright cephid that is located roughly halfway between Epsilon Geminorum and Theta Aurigae. This perfect example of a pulsating star follows a precise timetable of 3.728 days and fluxes by close to one magnitude.

Thursday, April 12 – Today in 1961, Yuri Gagarin made one full orbit of the Earth aboard Vostok 1, while also becoming the first human in space. Also today (in 1981) Columbia became the first Space Shuttle to launch.

Break out the telescope tonight and launch your way towards Iota Cancri – a fine wide disparate double of magnitudes 4.0 and 6.6 separated by some 30 arc seconds. This true binary is so distant from one another that they take over 60,000 years to complete a single orbit around their common center of gravity! Located slightly less than a fist’s width due north of M44, this pair is about 300 light years distant. Both stars shine with a light considerably brighter than our Sun and observers may note a subtle gold and pale blue color contrast between them.

Friday, April 13 – With no early evening Moon to contend with, this is a fine opportunity to have a look at a group of galaxies between Leo’s paws. Start at Regulus and look due east toward Iota Leonis. Halfway between the two (less than a fist from Regulus) and two finger-widths northeast of Rho Leonis, you’ll encounter Messier Galaxies M95 (Right Ascension: 10 : 44.0 – Declination: +11 : 42) and M96 (Right Ascension: 10 : 46.8 – Declination: +11 : 49) – both within the same low power field of view. At magnitude 9.2, the brighter – and slightly rounder – M96 lies northeast of 9.7 magnitude, M95. Pierre Mechain discovered both galaxies on March 20, 1781 and Messier added them to his catalog 4 days later. These two galaxies are two of the brightest members of the Leo I galaxy group located some 38 million light-years away.

To see another Messier member of the Leo I group, center on M96 and shift the galaxy south. From the north side of the low power field, the 9.3 magnitude galaxy M105 (Right Ascension: 10 : 47.8 – Declination: +12 : 35), nearby 10th magnitude NGC 3384 (Right Ascension: 10 : 48.3 – Declination: +12 : 38), and 12th magnitude NGC 3389 (Right Ascension: 10 : 48.5 – Declination: +12 : 32) will come into view. M105 was discovered by Mechain on the night Messier catalogued M95 and 96 but was not formally added to Messier’s catalog. Based on Mechain’s observing notes, Helen Sawyer Hogg added it to Messier’s list in 1947 – along with galaxy M106 and globular cluster M107. Mechain failed to notice M105’s bright neighboring galaxy – NGC 3384. NGC 3384 is actually slightly brighter than the faintest Messier discovered – M91.

We’re not done yet! If you center on M105 and shift due north less than a degree and a half you will encounter 10th magnitude NGC 3377 (Right Ascension: 10 : 47.7 – Declination: +13 : 59) – a small elongated galaxy with a stellar core. There are a dozen galaxies visible to moderate amateur instruments (through magnitude 12) in the Leo I region of the sky!

Saturday, April 14 – Today is the birthday of Christian Huygens. Born in 1629, the Dutch scientist went on to become one of the leaders in his field during the 17th century. Among his achievements were promoting the wave theory of light, patenting the pendulum clock, and improving the optics of telescopes by inventing a new type eyepiece and reducing false color through increasing the focal length of refractor telescopes. Huygens was the first to discover Saturn’s rings and largest satellite – Titan. Of the rings, Huygens said, “Saturn: encircled by a ring, thin and flat, nowhere touching, and inclined to the ecliptic.”

Wanna’ check Saturn out? It will be rising in the constellation of Virgo not long after the sky begins to turn dark. If you’re not sure of which “star” it is, just wait for awhile and you’ll find it about a fistwidth northwest of bright, blue/white Spica. Be sure to check out the ring system! Right now they have a very nice southern tilt which will allow you a great view of the shadow of the planet on the rings – and the shadow of the rings on the planet. If the atmosphere will allow, power up! Something you may never have thought of looking for could be happening… Can you see the planet’s edge through the Cassini division? Be sure to look for wide orbiting Titan and some of Saturn’s smaller moons slipping around the ring edges.

Tonight our challenge is also planetary – but it’s the planetary nebula – the “Ghost of Jupiter”. Begin by identifying the constellation of Hydra. Starting at Alpha Hydrae, head east about a fist’s width to find Lambda within a field of nearby fainter stars. Continue less than a fist southeast and locate Mu. You’ll find the “Ghost of Jupiter” (NGC 3242) lurking in the dark less than a finger-width due south. At magnitude 9, the NGC 3242 (Right Ascension: 10 : 24.8 – Declination: -18 : 38) gives a strikingly blue-green appearance in even small scopes – despite being more than 1500 light years away.

Sunday, April 15 – Tonight keep a watch for the “April Fireballs.” This unusual name has been given to what may be a branch of the complex Virginid stream which began earlier in the week. The absolute radiant of the stream is unclear, but most of its long tails will point back toward southeastern skies. These bright bolides can possibly arrive in a flurry – depending on how much Jupiter’s gravity has perturbed the meteoroid stream. Even if you only see one tonight, keep a watch in the days ahead. The time for “April Fireballs” lasts for two weeks. Just seeing one of these brilliant streaks will put a smile on your face!

And if you can’t take your eyes off Leo, then there’s good reason. The combination of Theta Leonis, Regulus and Mars certainly calls attention to itself!

While we’re out, let’s journey this evening towards another lovely multiple system as we explore Beta Monocerotis. Located about a fist width northwest of Sirius, Beta is one of the finest true triple systems for the small telescope. At low power, the 450 light year distant white primary will show the blue B and C stars to the southeast. If skies are stable, up the magnification to split the E/W oriented pair. All three stars are within a magnitude of each other and make Beta one of the finest sights for late winter skies.

If you hadn’t noticed, Saturn is at opposition tonight, meaning it will be viewable from dusk until dawn. Be sure to check out the “Ring King” – but wait until it has risen well above the lower atmosphere disturbance for a superior view!

Until next week, I wish you clear and steady skies!

Timelapse: A Tribute to Sky Gazers

If you’ve fallen for the enchantment of a night out watching the stars, you’ll relate to and revere in this new timelapse video.

“This timelapse production is a tribute to all skygazers around the world who enjoy exploring the night sky with their telescopes,” said Babak Tafreshi, an astronomer, journalist and director of The World at Night (TWAN). “I’m happy to release this in April 2012 in celebration of the Global Astronomy Month, an international program of Astronomers Without Borders in partnership with world-wide astronomy centers and clubs.”
Continue reading “Timelapse: A Tribute to Sky Gazers”