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NASA's Mars Reconnaissance Orbiter have returned to Earth.
Time to head out into the astrosphere again.
First, I'd like to point your attention towards the very nicely done Carnival of Space #6, hosted by the Music of the Spheres. This themed carnival has a theme of its own, the International Space Development Conference, which recently wrapped up. I really enjoyed this edition, so check it out. (There's an article from me in there, somewhere).
Space Prizes has some information on a new SEDS Space Art Contest.
The European Southern Observatory has redesigned its website, with a new tagline, "Astronomy Made in Europea". The Apparent Brightness blog doesn't think that's exactly accurate.
Alan Boyle from MSNBC's Cosmic Log rounds up Hubble's greatest hits. You might be surprised at what made the list.
1,200 New Photos of Mars
I know there are tens of thousands of photographs of Mars already available, but that number just jumped up by about 1,200. Photos taken by NASA's Mars Reconnaissance Orbiter have been returned back to Earth and processed so that anyone with an Internet connection can browse through them.
This new dataset, captured by the High Resolution Imaging Experiment (HiRISE) camera, fills a whopping 1.7 terabytes of hard drive space. But don't worry, there's a handy set of tools you can use on the HiRISE site to quickly browse through them, and zoom in for more details, without having to tie up your Internet connection.
HiRISE captures 6 km-wide (3.5 mile) swathes of the Martian surface from an altitude of 250 to 316 km (155 and 196 miles). These images can show details as small as 1 metre across (40 inches).
Original Source: UA News Release
Astrosphere for July 6, 2007
Let's head out into the astrosphere and see what we can see.
Remember how I blogged about NASA Administrator's startling admission on NPR that he doesn't think global warming is a problem? Well, he's made the retraction he should have made earlier.
An enraged Dr. Pamela Gay reacts to the fact that three Republican presidential candidates don't believe in evolution. Oh, and the Milky Way has tidal tails.
Centauri Dreams thinks that we might we might be consuming our way into silence.
Hobbyspace has some cool pictures and information about a Japanese reusable prototype rocket vehicle.
Wil Wheaton likes the Bad astronomy blog. The Bad Astronomer loves Wil Wheaton. Awww...
You have no excuse to miss the Shuttle launch. MSNBC's Alan Boyle lists every single way to see it.
Geoengineering Comes with Huge Risks
Over the coming decades, we're going to learn what kind of impact global warming is going to have on planet Earth. If the impact is as severe as some scientists are predicting, countries might take drastic action to stabilize temperatures. But scientists from Concordia University and the Carnegie Institution think that tinkering with the Earth on a global scale - or geoengineering - is very bad idea, and could make the problem much worse.
In order to defend against global warming, some novel ideas have been proposed; here are a few: building a fleet of satellites to shade the planet, using mirrors to reflect light away, or releasing light-reflecting particles into the atmosphere to cool temperatures.
According to this new study, published in the June 4 Proceedings of the National Academy of Sciences, these projects could provide relief from rising temperatures, but they could worsen the situation if the projects fail or were suddenly halted. Even though temperatures would be cooled, greenhouse gas emissions would continue to rise. And if the projects failed, we could experience rates of warming 20 times what we are experiencing today.
For an analogy, let's say you want to keep your car cool, and put shades over the windows. If you take the shades off in the heat of the day, the car will heat up much more quickly than if you let it warm up slowly in over the course of the morning. This kind of drastic temperature increase would put even more of a strain on resources, wildlife, and human populations.
Here's what one of the researchers, Ken Caldeira, had to say:
The researchers aren't ruling out these kinds of megaprojects entirely, but they emphasize cutting down emissions as quickly as possible, not hoping to rely on a silver bullet.
Original Source: Carnegie Institution News Release
Astrosphere for June 5, 2007
Not much out in the 'sphere today. Strange, not much science news either. I guess everyone's recovering from the AAS meeting in Hawaii. You'd think going to Hawaii would be relaxing.
If anyone's interested, I'm looking for a part time assistant to help me gather together the news that makes up universe Today. I've got a post on the Bad Astronomy/Universe Today Forum explaining the opportunity.
The Daily Galaxy has a story on how a group of physicists think that the Big Bang might be cyclical.
Above the Clouds has a nice story and photograph about M13, the globular cluster in Hercules. It's one of my favourite skywatching targets.
A husband and wife team are planning their own trip to Mars. You'd say that's crazy, but they've already gone to the top of Everest. Hmm, that's pretty crazy too. The Space Fellowship has the story.
What's Up this Week: June 4 - June 10, 2007
Monday, June 4 - Tonight we'll use Rho Virginis as a stepping stone to more galaxies. Get on your mark and move one and a half degrees north for M59...
First discovered in 1779 by J. G. Koehler while studying a comet, this 11th magnitude elliptical Galaxy was observed and labeled by Messier who was just a bit behind him. Much denser than our own galaxy, M59 is only about one-fourth the size of the Milky Way. In a smaller telescope, it will appear as a faint oval, while larger telescopes will make out a more concentrated core region.
Now shift one half degree east for brighter and larger M60. Also caught first by Koehler on the same night as M59, it was "discovered" a day later by yet another Astronomer who had missed M59! It took Charles Messier another four days until this 10th magnitude Galaxy interfered with his comet studies and was cataloged.
At around 60 million light-years away, M59 is one of the largest ellipticals known and has five times more mass than our galaxy. As a study object of the Hubble Telescope, this giant has shown a concentrated core with over 2 billion solar masses. Photographed and studied by large terrestrial telescopes, M59 may contain as many as 5100 globular clusters in its halo.
While our backyard equipment is essentially revealing M59's core, there is a curiosity here. It shares "space" with spiral Galaxy NGC 4647. Telescopes of even modest aperture will pick up the nucleus and faint structure of this small face-on galaxy. Harlow Shapely found the pair odd because - while they are relatively close in astronomical terms - they are very different in age and development. Halton Arp also studied this combination of an elliptical Galaxy affecting a spiral and cataloged it as "Peculiar Galaxy 116." Be sure to mark your notes!
Tuesday, June 5 - Tonight we'll go back to Rho once again and about a fingerwidth northwest for yet another bright Galaxy - M58 - a spiral Galaxy actually discovered by Messier in 1779!
As one of the brightest galaxies in the Virgo cluster, M58 is one of only four that have barred structure. It was cataloged by Lord Rosse as a spiral in 1850. In binoculars, it will look much like our previously studied ellipticals, but a small telescope under good conditions will pick up the bright nucleus and a faint Halo of structure - while larger ones will see the central concentration of the bar across the core. Chalk up another Messier study for both binoculars and telescopes and let's get on to something really cool!
Around a half degree southwest are NGC 4567 and NGC 4569. L. S. Copeland dubbed them the "Siamese Twins," but this Galaxy pair is also considered part of the Virgo cluster. While seen from our viewpoint as touching galaxies, no evidence exists of tidal filaments or distortions in structure, making them a line of sight phenomenon and not interacting members. While that might take little of the excitement away from the "Twins," a supernova event has been spotted in NGC 4569 as recently as 2004.
While the duo is visible in smaller scopes as two, with soft twin nuclei, intermediate and larger scopes will see an almost V-shaped or heart-shaped pattern where the structures overlap. If you're doing double Galaxy studies, this is a fine, bright one! If you see a faint Galaxy in the field as well, be sure to add NGC 4564 to your notes.
For all you Stargazers, keep watch for the Scorpid meteor shower. Its radiant will be near the constellation of Ophiuchus, and the average fall rate will be about 20 per hour with some fireballs.
Wednesday, June 6 - So far we've studied many Herschel objects in disguise as Messier catalog items - but we haven't really focused on some mighty fine galaxies that are within the power of the intermediate to large telescope. Tonight let's take a serious skywalk as we head to 6 Comae and drop two degrees south.
At magnitude 10.9, Herschel catalog object H I.35 is also known by its New General Catalog number of 4216. This splendid edge-on Galaxy has a bright nucleus and will walk right out in larger telescopes with no aversion required. But, the most fascinating part about studying anything in the Virgo cluster is about to be revealed.
While studying structure in NGC 4216, averted vision picks up magnitude 12 NGC 4206 to the south. This is also a Herschel object - H II.135. While it is smaller and fainter, the nucleus will be the first thing to catch your attention - and then you'll notice it is also an edge-on galaxy! As if this weren't distracting enough, while re-centering NGC 4216, sometimes the movement is just enough to allow the viewer to catch yet another edge-on Galaxy to the north - NGC 4222. At magnitude 14, you can only expect to be able to see it in larger scopes, but what a treat this trio is!
Is there a connection between certain types of Galaxy structures within the Virgo cluster? Science certainly seems to think so. While low metallicity studies involving these galaxies are going on, research into evolution of Galaxy clusters themselves continue to make new strides forward in our understanding of the universe.
Capture them tonight!
Thursday, June 7 - If you're up before dawn the next two days or out just after sunset, enjoy the peak of the June Arietid meteors - the year's strongest daylight shower - with up to 30 visible per hour.
If you'd like to try your ear at radio astronomy with the offspring of sungrazing asteroid Icarus, tune an FM radio to the lowest frequency not receiving a clear signal. An outdoor antenna pointed at the zenith increases your chances, but even a car radio can pick up strong bursts! Simply turn up the static and listen. Those hums, whistles, beeps, bongs, and occasional snatches of signals are our own radio signals being reflected off the meteor's ion trail!
Tonight let's study a radio-source Galaxy so bright it can be seen in binoculars - 8.6 magnitude M87, about two fingerwidths northwest of Rho Virginis.
This giant elliptical was discovered by Charles Messier in 1781 and cataloged as M87. Spanning 120,000 light-years, it's an incredibly luminous Galaxy containing far more mass and stars than the Milky Way - gravitationally distorting its four dwarf satellites galaxies. M87 is known to contain in excess of several thousand globular clusters - up to 150,000 - and far more than our own 200.
In 1918, H. D. Curtis of Lick Observatory discovered something else - M87 has a jet of gaseous material extending from its core and pushing out several thousand light-years into space. This highly perturbed jet exhibits the same polarization as synchrotron radiation - a property of Neutron stars. Containing a series of small knots and clouds as observed by Halton Arp at Palomar in 1977, he also discovered a second jet in 1966 erupting in the opposite direction. Thanks to these two properties, M87 made Arp's "Catalog of Peculiar Galaxies" as number 152.
In 1954 Walter Baade and R. Minkowski identified M87 with radio source Virgo A, discovering a weaker Halo in 1956. Its position over an X-ray cloud extending through the Virgo cluster make M87 a source of an incredible amount of x-rays. Because of its many strange properties, M87 remains a target of scientific investigation. The Hubble has shown a violent nucleus surrounded by a fast rotating accretion disc, whose gaseous make-up may be part of a huge system of interstellar matter. As of today, only one supernova event has been recorded - yet M87 remains one of the most active and highly prized study galaxies of all. Capture it tonight!
Friday, June 8 - Born on this date in 1625 was Giovanni Cassini - the most notable observer following Galileo. As head of the Paris Observatory for many years, he was the first to observe seasonal changes on Mars and measure its parallax (and so, its distance). This set the scale of the solar system for the first time. Cassini was the first to describe Jovian features, and studied the Galilean moons' orbits. He also discovered four moons of Saturn, but he is best remembered for being the first to see the namesake division between the A and B rings.
Tonight let's honor Cassini by taking a look at both planets - beginning with the westering Saturn. To the unaided eye, this creamy-yellow "star" outshines most stars in the region and holds competition with Regulus in Leo. To binoculars, it reveals itself as a planet - one with ears! While great detail cannot be seen, even the slightest optical aid makes it a joy.
To the east, Jupiter is rising... But give it some time to clear the atmospheric distortion! By far brighter than neighboring stars to the unaided eye, giant Jupiter will move slowly along the ecliptic plane over the course of the evening. To smaller binoculars it is easily observed as an orb with two grey bands across the middle. To larger binoculars, the equatorial belts become much clearer and the four Galilean moons are easily seen with steady hands. To the small telescope, no planet offers greater details. Even at very low magnifying power, the north, south and central equatorial zones are easily observable and all four moons are clear and steady.
To the mid-sized telescope, far greater details begin to appear - such as temperate belts on the planet's surface and the soft appearance of the Great Red Spot. Finer details are visible during steady seeing, and small things like being able to see which satellite is closer to - or further away from - our vantage point become very easy. Simple things, like watching a Moon transit the surface and the resulting shadow on the planet are much easier. With a large telescope, Jupiter depends more on seeing conditions for details. While more aperture allows finer views - conditions are everything when it comes to the Mighty Jove!
Saturday, June 9 - Today is the birthday of Johann Gottfried Galle. Born in Germany in 1812, Galle was the first observer to locate Neptune. He is also known for being Encke's assistant - and he's one of the few Astronomers ever to have observed Halley's comet twice. Unfortunately, he died two months after the comet passed perihelion in 1910, but at a ripe old age of 98! I wonder if he knew Mark Twain?
For unaided observers, be sure to check out brilliant Venus as it reaches greatest elongation just after sunset!
Tonight while we're out, let's have a look at a Virgo Galaxy bright enough for smaller instruments and detailed enough to delight larger scopes. Starting at Delta Virginis, move about a fistwidth to the west where you will see two fainter stars, 16 (south) and 17 (north) Virginis. You'll find M61 located about one-half degree south of the yellow double star 17.
Its Discovery was credited to Barnabus Oriani during that fateful year of 1779 when Messier was so avid about chasing a comet that he mistook it for one. While Charles had seen it on the same night, it took him two days to figure out it wasn't moving and four more before he cataloged it. Fortunately, 7 years later Mr. Herschel assigned it his own number of H I.139, even though he wasn't fond of assigning his own number to Messier catalog objects.
At near 10th magnitude, this spiral Galaxy will show a slightly elongated form and brighter core area to small telescopes, and really come to life in larger ones. Close to our own Milky Way Galaxy in size, this larger member of the Virgo cluster has great spiral arm structure that displays both knots and dark dustlanes - as well as a beautifully developed nucleus region. M61 has also been host to four supernova events between 1926 and 1999 - all of which have been well within range of amateur telescopes.
For an added Herschel treat tonight for larger scopes, hop back to star 17 and head about one half degree due west for near galactic pair NGC 4281 (H II.573) and NGC 4273 (H II.569). Here is a study of two galaxies similar in magnitude (12) and size - but of different structure. Northeastern NGC 4281 is an elliptical, and by virtue of its central concentration will appear slightly larger and brighter - while southwestern NGC 4273 is an irregular spiral which will appear brighter in the middle but more elongated and faded along its frontiers. Sharp-eyed observers may also note fainter (13th magnitude) NGC 4270 north of this pairing.
Sunday, June 10 - Although no one likes to get up early, this morning will be a great time to catch the close pairing of Mars and the waning Moon!
While I'm sure that unaided eye viewers and binocular users are tired of the Galaxy hunt, be sure to take the time to look at many old favorites that are now in view. To the eye, one of the most splendid signs of the changing seasons is the Ursa Major Moving Group which sits above Polaris for northern hemisphere observers. For the southern hemisphere, the return of Crux serves the same purpose.
Old favorites have now begun to appear again, such as Hercules, Cygnus and Scorpius... and with them a wealth of starry clusters and nebulae that will soon come into view as the night deepens and the hour grows late. Before we leave Virgo for the year, there is one last object that is seldom explored and such a worthy target that we must visit it before we go. Its name is NGC 5634 and you'll find it halfway between Iota and Mu Virginis (RA 14 29.37 Dec -05 58.35)...First discovered by Sir William Herschel on March 5, 1785 and cataloged as H I.70, this magnitude 9.5 small globular cluster isn't for everyone, but thanks to an 11th magnitude line-of-sight star on its eastern edge, it sure is interesting. At class IV, it's more concentrated than many globular clusters, although its 19th magnitude members make it near impossible to resolve with backyard equipment.
Located a bit more than 82,000 light-years from our solar system and about 69,000 light-years from the galactic center, you'll truly enjoy this globular for the randomly scattered stellar field which accompanies it. In the finderscope, an 8th magnitude star will lead the way - not truly a member of the cluster, but one that lies between us. Capturable in scopes as small as 4.5", look for a concentrated central area surrounded by a haze of stellar members - a huge number of which are recently discovered variables. While you look at this globular, keep this in mind...
Based on observations with the Italian Telescopio Nazionale Galileo, it is now surmised that the NGC 5634 globular cluster has the same position and radial velocity as does the Sagittarius dwarf spheroidal galaxy. Because of the dwarf galaxy's metal-poor population of stars, it is believed that NGC 5634 may have once been part of the dwarf Galaxy - and been pulled away by our own tidal field to become part of the Sagittarius stream!
Mars Garden Wins at a Flower Show
I just think this is the coolest thing. But then, maybe I've gone a little crazy for gardening recently. A garden designed to simulate a future habitation on Mars won a Gold Medal at the Chelsea Flower Show, operated by the UK's Royal Horticultural Society. Finally, space exploration is getting a little respect.
The exhibit is called "600 Days with Bradstone", and it's a simulated garden that Martian astronauts might construct to help them cope with a long journey on the Red Planet. The designer consulted with the European Space Agency to understand the physical constraints for a domed garden on Mars. Rocks were quarried from Scotland that look realistically like Martian rocks.
After a hard day's work on the dusty surface of Mars, astronauts could enjoy a lush green garden, surrounded by plants with multiple beneficial properties, like coffee, olives, wheat and calendula. The garden also includes familiar plants that help remind the astronauts of their home.
ESA believes that future missions to Mars will require regenerative systems that can adapt and evolve over time, instead of traditional life support systems which can't operate at peak efficiency for the long durations required for a Mars mission.
Original Source: ESA News Release
Deathwatch on a red giant Star
When a star like our Sun reaches the end of its life - a fate we'll face in 5 billion years - it swells up immensely, becoming a red giant star. Its size expands until it engulfs everything within the Earth's orbit, and begins to pulsate, expending and contracting in regular intervals. Then it settles down, to live out the rest of its years as a slowly cooling white dwarf.
We've got 5 billion years to wait, but Astronomers have found a relatively nearby star going through this very process: S Orionis, located in the constellation of Orion, and belongs to a class of Mira-type variable stars.
S Orionis pulsates with a period of 420 days. During this cycle, it changes in brightness by a factor of 500%, and changes its diameter by 20%. This ranges from 1.9 to 2.3 times the distance between the Earth and the Sun. Another way to measure this is between 400 and 500 solar radii.
During these pulsations, the star releases a tremendous amount of dust, which form into concentric rings around the star and expand outward at a speed of 10 km/s (6 miles/s). During the star's minimum size, there's more dust production and coronal mass ejections, and then the shell expands, releasing the material into space.
Astronomers studied S Orionis with the European Southern Observatory's Very Large Telescope Interferometer at Paranal Observatory, Chile, using its four 8.2-metre telescopes and four 1.8-metre scopes.
Original Source: ESO News Release
Recent Landslide on Mars
With more advanced optics in orbit around Mars, we're getting better and better pictures showing how the planet is more active than scientists ever imagined. Here's a cool photograph of a recent landslide in a region of Mars called Zunil Crater. It was taken by the High Resolution Imaging Science Experiment (HiRISE) on board NASA's Mars Reconnaissance Orbiter.
Zunil Crater is a well-preserved impact crater approximately 10 km (6 miles) across. Because it's so well preserved, scientists think the crater was carved out by a meteor impact less than 10 million years ago - that's young, considering some of the craters on Mars are billions of years old.
The false colour on the image shows that the landslide occurred very recently. Unlike the surrounding terrain, it hasn't be covered by the dust that coats everything on Mars. This makes the reflectiveness, or albedo, different from the regions around it. Scientists think a recent Marsquake or another tiny meteor impact could have triggered the slide.
Original Source: HiRISE News Release
Two spacecraft will Image Venus Together
NASA's MESSENGER and ESA's Venus Express spacecraft are going to be at Venus together on June 6, giving scientists an opportunity to see our "evil" twin planet from two vantage points.
Of course, Venus Express has been orbiting its namesake planet since April 11, 2006, but Messenger is passing through, enroute to Mercury. And that's not all. Several ground-based observatories will be joining in on the party as well, taking images and gathering data during the MESSENGER flyby.
During its closest approach, MESSENGER will pass just 337 kilometres (210 miles) above the surface of Venus. And during this time, Venus Express will be behind Venus, but will be able to view many of the same regions imaged by MESSENGER. Scientists will then be able to compare the data gathered by the two spacecraft.
After 30 hours of observations, MESSENGER will be finished with Venus, and focused again on its final target. It'll finally reach Mercury in March, 2011.
Original Source: ESA News Release
Astrosphere for June 4, 2007
Before I reveal the new stories I discovered on the astro-blogo-sphere, I wanted to remind you about the "The Universe", on the The History Channel. The second episode, Mars: The Red Planet airs on Tuesday at 9:00pm. Check your local listings. You can find out more at history.com/universe
Now, let's see what's happening out there... way out there.
Vern's Weblog has some suggestions for what to see in the night sky this week.
Centauri Dreams puts Alpha Centauri in context.
Personal Spaceflight has some information about Armadillo Aerospace's plans to win the Lunar Lander Challenge.
Becky Ramotowski wants you to mark your calendars, to capture images of the Moon, Venus and Saturn all together.
Now this is hilarious. The Bad Astronomer is reporting that Lisa Nowak (you know... diapers... astronaut) is getting a NASA Spaceflight Medal.
Take a virtual trip to the Moon. Alan Boyle has the story.
Learn about Arcturus, a star totally unlike our Sun. Thanks to the Astroprof.
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