Posted on by Fraser Cain

Libya Montes Valley on Mars

ESA’s Mars Express took this photograph of Libya Montes, which is south of the large Isidis Planitia impact basin on Mars. The region contains a 400 km (248 mile) long valley that was carved into the early Martian surface; probably by water when the planet was warm and wet. Scientists estimate that the same amount of water was probably flowing out of the region as middle reaches of the Mississippi river in the US.

These images, taken by the High Resolution Stereo Camera (HRSC) on board ESA’s Mars Express spacecraft, show the region of Libya Montes, south of the Isidis Planitia impact basin on Mars.

The HRSC obtained these images during orbit 922 with a ground resolution of approximately 14.3 metres per pixel at equatorial latitudes near longitude 81 degrees East.

The images show the central reaches of a 400-kilometre long valley that was carved into the surface in early Martian history, approximately 3500 million years ago.

The central parts of the broad valley show traces of an interior valley, documenting the flow of water that once occurred on the surface of the planet during periods of wetter climate.

Determinations of discharge volumes on the basis of high-resolution HRSC derived digital terrain models reveal discharge rates that are comparable to those of the middle reaches of the Mississippi river in the USA.

On the basis of crater-size frequency distributions on the valley floor and surrounding terrain it has been shown that the formation time of the valley amounts to approximately 350 million years.

Measurements of erosion rates suggest that the active phases of valley development are characterised by short periods of intense fluvial activity rather than sustained liquid flow.

Details on valley formation have been published by R. Jaumann (DLR) and colleagues, as an article ‘Constraints on fluvial erosion by measurements of the Mars Express High Resolution Stereo Camera’ in Geophysical Research Letters, 32, L16203, doi:10.1029/2005GL023415).

***image4:right***The colour scenes were derived from the three HRSC colour channels and the nadir channel. The perspective views have been calculated from the digital terrain model derived from the stereo channels.

The 3D anaglyph image was calculated from the nadir and one stereo channel. The black and white high-resolution images were derived from the nadir channel that provides the highest detail of all the channels.

Original Source: ESA Mars Express

Posted on by Fraser Cain

Nearby Clouds of Gas are Stellar Nursaries in the Making

Astronomers from Boston University have carefully mapped the giant gas clouds in our region of the Milky Way, offering clues to the environment that helped create our Solar System. The team used a large radio telescope that captures high frequency radio waves. When viewed at this wavelength, the clouds are far more transparent, and their inner structure is revealed. All of the clouds they’ve studied so far are lumpy, and will eventually be the birthplaces of stars.

A team of astronomers from Boston University’s Institute for Astrophysical Research has produced the clearest map to-date of the giant gas clouds in the Milky Way that serve as the birthplaces of stars. Using a powerful telescope, the astronomers tracked emissions of a rare form of carbon monoxide called 13CO to chart a portion of our home galaxy and its star-forming molecular clouds.

The researchers hope the new illustration will aid in the identification of additional clouds and study of their internal structure to better understand the origin of stars like the sun, which began its life in such a cloud about 5 billion years ago. The data and images are published in the March issue of the Astrophysical Journal Supplement.

The eight-year project, called the Boston University-Five College Radio Astronomy Observatory (FCRAO) Galactic Ring Survey (GRS), was led by a team of astronomers based at BU, the University of Cologne in Germany, and the University of Massachusetts.

To produce the detailed image, the astronomers mapped the location of 13CO in the Milky Way using a large radio telescope operated by the FCRAO of the University of Massachusetts that captures and images radio emissions at a frequency near 100,000 MHz – about 1,000 times higher than FM stations. When viewed in the emission from 13CO, the clouds are far more transparent than the more traditionally studied 12CO which allowed the team to peer more deeply into their interior.

“The value of such high range imaging is that it enables us to identify the underlying patterns of gas distribution and speeds that point toward the key physical processes occurring within the molecular gas phase of the interstellar medium,” said Dr. Mark Heyer, a researcher from UMass involved in the project.

Using a new receiver developed at UMass, the astronomers could depict the structure of the clouds faster and with much finer detail than any previous attempts. As an added benefit, the distribution of the clouds also delineates the spiral structure of the Milky Way.

“Ironically, because we live inside the Milky Way, we know more about the shapes of far more distant galaxies better than our own,” said James Jackson, astronomy professor at BU and lead investigator of the study. “The GRS map helps us better understand the configuration of our home galaxy and its components.”

“Upon seeing the GRS image, I knew right away it was something terrific. It was like the first time I put on glasses as a kid, and wondered how I ever got along without knowing about every shape, contour and detail of the world around me,” said Dr. Ronak Shah, a researcher from BU who worked on the project. “The GRS has that affect on a lot of us. We thought we understood the Milky Way and then the GRS revealed so much more detail to explore.”

According to Dr. Robert Simon, now at the University of Cologne, but who started the project with Jackson in 1998 at BU, the information from the GRS will constitute an important new database for the study of molecular clouds and Milky Way structure for generations of astronomers.

The scientists are now closely analyzing the image and one of the initial findings is the probable identification of dark, cold molecular clouds in the earliest stages of star development.

“Data from the Galactic Ring Survey have shown that these clouds are the counterparts to active, bright star-forming clouds, but because they have not yet been heated by the embedded stars, they are much colder and quieter,” said Jackson. “Follow-up studies of these clouds will provide additional important clues about the origin of stars since we’ll be able to examine them at an earlier point in their life.”

Another interesting result is that all of the molecular clouds studied so far have similar lumpy structures, regardless of their size, mass, and star-forming activity. These lumps will eventually become stars and, according to the researchers, this similarity suggests that all clouds form stars of various masses in roughly the same proportion.

The Milky Way is a vast disk of 100 billion stars, gas, and dust and because it is flat, the map is long and narrow. Since most of the Galaxy lies in the southern skies, unreachable from Northern Hemisphere telescopes, and because many of the molecular gas clouds are concentrated toward its inner regions, only a portion was imaged.

The Institute for Astrophysical Research (IAR) was founded in 1998 in order to promote and facilitate research and education in astrophysics at Boston University. The IAR supports research by BU Astronomy faculty members, graduate and undergraduate students, and postdoctoral and senior research associates. In addition, the IAR manages and coordinates the use of astrophysical research facilities and promotes the design, development, and operation of instruments and telescopes for astronomical research.

Founded in 1839, Boston University is an internationally recognized institution of higher education and research. With more than 30,000 students, it is the fourth largest independent university in the United States. BU contains 17 colleges and schools along with a number of multi-disciplinary centers and institutes which are central to the school’s research and teaching mission.

Original Source: Boston University

Posted on by Fraser Cain

Dawn Returns from Cancellation

An artist’s illustration of Dawn spacecraft. Image credit: NASA Click to enlarge
Until last week, prospects for the Dawn mission looked bleak. This is a mission designed to send a spacecraft to visit two of the largest asteroids in the Solar System: Ceres and Vesta. The mission had been cancelled on March 2nd, citing technical problems and cost overruns. But NASA managers announced today that Dawn has been reinstated. The project team was able to convince the review board that the technical issues can be solved. The projected launch date has been pushed back a year, however, to July 2007.

NASA senior management announced a decision Monday to reinstate the Dawn mission, a robotic exploration of two major asteroids. Dawn had been canceled because of technical problems and cost overruns.

The mission, named because it was designed to study objects dating from the dawn of the solar system, would travel to Vesta and Ceres, two of the largest asteroids orbiting the sun between Mars and Jupiter. Dawn will use an electric ion propulsion system and orbit multiple objects.

The mission originally was approved in December 2001 and was set for launch in June 2006. Technical problems and other difficulties delayed the projected launch date to July 2007 and pushed the cost from its original estimate of $373 million to $446 million. The decision to cancel Dawn was made March 2, 2006, after about $257 million already had been spent. An additional expenditure of about $14 million would have been required to terminate the project.

The reinstatement resulted from a review process that is part of new management procedures established by NASA Administrator Michael Griffin. The process is intended to help ensure open debate and thorough evaluation of major decisions regarding space exploration and agency operations.

“We revisited a number of technical and financial challenges and the work being done to address them,” said NASA Associate Administrator Rex Geveden, who chaired the review panel. “Our review determined the project team has made substantive progress on many of this mission’s technical issues, and, in the end, we have confidence the mission will succeed.”

The Dawn decision document will be available on the Web at: http://www.nasa.gov/formedia

Original Source: NASA News Release

Posted on by Fraser Cain

What’s Up This Week – March 27 – April 2, 2006

What's Up 2006

Download our free “What’s Up 2006” ebook, with entries like this for every day of the year.

110 Messier Objets. Image credit: Hartmut Frommert – SEDS. Click to enlarge.
Greetings, fellow SkyWatchers! It’s that time of year again … Are you ready to run the Messier Marathon? If you’d rather take your stars at a more leisurely pace – then follow along as we spread 110 of the best sky objects out over the next week. Let’s hope for clear skies as we grab binoculars or telescopes and head out into the night, because…

Here’s what’s up!

Monday, March 27 – This is going to be one incredibly busy week as we start off the show with an occultation of Uranus by the Moon. Check with IOTA for more details.

As we open our week long tour known as a “Messier Marathon,” the late rise of the Moon tonight will be on the side of observers.

Beginning as soon as the sky darkens enough to find the guidestar Delta Cetus, the M77 spiral galaxy will be your first, and the M74 spiral galaxy east of Eta Pisces will be your second mark. Both of these galaxies are telescopic only and will be an extreme challenge at this time of year due to their low position. Even computer-assisted scopes will have some difficulty revealing this pair under less than optimal conditions. Next up is M33 west of Alpha Triangulum. With ideal skies, the “Pinwheel Galaxy” could be seen in binoculars, but skybright will make this huge, low surface brightness spiral difficult for even telescopes at low power. M31 – the Andromeda Galaxy – will, however, be a delightful capture for both binoculars and scopes just west of Nu Andromedae. For the telescope, two more on the list are companions to M31 – the elliptical M32 on the southeastern edge and M110 to the northwest.

Let’s head northwest as we take on two open clusters visible to both telescopes and binoculars. You can find M52 easiest by identifying Alpha and Beta Cassiopeia, drawing a mental line between them and extending it the same distance northwest of Beta. Next just hop north of Delta to pick up our ninth object – the M103 open cluster. Time to head south towards Perseus and go back to the telescope to locate M76, the “Little Dumbbell” planetary nebula, just north of Phi. Binoculars are all that’s needed to see the M34 open cluster also in Perseus, located roughly halfway between the “Demon Star” Algol and lovely double Almach, Gamma Andromeda.

Now that skies are dark and the fastest setting objects are out of the way, we can take a moment to breathe as we view M45 – the Pleiades. The “Seven Sisters” are easily visible to the unaided eye high in the west and their cool, blue beauty is incomparable in binoculars or telescopes. Our next “hop” is with the “rabbit” Lepus as we go back to the south and identify Beta and Epsilon. Triangulating with this pair to the south is a nearly fifth magnitude star (ADS 3954) which will help you locate the small globular M79 to its northeast. At around magnitude 8.5, it is possible to see its very tiny form in binoculars, but M42 – the “Great Orion Nebula” is much easier. The next object, M43, is part of the Orion Nebula, and you will catch it as a small “patch” to the north-northeast. The next two objects, M78 northeast of Zeta Orionis and the M1 Crab Nebula northwest of Zeta Tauri, are both achievable in binoculars with excellent conditions, but are far more interesting to the telescope.

Now we can really relax. Take a few minutes and grab a cup of coffee or hot chocolate and get warmed up. The remaining objects on our observing list for tonight are all very easy, very well positioned for early evening, and all observable in just binoculars. Are you ready? Then let’s go.

M35 is just as simple as finding the “toe” of Gemini – bright Eta. A short hop to the northwest will capture this fine open cluster. The next stop is Auriga and we’ll go directly between silicon star Theta and southern Beta. About halfway between them and slightly to the east you will find open cluster M37. This time let’s use Theta and Iota to its west. Roughly halfway between them and in the center of Auriga you will find M38 and a short hop southeast will capture M36. Now let’s get Sirius and finish this list for tonight. The open cluster M41 in Canis Major is found just as quickly as drifting south of the brightest star in the sky. The last three for tonight couldn’t be any easier – because we just studied them before. Go capture M93, M47 and M46 in Puppis… And give yourself a well-deserved pat on the back.

You’ve just conquered 24 Messiers.

Tuesday, March 28 – Ready for tonight’s challenge? Then nap away the very early evening hours and let’s head out well before bedtime to work on the next section of our week-long “marathon.”

First up will be four binocular targets, the incredibly colorful open cluster M50 is roughly a third of the way in a line drawn between Sirius and Procyon – use binoculars. Hydra is a difficult constellation, but try dropping south-southeast of the most eastern star in Monoceros – Zeta – about half a fist’s width to discover relatively dim open cluster M48. Far brighter, and usually visible to the unaided eye is M44, better known as the Beehive Cluster, just a scant few degrees north-northwest of Delta Cancri. From Delta, go south and identify Alpha because M67 is just to its west. It will appear as a “fine haze” to binoculars, but telescopes will find a spectacular “cloud” of similar magnitude resolvable stars.

Now we really do have to use the telescope again because we’re going “lion taming” by hunting galaxies in Leo. Let’s trade one Alpha for another as we head west to Regulus. Roughly about a fist width east of this major star you will see two dim stars that may require the use of the finderscope – 52 to the north and 53 to the south. We’re heading right between them. About a degree and a half south of 52, you will discover ninth magnitude elliptical M105. Larger scopes will also show two additional faint galaxies, NGC 3384 and NGC 3389 to M105’s west. Continuing about a degree south towards star 53 you will spot the silver-gray beauty of M96 in a relatively starless field. Enjoy its bright nucleus and wispy arms.

About another degree west will bring you to M95, which is neither as bright nor as large as its Messier “neighbor.” Small scopes should show a brightening towards its center and large ones should begin to resolve out the arms of this awesome barred spiral. Our next destination is the southwestern star of the three that mark Leo’s “hips,” Theta Leonis – or more commonly called Chort. South of it you will see faint star 73 and right around one degree to its east-southeast you will locate a pair. In small scopes at low power, M65 and M66 are same field. The western M65 and eastern M66 are both beautiful spirals.

Now let’s head north for another “same field pair” of galaxies and hunt down M81 and M82 in Ursa Major. Many folks have trouble “star hopping” to these galaxies, but a very simple way of finding them is to draw a mental line between Phecda (Gamma) and Dubhe (Alpha). By extending that line beyond Dubhe almost the same distance, you’ll locate our next two “marathon” objects. At low power with a smaller scope, the southern-most and most pronounced of the two is the stunning M81 with its bright core. To the north is broken, spindle-shaped peculiar galaxy M82. Viewable in binoculars, we’ll study more about this pair later on as we head for Mirak (Beta) and our next galaxy. About a degree and a half southeast you will see a 10th magnitude “scratch” of light. This great edge-on galaxy – M108 – should show at least four brighter “patches” to the small scope and a nice dark dust-lane to larger ones. Continuing about another half degree southeast will bring you to the planetary nebula M97. Also known as the “Owl,” this 12th magnitude beauty is roughly the same diameter as Jupiter and can be spotted under optimal conditions with binoculars – but requires a large scope at high power to begin to discern its features. Let’s continue south to Phecda and less than half a degree to the east you will locate M109. In the field with Gamma, M109 will show its faded central bar and prominent nucleus to the small scope, but requires large aperture and high magnification to make out structure. The last in Ursa Major is an error on Messier’s part. Labeled as M40, this object is actually double star WNC 4, located in the same eyepiece field as 70 Ursae Majoris to the northeast.

Now let’s move into Canes Venatici and round up a few more. This is an area of dimmer stars, but the two major stars, Alpha (it is called Cor Caroli and it is a wonderful double star) and Beta are easily recognizable to the east of the last star in the “handle” of the “Big Dipper” (Eta). The northernmost is Beta and you will find the soft-spoken spiral galaxy M106 almost midway between it and Phecda less than 2 degrees south of star 3. M94 is a much brighter, compact galaxy and is found by forming an isosceles triangle with Alpha and Beta Canum with the imaginary apex towards Eta Ursae Majoris. M63 is a very pretty, bright galaxy (often known as “the Sunflower”) that approaches magnitude 10 and is found about one-third the distance between Cor Caroli and Eta Ursae Majoris (Alkaid). Still heading towards Alkaid (Eta UM), the incomparable M51 comes next. Near Eta you will see an unmistakable visual star called 24 CnV, the “Whirlpool” is the same basic distance to the southwest. Now that we’re back into “big bear country” again, we might as well head on to the M101 “Pinwheel” galaxy which is found by following the same trajectory and distance to the other side of Alkaid. Before we head on, let’s continue north and clean up… ummm… another “messy mistake.” The accepted designation for M102 is lenticular galaxy NGC 5866, located in Draco south east of Iota.

Now let’s finish up – it’s getting late. Our next stop will be to identify the three primary stars of Coma Berenices now high in the east above Arcturus. You will find small globular cluster M53 northeast of Alpha. One of the coolest galaxies around is M64 (known as the “Blackeye”) just a degree east-northeast of 35 Comae, which is about one-third the distance between Alpha Comae and Alkaid. The last, and most outstanding for the night, is a globular cluster that can be seen in binoculars – M3. As strange as this may sound, you can find M3 easily by drawing a line between Cor Caroli and Arcturus. Starting at Arcturus, move up about one third the way until you see Beta Comae to the west of your “line”… Poof. There it is.

Awesome job. We’ve just completed another 24 objects and we’ve claimed 48 on the Messier list before bedtime in two days.

Wednesday, March 29 Born today in 1749, Pierre Laplace was the mathematician who invented the metric system and the nebular hypothesis for the origin of the solar system. Also born on this day in 1693 was James Bradley, an excellent astrometrist who discovered the aberration of starlight in 1729, as well as the nutation of the Earth. In 1802, Heinrich W. Olbers discovered the second asteroid, Pallas, in the constellation Virgo while making observations of the position of Ceres, which had only been discovered fifteen months earlier. Five years later on this same date in 1807, Vesta – the brightest asteroid – was discovered by Olbers in Virgo, making it the fourth such object found.

And if you thought this day was busy in history, then it’s about to get a whole lot busier as we add a total solar eclipse! While the path of totality is quite narrow, viewers across portions of Asia, Europe and North Africa will see the Sun partially eclipsed. Please check Fred Espenak’s Eclipse Home Page for precise times and locations… And check the web for live feeds of the event!

We have one more day until New Moon, but the challenge will not be so much avoiding Luna, or the visibility of the next objects – but the “window of opportunity” in which we’ll be able to see them. Am I going to ask you to stay up past your bedtime? Darn right…

These next targets will be best viewed after midnight when the constellations of Coma Berenices and Virgo have well risen, providing us with the darkest sky and best position. For the large telescope, we are going to be walking into an incredibly rich galaxy field that we will touch on only briefly because they will become the object of future studies. Just keep in mind that our Messier objects are by far the brightest of the many you will see in the field. For the smaller scope? Don’t despair. These are quite easy enough for you to see as well and probably far less confusing because there won’t be so many of them visible. Now let’s identify the easternmost star in Leo – Denebola – and head about a fist width due East…

Our first will be M98, just west of star 6 Comae. It will be a nice edge-on spiral galaxy in Coma Berenices. Next return to 6 Comae and go one degree southeast to capture M99, a face-on spiral known as the “Pinwheel” that can be seen in apertures as small as 4″. Return to 6 Comae and head two degrees northeast. You will pass two fifth magnitude stars that point the way to M100 – the largest appearing galaxy in the Coma/Virgo cluster. To the average scope, it will look like a dim globular cluster with a stellar nucleus. Now let’s continue on two degrees north where you will see bright yellow 11 Comae. One degree northeast is all it takes to catch the ninth magnitude, round M85. (Ignore that barred spiral. let’s keep moving…) Now, let’s try a “trick of the trade” to locate two more. Going back to 6 Comae, relocate M99 and turn off your drive. If you are accurately aligned to the equator, you may now take a break for 14 minutes. When you return the elongated form and near stellar nucleus of M88 will have “drifted” into view. Wait another two to three minutes and the faint barred spiral M91 will have joined the show in a one degree field of view? Pretty fun, huh?

Now let’s shift guidestars by locating bright Vindemiatrix (Epsilon Virginis) almost due east of Denebola. Let’s hop four and a half degrees west and a shade north of Epsilon to locate one of the largest elliptical galaxies presently known – M60. At a little brighter than magnitude 9, this galaxy could be spotted with binoculars. In the same telescopic low power field you will also note faint NGC 4647 which only appears to be interacting with M60. Also in the field is our next Messier, bright cored elliptical M59 to the west. (Yes, there’s more – but not tonight.) Moving a degree west of this group will bring you to our “galactic twin,” fainter M58. Moving about a degree north will call up face-on spiral M89, which will show a nice core region in most scopes. One half degree northeast is where you will find the delightful 9.5 magnitude M90 – whose dark dust lanes will show to larger scopes. Continue on one and a half degrees southwest for M87, one of the first radio sources discovered. This particular galaxy has shown evidence of containing a black hole and its elliptical form is surrounded by more than 4,000 globular clusters.

Just slightly more than a degree northwest is a same field pair, M84 and M86. Although large aperture scopes will see many more in the field, concentrate on the two bright cored ellipticals which are almost identical. M84 will drift out of the field first to the west and M86 is east. Next we will select a new guidestar by going to 31 Virginis to identify splendid variable R about a degree to its west. We then move two degrees northwest of R to gather in the evenly lighted oval of M49. Now shifting about three degrees southwest, you will see a handsome yellow double – 17 Virginis. Only one-half degree south is the large face-on spiral, M61. Larger scopes will see arms and dust lanes in this one. Last for tonight is to head for the bright blue beauty of Spica and go just slightly more than a fist width (11 degrees) due west. M104 – the “Sombrero” galaxy – will be your reward for a job well done.

Congratulations. You’ve just seen 17 of the finest galaxies in the Coma/Virgo region and our “Marathon” total for three days has now reached 65. We’re over halfway home…

Thursday, March 30 – Today celebrates the first flyby of Mercury by Mariner 10 in 1974.

Hey… It’s New Moon. While tonight would be the “perfect choice” for completing a Messier Marathon from start to finish, there are no iron-clad guarantees that the sky will cooperate on this date. Even worse? Many of us have to work the next day. So what’s an astronomer to do, eh? How about if we try an “early to bed and early to rise” attitude and conquer these next objects well ahead of the dawn? Set your alarm for 3:00 am, dress warm and let’s dance.

With Corvus relatively high to the south, the drop is about five degrees to the south-south east of Beta Corvi. Just visible to the unaided eye will be the marker star – the double A8612. Eighth magnitude M68 is a bright, compact globular cluster in Hydra that will appear as a “fuzzy star” to binoculars and a treat to the telescope. Our next is tough for far-northern observers, for the “Southern Pinwheel” – M83 – is close to ten degrees southeast of Gamma Hydrae. (This is why it is imperative to get up early enough to catch this constellation at its highest.)

Now we’re going to make a wide move across the sky and head southeast of brilliant Arcturus for Alpha Serpentis. About 8 degrees southwest you will find outstanding globular cluster M5 sharing the field with 5 Serpens. Now locate the “keystone” shape of Hercules and identify Eta in its northwest corner. About one-third of the way between it and Zeta to the south is the fantastic M13, also known as the “Great Hercules Globular Cluster.” A little more difficult to find is the small M92 because there are no stars to guide you. Try this trick – Using the two northernmost stars in the “keystone,” form an equilateral triangle in your mind with its imaginary apex to the north. Point your scope there. At sixth magnitude, this compact globular cluster has a distinct nucleus.

Now we’re off to enjoy summer favorites and future studies. M57, the “Ring Nebula,” is located about halfway between Sheilak and Sulafat. You’ll find the small globular M56 residing conveniently about midpoint between Sulafat and Alberio. About 2 degrees south of Gamma Cygni is the bright open cluster M29. And equally bright M39 lays a little less than a fist width to the northeast of Deneb. If you remember our hop north of Gamma Sagitta, you’ll easily find M27, the “Dumbbell Nebula,” and the loose globular, M71, just southwest of Gamma. All of the objects in this last paragraph are viewable with binoculars (albeit some are quite small) and all are spectacular in the telescope.

And now we’ve made it to 76 on our “Messier Hit List.”

Friday, March 31 – So, are you having fun yet? Now we’re moving into early morning skies and looking at our own galactic halo as we track down some great globular clusters. What time of day, do you ask? Roughly two hours before dawn…

Ophiuchus is a sprawling constellation and its many stars can sometimes be hard to identify. Let’s start first with Beta Scorpii (Graffias) and head about a fist’s width to the northeast. That’s Zeta and the marker you will need to locate M107. About one quarter the way back towards Graffias, you will see a line of three stars in the finder. Aim at the center one and you’ll find this globular in the same field. Now go back to Zeta and you will see a pair of similar magnitude dim stars higher to the northeast. The southernmost is star 30 and you will find the M10 globular cluster about one degree to its west. M12 is only about three degrees further along to the northeast. Both are wonderfully large and bright enough to be seen in binoculars.

Now we need to identify Alpha in Ophiuchus. Head toward Hercules. South of the “keystone” you will see bright Beta Hercules with Alpha Hercules to the southeast. The next bright star along the line is Alpha Ophiuchi and globular cluster M14 is approximately 16 degrees south and pretty much due east of M10. Now let’s head for bright Eta Ophiuchi (Sabik) directly between Scorpius and Sagittarius. The next globular, M9, is about three and a half degrees southeast.

Now let’s move on to an easier one. All you need to know is Antares to find the globular cluster M4 in Scorpius. All you have to do is aim your binoculars there, for this diffuse giant is just a little over one degree to the west. Go back to Antares and shift about four degrees to the northwest and you’ll find compact, bright globular M80. It will be very small in binoculars, but it’s quite bright. Going back to the scope is best for M19, although it’s easy to find around seven degrees due east of Antares. The last for this morning is M62 about a half a fist’s width to the south.

Hey, you’re doing terrific. Some of these are tough to find unless you’ve had practice… But now we’re up to a total of 85.

Saturday, April 1 – Today in 1960, the first weather satellite – Tiros 1 – was launched. Let’s hope our weather holds as we complete our week long Messier Marathon!

Ready to get up early again? I know it’s hard, but what we’re after this morning is truly worth it. These are some of the most beautiful objects in the sky.

The lower curve of Scorpius is quite distinctive and the unaided eye pair you see at the “stinger” is beautiful double Shaula (Lambda) and its slightly less bright neighbor Upsilon. Aim your binoculars there and head towards the northeast and you cannot miss M6, the “Butterfly Cluster.” Below it and slightly east is a hazy patch, aim there and you will find another spectacular open cluster M7, often known as “Ptolemy’s Cluster.”

Now go north and identify Lambda Aquilae and you will find M11, the “Wild Duck” open cluster just to the west. About the same distance away to the south/southwest you will spot M26, another open cluster. These are all great binocular targets, but it will take an exceptionally dark, clear sky to see the Eagle Nebula associated with the M16 easy open cluster about a fist’s width away to the southwest. Far easier to see is the “Nike Swoosh” of M17 just a little further south. Many of you know this as the “Omega” or “Swan” nebula. Keeping moving south and you will see a very small collection of stars known as M18, and a bit more south will bring up a huge cloud of stars called M24. This patch of Milky Way “stuff” will show a wonderful open cluster – NGC 6603 – to average telescopes and some great Barnard darks to larger ones.

Now we’re going to shift to the southeast just a shade and pick up the M25 open cluster and head due west about a fist’s width to capture the next open cluster – M23. From there, we are dropping south again and M21 will be your reward. Head back for your scope and remember your area, because the M20 “Triffid Nebula” is just a shade to the southwest. Small scopes will pick up on the little glowing ball, but anything from about 4″ up can see those dark dust lanes that make this nebula so special. You can go back to the binoculars again, because the M8 “Lagoon Nebula” is south again and very easy to see.

This particular star hop is very fun. If you have children who would like to see some of these riches, point out the primary stars and show them how it looks like a dot-to-dot “tea kettle.” From the kettle’s “spout” pours the “steam” of the Milky Way. If you start there, all you will need to do is follow the “steam” trail up the sky and you can see the majority of these with ease.

Our Messier total has now risen to 98…

Sunday, April 2 – OK, folks… It’s “crunch time” and the first few on this list will be fairly easy before dawn, but you won’t have long before the light steals the last few from the sky.

At the top of the “tea kettle” is Lambda. This is our marker for two easy binocular objects. The small M28 globular cluster is quite easily found just a breath to the north/northwest. The larger, brighter and quite wonderful globular cluster M22 is also very easily found to Lambda’s northeast. Now we’re roaming into “binocular possible” but better with the telescope objects. The southeastern corner of the “tea kettle” is Zeta, and we’re going to hop across the bottom to the west. Starting at Zeta, slide southwest to capture globular cluster M54. Keep heading another three degrees southwest and you will see the fuzzy ball of M70. Just around two degrees more to the west is another globular that looks like M70’s twin. Say good morning to M69.

Now it’s really going to get tough. The small globular M55 is out there in “No Man’s Land” about a fist’s width away east/south east of Zeta and the dawn is coming. It’s going to be even harder to find the equally small globular M75, but if you can see Beta Capricorn it will be about a fist’s width southwest. Look for a “V” pattern of stars in the finder and go to the northeastern star of this trio. You should be able to put it in the same low power field. Without the “square” of Pegasus to guide us, look low to the east and identify Enif by its reddish color. (Delphinus above it should help you.) Power punch globular M15 is to Enif’s northwest and you should be able to see the star on its border in the finderscope. Let’s be thankful that M2 is such a fine, large globular cluster. The hop is two thirds of the way between Enif and Beta Aquarius, or just a little less than a fist’s width due west of Alpha.

Let’s hope that Beta is still shining bright, because we’ll need to head about a fist’s width away again to the southwest to snag what will now be two very dim ones – the M72 globular cluster and M73 open cluster just west of Nu Aquarius. We’re now running just ahead of the light of dawn and the M30 globular cluster is our last object. Hang on Delta Capricornus and show us the way south/southwest to star 41. If you can find that? You’ve got the very last one…

We’ve done the Messier Catalog of all 110 objects in just one week!

Is this a perfect list with perfect instructions? No way. Just like the sky, things aren’t always perfect. This is just a general guideline to helping you find the Messier objects for yourself. Unless you are using a computer-guided scope, it truly takes a lot of practice to find all the Messiers with ease, so don’t be discouraged if they just don’t fall from the sky. You might find all of these in one year or one week – and you just might find all of them in one good night. Regardless of how long it takes you – or when the skies cooperate – the beauty, joy and reward is the peace and pleasure it brings.

Today in 1889, the Harvard Observatory’s 13″ refractor arrived at Mt. Wilson. Just one month later, it began a long astronomical legacy at Lick Observatory. It was here that the largest telescopes in the world resided from 1908 to 1948. The 60″ for the first decade, and followed by the 100″. This latter mirror is still the largest solid piece ever cast in plate glass and weighed 4 1/2 tons. Would you believe it’s just 13 inches thick?

Thankfully we’d didn’t need it for our marathon!

Today in 1845, the first photograph of the Sun was taken. While solar photography and observing is best left to properly filtered telescopes, no special equipment is necessary to see some effects of the Sun – only the correct conditions. We’ll find out why tomorrow night…

Tonight let’s take it easy after our marathon and relax as we take a look at lunar features. Begin by identifying Mare Crisium and shallow crater Cleomides to its north. About twice its width northwest, you will see a sharply well-defined Class I crater Geminus. Named for the Greek astronomer and mathematician Geminos, this 86 kilometer wide crater shows a smooth floor and displays a long, low dune across its middle.

May all your journeys be at light speed… ~Tammy Plotner.

Posted on by Fraser Cain

Astrophoto: The Veil Nebula Complex by Johannes Schedler

The Vela Nebula Complex by Johannes Schedler
Floating like a vast, thin wreath on a sea filled with colorful, bright stars, these wisps and tendrils are all that’s left to mark the ancient resting place of an exploded sun. The star detonated in a flash of light that would have rivaled the full moon in the sky. The accompanying thumbnail image is just a small part of a much larger collection of structures that, combined, form a unique northern night sky object known as the Veil Nebula Complex.

Located in the constellation of Cygnus, the Veil Nebula Complex floats approximately 1,400 light years from our home planet; the remains of a supernova event that took place in pre-history, between 5,000 and 10,000 years ago. It’s estimated that the light from this explosion was visible in the night sky for several months and easily cast shadows on the ground for over a week after it initially detonated. Over time, the energy and material that was ejected into the inter-stellar medium has now expanded until it covers an area over six times the diameter of the full moon.

This spectacular image is particularly unique in that the colors displayed are not natural- they have been scientifically enhanced through the use of filters and special image processing. For example, the red coloration indicates areas of the nebula where hydrogen gas is plentiful and has been excited into radiating a crimson color. The blue and green areas represent places where enormous amounts of molecular oxygen are the primary nebula constituent. This picture is a good example of the way science uses light and hue to understand the makeup of the cosmos through the use of special filters that only transmit the glow of specific elements. By assigning unique colors to each element, a map of its component distribution can be created, thus this process is also known as mapped coloring.

Johannes Schedler produce this picture, actually a mosaic of six separate images seamlessly stitched together, from his backyard observatory located in Wildon, a small town near the city of Graz, in south-eastern Austria. The pictures were taken through a 16-inch (410mm) telescope operating at f/3. For each of the six images used in this huge sky panorama, Johannes gathered the ancient light for over three and a half hours with a CCD camera. In total, the entire mosaic represents a twenty-two hour exposure!

Do you have photos you’d like to share? Post them to the Universe Today astrophotography forum or email them, and we might feature one in Universe Today.

Written by R. Jay GaBany

Posted on by Fraser Cain

SpaceX Rocket Launch Fails

The maiden voyage of SpaceX’s Falcon 1 rocket started well, but then went sour moments after launch. Onboard cameras, broadcast live to the Internet showed the rocket rolling almost immediately and then the connection was cut. Company founder, Elon Musk, later commented that Falcon 1 managed about 1 minute of powered flight. The rocket was carrying a small satellite for the US Air Force called FalconSat-2, which would have investigated space weather.

Posted on by Fraser Cain

Microscopic Tunnels Carved by Martian Microbes?

A thin slice of the Nakhla meteor. Image credit: OSU Click to enlarge.
Bacteria seem to live anywhere there’s water. One class of bacteria are known to burrow through igneous rock feeding on iron and other chemicals, and leaving a tiny tunnel behind them. Now researchers have found similar tunnels in a meteorite believed to have originated on Mars called the Nakhla meteorite. This adds additional data to the mounting evidence that Mars was wet in the distant past, and gives the tantalizing possibility that it was inhabited with life.

A new study of a meteorite that originated from Mars has revealed a series of microscopic tunnels that are similar in size, shape and distribution to tracks left on Earth rocks by feeding bacteria.

And though researchers were unable to extract DNA from the Martian rocks, the finding nonetheless adds intrigue to the search for life beyond Earth.

Results of the study were published in the latest edition of the journal Astrobiology.

Martin Fisk, a professor of marine geology in the College of Oceanic and Atmospheric Sciences at Oregon State University and lead author of the study, said the discovery of the tiny burrows do not confirm that there is life on Mars, nor does the lack of DNA from the meteorite discount the possibility.

“Virtually all of the tunnel marks on Earth rocks that we have examined were the result of bacterial invasion,” Fisk said. “In every instance, we’ve been able to extract DNA from these Earth rocks, but we have not yet been able to do that with the Martian samples.

“There are two possible explanations,” he added. “One is that there is an abiotic way to create those tunnels in rock on Earth, and we just haven’t found it yet. The second possibility is that the tunnels on Martian rocks are indeed biological in nature, but the conditions are such on Mars that the DNA was not preserved.”

More than 30 meteorites that originated on Mars have been identified. These rocks from Mars have a unique chemical signature based on the gases trapped within. These rocks were “blasted off” the planet when Mars was struck by asteroids or comets and eventually these Martian meteorites crossed Earth’s orbit and plummeted to the ground.

One of these is Nakhla, which landed in Egypt in 1911, and provided the source material for Fisk’s study. Scientists have dated the igneous rock fragment from Nakhla – which weighs about 20 pounds – at 1.3 billion years in age. They believe that the rock was exposed to water about 600 million years ago, based on the age of clay found inside the rocks.

“It is commonly believed that water is a necessary ingredient for life,” Fisk said, “so if bacteria laid down the tunnels in the rock when the rock was wet, they may have died 600 million years ago. That may explain why we can’t find DNA – it is an organic compound that can break down.”

Other authors on the paper include Olivia Mason, an OSU graduate student; Radu Popa, of Portland State University; Michael Storrie-Lombardi, of the Kinohi Institute in Pasadena, Calif.; and Edward Vicenci, from the Smithsonian Institution.

Fisk and his colleagues have spent much of the past 15 years studying microbes that can break down igneous rock and live in the obsidian-like volcanic glass. They first identified the bacteria through their signature tunnels then were able to extract DNA from the rock samples – which have been found in such diverse environments on Earth as below the ocean floor, in deserts and on dry mountaintops.

They even found bacteria 4,000 feet below the surface in Hawaii that they reached by drilling through solid rock.

In all of these Earth rock samples that contain tunnels, the biological activity began at a fracture in the rock or the edge of a mineral where the water was present. Igneous rocks are initially sterile because they erupt at temperatures exceeding 1,000 degrees C. – and life cannot establish itself until the rocks cool. Bacteria may be introduced into the rock via dust or water, Fisk pointed out.

“Several types of bacteria are capable of using the chemical energy of rocks as a food source,” he said. “One group of bacteria in particular is capable of getting all of its energy from chemicals alone, and one of the elements they use is iron – which typically comprises 5 to 10 percent of volcanic rock.”

Another group of OSU researchers, led by microbiologist Stephen Giovannoni, has collected rocks from the deep ocean and begun developing cultures to see if they can replicate the rock-eating bacteria. Similar environments usually produce similar strains of bacteria, Fisk said, with variable factors including temperature, pH levels, salt levels, and the presence of oxygen.

The igneous rocks from Mars are similar to many of those found on Earth, and virtually identical to those found in a handful of environments, including a volcanic field found in Canada.

One question the OSU researchers hope to answer is whether the bacteria begin devouring the rock as soon as they are introduced. Such a discovery would help them estimate when water – and possibly life – may have been introduced on Mars.

Original Source: OSU News Release

Posted on by Fraser Cain

A Nearby Twin of the Sun

HD98618 would look almost identical to our Sun. Image credit: SOHO Click to enlarge.
When astronomers start searching for evidence of live orbiting other stars, they’ll start with familiar terrain: other stars like our Sun. Astronomers from the Australian National University have identified a nearby candidate that’s a virtual twin of our Sun in age, size, temperature and chemistry; although, it’s 2% more massive. The star, HD98618, is located 126 light-years away in the constellation Ursa Major (the Big Dipper), and is bright enough to see with binoculars.

ANU astronomers have discovered a nearby solar twin which may shed light on the search for planets that are similar to Earth and that may even support life.

HD98618 is only the second star found so far that is almost identical to the Sun in age, size, temperature and chemistry, according to the researchers Dr Jorge Meléndez, Ms Katie Dodds-Eden and Mr José Robles, from the Research School of Astronomy and Astrophysics.

“This solar twin doesn’t only have the same mass as the Sun, it was also formed with the same ‘chemical recipe’. So this star was equipped in the same way as the Sun to form Earth-like planets,” Mr Robles said.

“Hopefully, as new planet finding techniques are developed and refined, astronomers will find whether HD98618 hosts terrestrial planets, which may even contain life.”

HD98618 lies a mere 126 light-years away in the northern constellation of Ursa Major (the ‘Big Dipper’). It is bright enough to see in binoculars, but only in the Northern Hemisphere.

The researchers believe that HD98618 is about four billion years-old, about 10 per cent younger than our own Sun. Its chemical properties are almost identical to the Sun and to the other closest Sun twin, a star known as 18 Scorpii, which was discovered a decade ago.

“It means that hypothetical terrestrial planets around this solar twin may have had enough time to develop some kind of complex life, assuming the time-scale for complex life formation is similar to Earth’s,” Dr Meléndez said.

The team says that focused observations of the two stars by planet-hunter teams could reveal or rule out within a few years giant planets, such as our own Jupiter, around HD98618. “18 Scorpii and HD98618 offer hope to find solar systems similar to our own in the Universe,” Dr Meléndez said.

The discovery also has implications for research in other areas. Solar twins are ideal for the absolute calibration of astronomical measuring instruments. They can provide data useful in modelling the solar phenomena that may affect climate change, and will help settle the argument about the uniqueness or otherwise of our Sun and Solar System.

“We had a number of candidates with similar properties to the Sun, but while we held out hope for each star that it would turn out to be really special, it was not at all certain to happen. HD 98618 was one of the last of our candidates to be analysed, so it was quite a surprise when we discovered how it stood out from the other candidates, together with 18 Scorpii. It was very exciting – I had to blink twice to be sure I wasn’t imagining it,” Ms Dodds-Eden said.

The researchers made the discovery using the largest telescope in the world, the 10m Keck I telescope on the summit of Hawaii’s dormant Mauna Kea volcano.

Their paper detailing the discovery will be published in Astrophysical Journal Letters. Related images are available from the ANU Media Office.

Original Source: ANU News Release

Posted on by Fraser Cain

First Photo from Mars Reconnaissance Orbiter

A portion of the first full-resolution image returned by MRO. Image credit: NASA/JPL. Click to enlarge.
After years of development and months of spaceflight, NASA’s Mars Reconnaissance Orbiter is beginning to return photos of the Red Planet. The spacecraft pointed three of its cameras at the surface of Mars on Thursday, and started snapping pictures. This photo was taken when the spacecraft was at an altitude of 2,489 kilometers (1,547 miles), which is about 9 times as high as its final orbit – the pictures are going to just get better. Even so, the resolution at this altitude is about the same as the best pictures returned by other Mars orbiters.

The first test images of Mars from NASA’s newest spacecraft provide a tantalizing preview of what the orbiter will reveal when its main science mission begins next fall.

Three cameras on NASA’s Mars Reconnaissance Orbiter were pointed at Mars at 8:36 p.m. PST Thursday, while the spacecraft collected 40 minutes of engineering test data. The cameras are the High Resolution Imaging Science Experiment, the Context Camera and the Mars Color Imager.

“These high-resolution images of Mars are thrilling, and unique given the early morning time-of-day. The final orbit of Mars Reconnaissance Orbiter will be over Mars in the mid-afternoon, like Mars Global Surveyor and Mars Odyssey,” said Alfred McEwen, University of Arizona, Tucson, principal investigator for the orbiter’s High Resolution Imaging Science Experiment camera.

“These images provide the first opportunity to test camera settings and the spacecraft’s ability to point the camera with Mars filling the instruments’ field of view,” said Steve Saunders, the mission’s program scientist at NASA Headquarters. “The information learned will be used to prepare for the primary mission next fall.” The main purpose of these images is to enable the camera team to develop calibration and image-processing procedures such as the precise corrections needed for color imaging and for high-resolution surface measurements from stereo pairs of images.

To get desired groundspeeds and lighting conditions for the test images, researchers programmed the cameras to shoot while the spacecraft was flying about 2,489 kilometers (1,547 miles) or more above Mars’ surface, about nine times the range planned for the orbiter’s primary science mission. Even so, the highest resolution of about 2.5 meters (8 feet) per pixel – an object 8 feet in diameter would appear as a dot — is comparable to some of the best resolution previously achieved from Mars orbit.

Further processing of the images during the next week or two is expected to combine narrow swaths into broader views and show color in some portions.

The Mars Reconnaissance Orbiter has been flying in elongated orbits around Mars since it entered orbit on March 10. Every 35 hours, it has swung about 44,000 kilometers (27,000 miles) away from the planet then come back within about 425 kilometers (264 miles) of Mars’ surface.

Mission operations teams at NASA’s Jet Propulsion Laboratory, Pasadena, Calif, and at Lockheed Martin Space Systems, Denver, continue preparing for aerobraking. That process will use about 550 careful dips into the atmosphere during the next seven months to shrink the orbit to a near-circular shape less than 300 kilometers (200 miles) above the ground.

More than 25 gigabits of imaging data, enough to nearly fill five CD-ROMs, were received through NASA’s Deep Space Network station at Canberra, Australia, and sent to JPL. They were made available to the camera teams at the University of Arizona Lunar and Planetary Laboratory and Malin Space Science Systems, San Diego, Calif.

Preliminary images from the High Resolution Imaging Science Experiment and additional information about the Mars Reconnaissance Orbiter are available online at: http://www.nasa.gov/mro or http://HiRISE.lpl.arizona.edu

Additional processing has begun for release of other images from the test in coming days.

For information about NASA and agency programs on the Web, visit: http://www.nasa.gov

JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter for NASA’s Science Mission Directorate, Washington. Lockheed Martin Space Systems is the prime contractor for the project and built the spacecraft.

Original Source: NASA/JPL News Release

Posted on by Fraser Cain

Quasar Ignition in the Distant Universe

An illustration showing a quasar at the center of the galaxy. Image credit: NASA Click to enlarge
Sometimes the supermassive black holes at the hearts of galaxies are quiet, and nearly invisible. Other times they’re actively gobbling up material, blazing as quasars in the X-ray spectrum. NASA’s Chandra X-Ray Observatory has observed one of these transition times, when the heated material around the supermassive black hole is beginning to ignite. It’s likely the galaxy recently collided or merged with another galaxy, and the turbulence caused material to fall into the black hole.

An artist’s illustration depicts a quasar in the center of a galaxy that has turned on and is expelling gas at high speeds in a galactic superwind. Clouds of hot, X-ray producing gas detected by Chandra around the quasars 4C37.43 and 3C249.1, provide strong evidence for such superwinds.

The X-ray features seen at five, six, ten and eleven o’clock in the 4C37.43 image are located tens of thousands of light years from the central supermassive black hole that powers the quasar. They are likely due to shock waves in the superwind.

Mergers of galaxies are a possible cause for the ignition, or turn-on, of quasars. Computer simulations show that a galactic merger drives gas toward the central region where it triggers a burst of star formation and provides fuel for the growth of a central black hole.

The inflow of gas into the black hole releases tremendous energy, and a quasar is born. The power output of the quasar dwarfs that of the surrounding galaxy and pushes gas out of the galaxy in a galactic superwind.

Over a period of about 100 million years, the superwind will drive most of the gas away from the central regions of the galaxy, quenching both star formation and further supermassive black hole growth. The quasar phase will end and the galaxy will settle down to a relatively quiet life.

Original Source: Chandra X-ray Observatory