According to AAVSO Special Notice #212: “Hiroshi Matsuyama (MTH), Kanimbla, Queensland, Australia, reports and Rod Stubbings (SRX), Tetoora Road, Victoria, Australia, confirms that the SU UMa-type dwarf nova QZ Vir (formerly called T Leo) is in outburst, and possibly in superoutburst.”
Matsuyama reported it at visual magnitude 10.4 on July 9.409 UT (JD 2455386.909), and Stubbings at visual magnitude 10.0 on July 11.384 (JD 2455388.884).
According to observations in the AAVSO International Database, the last regular outburst of QZ Vir, which is 16th magnitude at quiescence, occurred 4 July 2009 (JD 2455017, magnitude 10.6, Matsuyama), when it reached visual magnitude 10.3 and faded to 15th magnitude by 9 July (2455022). The last superoutburst (see AAVSO Special Notice #144) occurred between 19 January 2009 (JD 2454851, magnitude <14.0, Stubbings) and 21 January 2009 (JD 2454853, 10.97V, R. Diethelm, Rodersdorf, Switzerland), when it reached magnitude 10.0 and returned to 16th magnitude by 1 March 2009 (2454862).
If it is a superoutburst, superhumps will develop. All observations, including both visual estimates and CCD time-series photometry, are strongly encouraged at this time.
Coordinates: RA 11:38:26.80 Dec +03:22:07.0
Many thanks for your valuable observing efforts and observations!
This AAVSO Special Notice was prepared by Elizabeth O. Waagen.
Greetings, fellow SkyWatchers! Hopefully the rains have passed in your area and you’re ready for some dark skies and a double-dip… Double stars that is! This weekend we’ll take a look at some of the most colorful and interesting binary stars of the summer. Need more? Then hang tight as we take a look at one of the most concentrated globular clusters aroumd! Whenever you’re ready, I’ll see you in the backyard…
July 2, 2010 – This date marks the 1820 passing of British optician Peter Dollond, inventor of the triple achromatic lens. Dollond’s improvements to the refracting telescope included placing convex lenses of crown glass on either side of a biconcave flint glass lens to make the achromatic triplet lens we know today!
Now turn binoculars or telescopes toward magnitude 2.7 Alpha Librae, the second brightest star in the celestial ‘‘Scales.’’ Its proper name is Zuben El Genubi, and, as Star Wars as that sounds, the ‘‘Southern Claw’’ is actually quite close to home at a distance of only 65 light-years. No matter what size optics you are using, you’ll easily see Alpha’s widely spaced 5th magnitude companion, which shares the same proper motion. Alpha itself is a spectroscopic binary, as was verified during an occultation event, and its inseparable companion is only a half-magnitude dimmer according to the light curves. Enjoy this easy pair tonight!
July 3, 2010 – Tonight let’s go deep south and have look at an area that once held something almost half a bright as tonight’s later Moon and over four times brighter than Venus. Only one thing could light up the skies like that—a supernova.
According to historical records from Europe, China, Egypt, Arabia, and Japan, 1,003 years ago the very first supernova event was noted. Appearing in the constellation of Lupus, it was at first believed to be a comet by the Egyptians, yet the Arabs saw it as an illuminating ‘‘star.’’
Located less than a finger-width northeast of Beta Lupi (RA 15 02 48 Dec –41 54 42) and half a degree east of Kappa Centaurus, no visible trace is left of a once-grand event that spanned 5 months of observation, beginning in May and lasting until it dropped below the horizon in September 1006. It is believed that most of the star was converted to energy, and very little mass remains. In the area, a 17th magnitude star that shows a tiny gas ring and radio source 1459-41 remains our best candidate for pinpointing this incredible event.
Why you’re at it, try a challenging double star—Upsilon Librae (RA 15 37 01 Dec –28 08 06). This beautiful red star is right at the limit for a small telescope, but quite worthy, as the pair is a widely disparate double. Look for the 11.5-magnitude companion to the south in a very nice field of stars!
July 4. 2010 – Tonight let’s have a look at 400-lightyear-distant Rasalgethi—Alpha Herculis (RA 17 14 38 Dec +14 23 25). Known as the ‘‘Head of the Kneeling One,’’ it’s an easily resolved double and is noted for its fine color contrast. At magnitude 3.5, the variable bright primary is one of the largest known stars, with a diameter four times the Earth–Sun distance. Rasalgethi’s photospheric temperature is so low (3,000 Kelvin) that it barely glows a warm reddish orange. Meanwhile, its 5.4-magnitude companion is a yellow giant with a temperature twice the primary. The two together make Rasalgethi A seem a deeper red, while Rasalgethi B takes on a lovely yellow-green hue.
Need some fireworks? Then check out a single small globular—M80 (RA 16 17 02 Dec –22 58 30). Located about 4 degrees northwest of Antares (about two finger-widths), this little globular cluster is a powerpunch. Located in a region heavily obscured by dark dust, M80 will shine like an unresolvable star to small binoculars, but reveal itself to be one of the most heavily concentrated globulars in the telescope. Discovered within days of each other by Messier and Mechain, respectively, in 1781, this intense Class I globular cluster is around 36,000 light-years distant.
In 1860, M80 became the first globular cluster that was known to host a nova. As stunned scientists watched, a centrally located star brightened to magnitude 7 over a period of days, becoming known as T Scorpii. The event then dimmed more rapidly than expected, making observers wonder exactly what they had seen. Since most globular clusters’ stars are all about the same age, the hypothesis was put forward that perhaps they had witnessed an actual collision of stellar members. Given that the cluster contains more than a million stars, the probability is that some 2,700 collisions of this type may have occurred during M80’s lifetime.
Have a super weekend!
This week’s awesome images are: Zuben El Genubi, Field of SN1006, Upsilon Librae, Rasalgethi and M80. All done by Palomar Observatory, courtesy of Caltech. We thank you so much!
Greetings, fellow SkyWatchers! If we can keep the clouds and rain away, this will be an incredible weekend to enjoy some peaceful and relaxing time under the Moon and stars. We’ll begin with a heads up on a partial lunar eclipse whose beginning – or end – will be visible to most of us. Check your times carefully, because this one crosses the international date line! While you’re out, take a look at the lunar surface for some very interesting craters – or just relax with binoculars and suck in the photons of some curious variable stars. Are you ready? Then I’ll see you in the back yard…
June 25, 2010 – Today celebrates the birth of Hermann Oberth. Born in 1894 on this date, Oberth is considered to be the father of modern rocketry and space travel. But you won’t need a rocket to travel skyward as we gear up for the 2010 partial lunar eclipse!
A major section of western North and South America is in for treat as they will be able to see the beginning stages. These areas include Western Brazil, western Venezuela, and South American countries west of these locations. Believe it or not, a section of the southeastern United States will even be able to witness the eclipse – if it’s not raining!
The dividing line runs through the state of Georgia following a diagonal path north to Minnesota. States west of this line will also be within range of seeing the entire event until sunrise. On the west coast of the United States, the Moon will slide into umbral eclipse at 3:16 a.m. PDT, be deepest in shadow at 4:38 a.m. PDT, and the eclipse ends at 6:00 a.m. PDT – right about dawn. Locations that will be able to see the entire partial eclipse include the Pacific islands such as Hawaii, Polynesia, Fiji, Marshall Islands, New Zealand, Papua New Guinea, Australia, and most of Japan and the Philippines. Regions such as eastern China, the east edge of the USSR, Indonesia and the Thailand area will be able to see the very end of the 2010 partial lunar eclipse.
Despite bright skies tonight, take out your binoculars and look for a circlet of seven stars that reside about halfway between orange Arcturus and brilliant blue-white Vega. This quiet constellation is named Corona Borealis, or the Northern Crown.
Just northwest of its brightest star is a huge concentration of over 400 galaxies that reside over a billion light-years away from us. Known as Abell 4065, the Corona Borealis Galaxy Cluster is an area so small in apparent size that from our point of view we could eclipse it with a small coin held at arm’s length!
June 26, 2010 – Happy Birthday, Charles Messier! Born in 1730 on this date, almost everyone recognizes the name of this French astronomer who discovered 15 comets. He was the first to compile a systematic catalog – the ‘‘M objects.’’ The Messier Catalogue (1784) contains 103 star clusters, nebulae, and galaxies. But did you know Lyman Spitzer, Jr, shared this birthday? Born in 1914, Spitzer advanced our knowledge of physical processes in interstellar space and pioneered efforts to harness nuclear fusion as a clean energy source. He studied star-forming regions and suggested that the brightest stars in spiral galaxies formed recently. Not only that, but Spitzer was the first person to propose placing a large telescope in space, and so launched the development of the Hubble Space Telescope!
Tonight the mighty Moon will still rule the sky, providing a wonderful opportunity for casual inspection. Why not grab a telescope and view the lunar surface for a couple of telescopic challenges that are easy to catch? All you have to know is Mare Crisium!
On the southeastern shoreline is a peninsula that reaches into Crisium’s dark basin. This is Promontorium Agarum. On the western shore, bright Proclus lights the banks, but look into the interior for the two dark pockmarks of Pierce to the north and Picard to the south. Be sure to mark them on your notes!
When you’re finished, point your binoculars or telescopes back toward Corona Borealis and about three finger-widths northwest of Alpha for variable star R (RA 15 48 35 Dec +28 09 24). This star is a total enigma. Discovered in 1795, most of the time R carries a magnitude near 6 but can drop to magnitude 14 in a matter of weeks – only to unexpectedly brighten again! It is believed that R emits a carbon cloud, which blocks its light. Oddly enough, scientists can’t even accurately determine the distance to this star! When studied at minimum, the light curve resembles a ‘‘reverse nova’’ and has a peculiar spectrum. It is very possible that this ancient Population II star has used all of its hydrogen fuel and is now fusing helium to form carbon.
July 27, 2010 – Tonight we’ll again honor the June 26 birth of Charles Messier by heading toward the lunar surface first, in order to pick off another study object on our list – the twin crater pair Messier and Messier A.
Located in Mare Fecunditatis about a third of its width from west to east, these two craters will be difficult to find in binoculars, but not hard for even a small telescope and intermediate power. Indeed named for the famed French astronomer, the easternmost crater is somewhat oval in shape, with dimensions of 9 by 11 kilometers. At high power, Messier A to the west appears to have overlapped a smaller crater during its formation; and it is slightly larger at 11 by 13 kilometers. Although it is not on the challenge list, you’ll find another point of interest to the northwest. Rima Messier is a long surface crack, which runs diagonally across Mare Fecunditatis’s northwestern flank and reaches a length of 100 kilometers.
For variable star fans, let’s return to and focus our attention on S Coronae Borealis, located just west of Theta and the westernmost star in the constellation’s arc formation (RA 15 21 23 Dec +31 22 02). At magnitude 5.3, this long-term variable takes almost a year to go through its changes – usually far outshining the 7th magnitude star to its northeast – but will drop to a barely visible magnitude 14 at minimum. Compare it to the eclipsing binary U Coronae Borealis about a degree northwest. In slightly over 3 days, this Algol-type will range by a full magnitude as its companions draw together.
Until next week? Wishing you clear skies!
This article’s awesome illustrations are: Eclipse Chart courtesy of NASA, Abell 4065, R CorBor and S CorBor from Palomar Observatory, courtesy of Caltech, Lyman Spitzer historical image, Crisium in Decline courtesy of Shevill Mathers and Messier craters by Damien Peach. We thank you so much!
An artist's rendering of a Kuiper Belt object. Image: NASA
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How do you study an extremely small planetary body in the dim outer reaches of our solar system? Get all your friends from around the world to wait for a very elusive – if not short-lived – special event. And in doing so, you may find something completely unexpected. Enter James Elliot from MIT, who worked with dozens of observatories and astronomers across the globe, including Jay Pasachoff from Williams College in Massachusetts, in an attempt to make observations of the Kuiper Belt Object 55636, (also known as 2002 TX300) a small body orbiting about 48 AU away from the Sun. Since this KBO is too small and distant for direct observations of its surface, the astronomers tracked and plotted its course, figuring out when it would pass in front of a distant star.
The KBO occulted, or passed in front of a bright background star, an event which lasted only 10 seconds. But in that short amount of time, the astronomers were able to determine the object’s size and albedo. Both of these results were surprising.
55636 was found to be smaller than previously thought, 300km in diameter, but it is highly reflective, meaning it is covered in fresh, white ice.
Most known KBOs have dark surfaces due to space weathering, dust accumulation and bombardment by cosmic rays, so 55636’s brightness implies it has an active resurfacing mechanism, or perhaps that in some cases, fresh water ice can persist for billions of years in the outer reaches of the Solar System. One graph of the occultation from the Las Cumbres Observatory. Credit: Elliot, et al.
42 astronomers from 18 observatories located in Australia, New Zealand, South Africa, Mexico and the US were part of the observations, but because of weather and timing, only two observatories, both in Hawaii, were able to detect the occultation. Working with Wayne Rosing, Pasachoff coordinated the observations at the Las Cumbres Observatory Global Telescope Network located at Haleakala Crater on Maui, Hawaii, which made the best observations.
But Pasachoff told Universe Today that having two different angles of view to work with provided the ability to make quite precise measurements of the KBO.
“It was absolutely crucial to have the second observation site,” he said. “Without it, we
would not have known where on a round or elliptical body the chord, the line of occultation, passed and we could not have set an upper limit to the size of the body.”
A chord near the edge of a huge body can be vanishingly small, Pasachoff added, illustrating why they needed at least two chords.
Although the surfaces of other highly reflective bodies in the solar system, such as the dwarf planet Pluto and Saturn’s moon Enceladus, are continuously renewed with fresh ice from the condensation of atmospheric gases or by cryovolcanism that spews water instead of lava, 55636 is too small for these mechanisms to be at work.
“The surprising thing in a billion-year-old object that is so reflective is that it maintained or renewed its reflectivity,” said Pasachoff, “so possibilities include the darkening that we know takes place in the inner solar system is much less way out there; or the object renews its ice or frost from inside. We need new observations or more KBO’s with occultations, and we need more theoretical work.”
This was the first successful “planned” observation of a KBO using the stellar occultation method. In 2009 another team scoured through four and a half years of Hubble data to find on occultation of an extremely small KBO 975 meters (3,200 feet) across and a whopping 6.7 billion kilometers (4.2 billion miles) away.
For several years, Pasachoff and his team from Williams College have worked with Elliot and others from MIT, as well as Amanda Gulbis of the South African Astronomical Observatory to study Pluto by occultation. With careful measurements of a star’s brightness as Pluto hides or occults it, they have shown that Pluto’s atmosphere was slightly warming or expanding. A main goal now is to find out how the atmosphere is changing. This will be especially significant with the New Horizons spacecraft en route to Pluto.
Pasachoff said he knew 55636’s albedo would be bright, but was surprised how bright it was. The origins of this object is believed to come from a collision that occurred one billion years ago between one of the three known dwarf planets in the Kuiper Belt, Haumea and another object that caused Haumea’s icy mantle to break into a dozen or so smaller bodies, including 55636.
“Mike Brown (KBO and dwarf planet hunter from Caltech) told me last year, before the observations, that the object would be reflective since it is in the Haumea family, and Haumea itself has a high albedo,” Pasachoff said.
Pasachoff worked with Brown and his team last year in trying to capture the mutual occultations of transits of Haumea with its moon Namaka using the Palomar 5-meter telescope, but they weren’t successful in detecting the extremely small effect, given Haumea’s rapid rotation period.
Elliot used the occultation method to discover the rings of Uranus decades ago and continues to champion the method.
Pasachoff said the recent observation of 55636 was very rewarding. “It was an incredible observation, and I was very pleased to be part of it.” He said. “I am proud that all three of the graphs in the Nature article, and both of the successful observations, were arranged or made by our Williams College team.”
He added that any such observation includes at least these four elements: astrometric predictions, observations, reduction of data, interpretation.
“We were very fortunate and interested in being successful with observations,” Pasachoff said. “But it is important to note that Jim Elliot and his colleagues at MIT and Lowell Observatory have been working for years to refine the methods of predictions to get them accurate enough for this purpose. And this event was the first time that the predictions had been accurate enough to merit the all-out press of telescopes that we assembled. That we picked up the event, near the center of the prediction to boot, is a credit to the astrometry team.”
Greetings, fellow Stargazers! Have you been enjoying the rain? Then keep your eyes open for a “celestial shower” as meteoritic activity picks up over the next few nights, culminating in the peak of the Ophiuchid meteor Saturday night through Sunday morning. While you’re out relaxing, be sure to spare some time for lunacy and take a look some interesting features on the Moon. Need a test of your telescope’s resolving power? Then I “double dare” you to take on Gamma Virginis! Whenever you’re ready, I’ll see you in the back yard….
Friday, June 18, 2010 – Let’s begin the day by recognizing the 1799 birth on this date of William Lassell, telescope maker and discoverer of Triton (a moon of Neptune), and Ariel and Umbriel (satellites of Uranus). As often happens, great astronomers share birth dates, and this time it’s 187 years later for Allan Rex Sandage. A Bruce Medalist, Dr. Sandage is best known for his 1960 optical identification of a quasar, with his junior colleague, Thomas Matthews.
Our telescope lunar challenge tonight will be Hadley Rille. Find Mare Serenitatis and look for the break along its western shoreline that divides the Caucasus and Apennine mountain ranges. South of this break is the bright peak of Mons Hadley, which is of great interest for several reasons, so power up as much as possible.
Impressive Mons Hadley measures about 24 by 48 kilometers at its base and reaches up an incredible 4,572 meters. If volcanic activity had created it, Mons Hadley would be comparable to some of the very highest volcanically formed peaks on Earth, like Mount Shasta and Mount Rainer. South is the secondary peak, Mons Hadley Delta. It is home to the Apollo 15 landing site just a breath north of where it extends into the cove created by Palus Putredinus. Along this ridge line and smooth floor, look for a major fault line, winding its way across 120 kilometers of lunar surface; this is Hadley Rille. In places, the Rille spans 1,500 meters in width and drops to a depth of 300 meters below the surface. Believed to have been formed by volcanic activity 3.3 billion years ago, we can see the impact lower gravity has on this type of formation. Earthly lava channels are usually less than 10 kilometers long, and only around 100 meters wide. During the Apollo 15 mission, Hadley Rille was visited at a point where it was only 1.6 kilometers wide, still a considerable distance. Over a period of time, the Rille’s lava may have continued to flow through this area, yet it remains forever buried beneath years of regolith.
Saturday, June 19, 2010 – Tonight on the Moon we’ll be looking for another challenging feature and the craters that conjoin it—Stofler and Faraday. Located along the terminator to the south, crater Stofler was named for Dutch mathematician and astronomer Johan Stofler.
Consuming lunar landscape with an immense diameter of 126 kilometers, and dropping 2,760 meters below the surface, Stofler is a wonderland of small details in an eroded surrounding. Breaking its wall on the north is Fernelius, but sharing the southeastern boundary is Faraday. Named for English physicist and chemist Michael Faraday, this crater is more complex and deeper (4,090 meters) but far smaller in diameter (70 kilometers). Look for myriad smaller strikes that bind the two together!
When you’re done, let’s have a look at a delightful pair—Gamma Virginis (RA 12 41 41 Dec +01 26 54). Better knownas Porrima , this is one cool binary whose components are of almost equal spectral type and brightness. Discovered by Bradley and Pound in 1718, John Herschel was the first to predict this pair’s orbit in 1833, and stated that one day they would become inseparable to all but the very largest of telescopes—and he was right. In 1920 the A and B stars had reached their maximum separation, and during 2007 they were as close together as they ever can be. Observed as a single star in 1836 by William Herschel, its 171-year orbit puts Porrima in almost the same position now as it was when Sir William saw it!
Sunday, June 20, 2010 – In the predawn hours, we welcome the ‘‘shooting stars’’ as we pass through another portion of the Ophiuchid meteor stream. The radiant for this pass lies nearer Sagittarius, and the fall rate varies from 8 to 20 per hour, but the Ophiuchids can sometimes produce more than expected! Perhaps the sky acknowledges the 1966 passing of Georges Lemaitre on this date? Lemaitre researched cosmic rays and the three-body problem and in 1927 formulated the Big Bang theory using Einstein’s theories.
Are you ready to explore some more history? Then tonight have a look at the Moon and identify Alphonsus; it’s the centermost in a line of rings and looks much like the Theophilus, Cyrillus, and Catharina trio.
Alphonsus is a very old Class V crater, spans 118 kilometers in diameter, drops below the surface to about 2,730 meters, and contains a small central peak. Eugene Shoemaker had studied this partially flooded crater and found dark haloes on the floor. Again, this could be attributed to volcanism. Shoemaker believed they were maar volcanoes, and the haloes were dark ash. Power up and look closely at the central peak, for not only did Ranger 9 hard land just northeast, but this is the only area on the Moon where an astronomer has observed a change and backed up that observation with photographic proof.
On November 2, 1958, Nikolai Kozyrev long and arduous study of Alphonsus was about to be rewarded. Some two years earlier Dinsmore Alter had taken a series of photographs from the Mt. Wilson 60’’ reflector that showed hazy patches in this area that could not be accounted for. Night after night, Kozyrev continued to study at the Crimean Observatory, but with no success. During the process of guiding the scope for a spectrogram, the unbelievable happened—a cloud of gaseous molecules containing carbon had been captured! Selected as the last target for the Ranger series of photographic missions, Ranger 9 delivered 5,814 spectacular high-resolution images of this mysterious region before it crashed nearby. Capture it yourself tonight!
Until next time? Ask for the Moon… But keep on reaching for the stars!
This week’s awesome images are (in order of appearance): Dr. Alan Sandage courtesy of Dr. Sandage, Hadley Rille, courtesy of Wes Higgins, Stoffler and Faraday courtesy of Wes Higgins, Porrima – Palomar Observatory courtesy of Caltech, Georges Lemaitre and Albert Einstein (historical image), Ranger 9 Image of Alphonsus taken 3 minutes before impact courtesy of NASA, Alphonsus’ central peak taken 54 seconds before Ranger 9 impact courtesy of NASA. We thank you so much!
Noctilucent clouds over Kendal Castle, England in June 2010. Credit: Stuart Atkinson
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It’s summer (well, OK, technically next week it is summer) but it’s the time of year that northern latitudes can see the beautiful, awe inspiring atmospheric phenomena called Noctilucent Clouds, or night shining clouds. They aren’t like regular cumulus or cirrus clouds, but are mysterious and unique high atmosphere cloud formations thought to be composed of small ice-coated particles. How they form and why is not well understood, and usually the best time to see them is at twilight when the high altitude clouds are backlit by the sun. But Stu Atkinson in England sent in these great images of NLC’s, which he took in the wee hours of the morning (he woke up at 1:30 am) from the stunning location of Kendal Castle. He’s got more at his website, Cumbrian Sky.
Noctilucent clouds in Lancashire taken by Mark Purvis in 2009.
This image was sent in by UT reader Mark Purvis, who wrote, “This is an image I took in Beacon point in Lancashire. It was taken on the 21st July 2009 at 23:30(ish) with an Olympus E-400.”
Another look at Noctilucent clouds over Kendal Castle, England. Credit: Stuart Atkinson
If you have taken some images of NLC’s send them to Nancy and we’ll post them.
And here’s some observing tips from Spaceweather.com: Look west 30 to 60 minutes after sunset when the Sun has dipped 6 degrees to 16 degrees below the horizon. If you see luminous blue-white tendrils spreading across the sky, you may have spotted a noctilucent cloud. High-northern latitudes are favored.
Artist concept of Kepler in space. Credit: NASA/JPL
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The Kepler spacecraft has found over 750 candidates for extrasolar planets, and that is just from data collected in the first 43 days of the spacecraft’s observations. “This is the biggest release of candidate planets that has ever happened,” said William Borucki, Kepler’s lead scientist. “The number of candidate planets is actually greater than all the planets that have been discovered in the last 15 years.”
This is an astounding amount of potential exoplanets from data taken during such a short period of time, however Borucki added that they expect only about 50% of these candidates to actually turn out to be planets, as some may be eclipsing binary stars or other artifacts in the data. But still, even half would be the biggest group discovery of exoplanets ever.
And the exciting part is that 706 targets from this first data set have viable exoplanet candidates with sizes from as small as Earth to around the size of Jupiter. The team says the majority have radii less than half that of Jupiter.
The Kepler team has found so many candidates, they are sharing. They will keep the top 400 candidates to verify and confirm with observations using other telescopes – with observations done by Kepler team members. And today they have released the other 350 candidates, including five potential multiple planet systems.
However, some astronomers are upset about this and think the Kepler team should release all of their findings from the first year, as is typically done with NASA data.
Kepler launched on March 6, 2009, and has been on the hunt for exoplanets. Of course, the holy grail is finding an Earth-like or Earth-sized planet, especially those in the habitable zone of stars where liquid water and possibly life might exist. In the spring of 2009 the Kepler Mission conducted high precision photometry on nearly 156,000 stars to detect the frequency and characteristics of small exoplanets. Kepler studied an area in the constellation Cygnus, looking for the small changes in light that would signal a planet passing in front of its star.
But it takes time to verify candidates and find out if they are actually exoplanets. Usually, confirming the transit of an extrasolar planet requires observations of three different transits. While NASA’s policy requires astronomers to release their data from NASA instruments in a year, the Kepler team has worked out an agreement with the space agency so they can keep a certain portion of their data until they actually have time to verify this huge amount of exoplanet data. Between launch delays of other telescopes, cloudy nights for Earth based telescopes, and viewing a part of the sky that is only visible from the ground from April until September, they haven’t had the observing time they needed to check out all their planet candidates. The extension of the deadline gives the Kepler team the time to make sure they have gone through and found all the false positives and other potential misinterpretations of the Kepler data.
Dennis Overbye in the New York Times has written an article that delves more deeply into this little controversy. What is propriety data, and what is public? It’s a tough argument either way: scientists who have put years of their life into building a spacecraft should have the time they need to verify their data. But others feel the science should be open and available, and a policy is a policy: the deadline for releasing the data is here.
Whatever your feelings on open or closed data (and the Kepler team is only getting an extra six months on just part of their data, by the way), you have to be impressed with the quantity of potential exoplanet finds. And Kepler still has at least two years left of observations.
The composite image from 11 images, each with 5 sec exposure, spaced by 35-50 sec. The magnitude of Hayabusa is estimated to be 21 mag. Credit: Subaru Telescope Team
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The world watched and waited for the Hayabusa spacecraft to make its return to Earth on June 13, 2010 and the people of Japan — who built and launched the little spacecraft that could (and did!) — were especially hopeful in watching and waiting. Japan’s Subaru Telescope (although located on Mauna Kea in Hawaii) turned its expectant eyes towards Hayabusa and captured the spacecraft’s flight between the Moon and Earth in 11 different images.
A note from the Subaru Telescope team:
During the busy time preparing the observations, Doctor Masafumi Yagi and his team managed to maneuver the telescope just in time to catch Hayabusa before it disappeared down south in the twilight sky. At that time, Hayabusa was a little less than half way between Moon and Earth. Five seconds exposures, each spaced by 35 – 50 seconds in the V filter with Suprime Cam, it showed up in clear trace at the position expected to be. Brightness is estimated to be only 21 magnitudes. At this level, one can see a background galaxy clearly.
We are waiting to hear more from the project team at ISAS/JAXA. In the meantime, congratulations to all who are involved in this unprecedented endeavor.
And here are some images of the recovery teams who picked up the sample return canister in the Woomera Prohibited Area in Australia. The canister will be taken to Japan and opened in a few weeks, or perhaps months, after rigorous testing. Only then will we find out if any asteroid samples made it in the canister for the ride back to Earth.
Recovery team makes sure all is safe with the sample return canister. Credit: JAXAThe recovery team handles the heat sheild for the Hayabusa sample return capsule. Credit: JAXA, Hayabusa Twitter feed.JAXA's Hayabusa space capsule is transported inside a box to a clean room inside the Instrumentation Building at the Woomera Test Range, South Australia. Credit: Australian Science Media Centre
Greetings, fellow SkyWatchers! Sorry to be so late, but satellite internet connections and electrical storms don’t mix! Even though there’s not a snowball’s chance in the desert of observing here tonight, don’t let that stop you from enjoying some of the finest galaxies you’ll ever trip the light fantastic with! Find yourself a dark sky site and enjoy three of my favorites of the season… and share your observations! This time I’ll join you in your backyard….
June 4, 2010 – Did you ever wonder who was the first to organize an astronomy group? No less a personage than Baron Franz Xaver Freiherr von Zach. Born on this date in 1754, von Zach was the director of an observatory near Gotha, and in 1798 he organized the first congress of astronomers, with Joseph LaLande as the honored guest. He later formed another group of two dozen astronomers to help locate the ‘‘missing planet’’ between the orbits of Mars and Jupiter. I wonder what they discovered?
Tonight we’ll head toward Leo for another galaxy worth a visit. . . and even binoculars can spot it! You’ll need to identify slightly fainter Lambda to the southwest of Epsilon and head south about one finger-width for NGC 2903 (RA 09 32 09 Dec +21 30 02). William Herschel discovered this awesome oblique spiral galaxy in 1784. At slightly brighter than magnitude 9, it’s in easy range of most binoculars. It is odd that Messier missed this one, considering both its brightness and the fact that three of the comets he discovered passed by it! Perhaps it was cloudy when Messier was looking, but we can thank Herschel for cataloging NGC 2903 as H I.56.
Although small optics will only perceive this 25-million-light-year-distant beauty as a misty oval with a slightly brighter core region, larger aperture will light this baby up. Soft suggestions of its spiral arms and concentration will begin to appear. One such knot is star cloud NGC 2905—a detail in a distant galaxy so prominent that it received its own New General Catalog designation. NGC 2903 is roughly the size of our own Milky Way and includes a central bar, yet the nucleus of our distant cousin has ‘‘hot spots’’ that were studied by the HST and extensively by the Arecibo telescope. Although our own galactic halo is filled with ancient globular clusters, this galaxy sports brand new ones! Be sure to mark your notes with your observations, because many different organizations consider this to be on their ‘‘Best of’’ lists.
June 5, 2010 – Let’s take a look at John Couch Adams, a discoverer of Neptune who was born on this date in 1819. Said he: ‘‘. . .the beginning of this week of investigating, as soon as possible after taking my degree, the irregularities in the motion of Uranus. . .in order to find out whether they may be attributed to the action of an undiscovered planet beyond it.’’ But that’s not all Adams contributed! He was the first to associate the Leonid meteor shower with the orbital path of a comet, and he also observed the Moon.
Tonight we’ll take a look at our moving universe, and we begin by locating 5th magnitude 6 Comae Berenices about three finger-widths east of Beta Leonis. Remember this star! We are going on a galaxy hop to a Mechain discovery that is less than a degree west, and its designation is M98 (RA 12 13 48 Dec +14 53 58). At magnitude 10, this beautiful galaxy is a telescope-only challenge and a bit on the difficult side for small aperture. Long considered part of the Virgo Cluster , M98 is approaching us at a different rate than other cluster members, giving rise to speculation that it may simply be in the line of sight. Quite simply put, it has a blue shift instead of red! But considering that all these galaxies (and far fainter ones than we can see), are in close proximity leads some researchers to believe it is a true member by virtue of the extreme tidal forces that must exist in the area—pushing it toward us at this point in time, rather than away.
In a small telescope, M98 will appear like a slim-line with a slightly brighter nucleus, a characteristic of an edge-on galaxy. To large aperture, its galactic disk is hazy and contains patchiness in structure. These are regions of newly forming stars and vast regions of dust, yet the nucleus remains a prominent feature. M98 is a very large galaxy, so be sure to use a minimum of magnification and plenty of aversion to make out small details in this fine Messier object!
June 6, 2010 – Today we begin with the 1932 birth on this date of David Scott, the seventh person to walk on the Moon and the first to ride the Lunar Rover on the surface during the Apollo 15 mission. Sharing his birth date, but almost 500 years earlier, was the astronomer Regiomontanus (1436). Regiomontanus made observations of a comet, which were accurate enough to associate it with Comet Halley 210 years later, and his interest in the motion of the Moon led him to make the important observation that lunar distances could be used to determine longitude at sea!
No galactic tour through Coma Berenices would be complete without visiting one of the most incredible ‘‘things that Messier missed.’’ You’ll find NGC 4565 (RA 12 36 21 Dec +25 59 13) located less than 2 degrees east of 17 Comae. Residing at a distance of around 30 million light-years, this large 10th magnitude galaxy is probably one of the finest edge-on structures you will ever see. Perfectly suited for smaller scopes, this ultra-slender galaxy with the bright core has earned its nickname of the ‘‘Needle.’’ Although photographs sometimes show more than what can be observed visually, mid-to-large aperture can easily trace out NGC 4565’s full photographic diameter.
Although Lord Rosse in 1855 saw the nucleus of the Needle as stellar, most telescopes will resolve a bulging core region with a much sharper point in the center and a dark dust lane upon aversion. The core itself has been extensively studied for its cold gas and emission lines, pointing to the fact that it has a barred structure. This is much how the Milky Way would look if viewed from the same angle! It, too, shines with the light of 30 billion stars. Chances are NGC 4565 is an outlying member of the Virgo Cluster, but its sheer size points to the fact that it is probably closer than the others. If we were to place it at the accepted distance of 30 million years, its diameter would be larger than any galaxy yet known! Get acquainted with it tonight… Because big is beautiful, too!
Until next week? Keep reaching for the stars!
This week’s awesome images are (in order of appearance): NGC 2903, M98 and NGC 4565 are from Palomar Observatory, courtesy of Caltech. We thank you so much!
Greetings, fellow SkyWatchers! It’s a green “Corn Moon” weekend and time to get out of the house and enjoy the night sky! Enjoy sharing “Moon Illusion” with friends or simply spotting bright features with easy optics. In the mood to kick back and stargaze? The learn more about the constellation of Leo and what to look for when skies are bright. If you’re ready for a challenge, then try your hand at a few bright galaxies by holiday’s end. Whenever you’re ready, I’ll see you in the backyard….
May 28, 2010 – Today, we begin by saluting the 1930 birth on this date of Frank Drake, father of Project Ozma and formulator of the ‘‘Drake Equation,’’ used to estimate the number of technological civilizations that may exist in our galaxy. Dr. Drake also worked with Carl Sagan on the plaques placed aboard Pioneers 10 and 11, which greet any visitors the probes might encounter. Also remember Rudolph Leo B.Minkowski on this 114th anniversary of his birth. Minkowski studied spectra and contributed to the discovery of more than half of the planetary nebulae now known. Along with Walter S. Baade, Minkowski separated supernovae into spectral types and identified optical counterparts for early radio source galaxies.
Tonight is the ‘‘Full Flower Moon.’’ Earth is awakening again! Agricultural literature refers to it as the ‘‘Full Corn Planting Moon,’’ or the ‘‘Milk Moon.’’ No matter what it’s named, Moonrise is majestic to watch. Participate in a Lunar Club Challenge and do some outreach work by demonstrating ‘‘Moon Illusion’’ to someone. We know it’s purely psychological and not physical, but the fact remains that the Moon seems larger on the horizon. Using a small coin held at arm’s length, compare it to Luna as it rise, and then again as it seems to ‘‘shrink’’ as it moves up! You’ve now qualified for extra credit.
Try using colored or Moon filters to look at the many surface features that throw amazing patterns across its surface. If you have none, a pair of sunglasses will suffice. Look for things you might not ordinarily notice, such as the huge streak emanating from crater Menelaus, the pattern projected from Proclus, or the bright tiny dot of little-known Pytheas north of Copernicus. It’s hard to miss the blinding beacon of Aristarchus! Check the southeastern limb, where the edge of Furnerius lights up the landscape.. or how a nothing crater like Censorinus shines on the southeast shore of Tranquillitatis, while Dionysus echoes it on the southwest. Could you believe Manlius just north of central could be such a perfect ring, or that Anaxagoras would look like a northern polar cap? Although it might be tempting to curse the Moon for hiding the stars when it’s full, there is no other world outvthere that we can view in such detail – even if you just look with your eyes!
May 29, 2010 – Today we begin with the 1794 birth on this date of Johann Heinrich von Madler who, along with Wilhelm Beer, published the most complete map up to that time of the Moon, Mappa Selenographia. How fitting it is then, that we should have the bright Moon tonight! Before the Moon rises, take a look at the constellation of Leo and its brightest stars.
Our first destination is 85 light-year-distant Regulus. As the 21st brightest star in the night sky, 1.35-magnitude Alpha Leonis is a helium star about 5 times larger and 160 times brighter than our own Sun. Speeding away from us at 3.7 kilometers per second, Regulus is also a multiple system whose 8th magnitude B companion is easily seen in small telescopes. Regulus B is also a double, with a magnitude 12 dwarf companion of uncertain type. There’s an additional 13th magnitude star in this grouping, but it’s probably not associated with Regulus, since the ‘‘Little King’’ is moving toward it and will be very close to it in 800 years.
About a fist-width northeast of Regulus is 2.61-magnitude Gamma Leonis. Algieba is a very fine double star, but difficult to see at low power, since the 90 light-year distant pair is bright and close. Separated by about twice the diameter of our own Solar System, the gap between Algieba and its companion is slowly widening! Another two finger-widths north is 3.44-magnitude Zeta. Aldhafera is about 130 light-years away and also has an optical companion—35 Leonis. Remember this binocular pair, because they’ll lead you to galaxies later! Before we leave, look east for 3.34-magnitude Theta. Mark this one in your memory, because Chort and 3.94-magnitude Iota to the south serve as markers for a galaxy hop! Last is easternmost 2.14 magnitude Beta. Denebola is the ‘‘Lion’s Tail’’ and has several faint optical companions.
May 30, 2010 – Today we begin with the 1423 birth of Georg von Peuerbachon this date, a follower of Ptolemy’s astronomy. Georg calculated eclipses; observed Halley’s Comet before it was so named; and created astronomical instruments. Following Georg nearly half a millennium later was Hannes Alfven, born in 1908. Alfven’s life work was plasma and its electric and magnetic forces. Lastly, we have Aleksei Arkhipovich Leonov, who was born in 1934. Leonov was the first man to climb out of a spacecraft (the Voskhod II ) and into space. He was the first true ‘‘astrophotographer’’ as he filmed for 10 minutes while orbiting!
Tonight’s study is for mid- to large-aperture telescopes. Begin by heading west about a fist-width from Regulus and identify 52 Leonis. Our mark is 1.5 degrees south. At lower power, you’ll see a triangle of galaxies.
The largest and brightest is M105 (RA 10 47 49 Dec +12 34 54). This dense elliptical galaxy appears evenly distributed, but the Hubble Space Telescope (HST) revealed a huge mass within the core equal to about million suns. The companion elliptical to the northeast— NGC 3384—reveals a bright nucleus and an elongated form. The faintest of this group— NGC 3389—is a receding spiral; larger scopes will see ‘‘patchiness’’ in structure.
Continue another degree south and enjoy another galactic pair. The widely spaced M96 (RA 10 46 45 Dec +11 49 10) and M95 (RA 10 43 57 Dec +11 42 12) belong to a galaxy grouping called Leo I. The dusty spiral—M96—will appear as a silver oval, with a nucleus much sharper than its faint spiral arms. M96 hosted a supernova as recently as 1998. To its west, you’ll discover a beautiful barred spiral—M95—a prime target of the HST. Visually, we enjoy M95 for its unique ring-like arms and unmistakable barred core, but the HST was looking for Cepheid variables to help determine the Hubble constant. Although we don’t need a space telescope to view this group of galaxies, we can appreciate taking a 38-million-light-years journey from our own backyard!
Until next week? Dreams really do come true when you keep on reaching for the stars!
This week’s awesome photos are (jn order of appearance): Frank Drake (archival image), Full Moon courtesy of NASA, Leo courtesy of NASA, Aleksei Arkhipovich Leonov (archival image), M105 and M95 – Palomar Observatory, courtesy of Caltech. We thank you so much!
