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Chandra Gives Another Look at the Pillars of Creation.
Probably the most famous photograph every taken by the Hubble Space Telescope is of the 'Pillars of Creation'; a star forming region inside the Eagle Nebula (aka M16). Astronomers have wanted to know just how much star formation is actually going on inside the nebula.
One of Hubble's co-Great Observatories, the Chandra X-Ray Observatory, has observed the region too, and is helping answer that question. The attached photograph is a composite between the original Hubble photograph overlaid with data from Chandra. The bright multicoloured spots in the photograph are sources of X-rays, such as stars.
If you'll notice, there are plenty of X-ray sources around the photograph, but almost none inside the pillars themselves. What's going on? It's possible that there aren't any stars in there at all, but Infrared observations have found infant stellar objects, including 4 large enough to form stars. Another possibility is that the stars inside the pillars are so young, they haven't gotten to the point that they're generating X-rays yet.
Original Source: http://chandra.harvard.edu/photo/2007/m16/
Spacecraft Finds Evidence of Underground Fluids on Mars
Here's an interesting new result from NASA's Mars Reconnaissance Orbiter. scientists announced today that the spacecraft has turned up evidence that some kind of liquid or gas once flowed beneath the surface of Mars.
This is one of those rare situations where the most beautiful pictures returned from Mars also have some of the most interesting science. If you look at the attached picture to this story, you see the beautiful patterns of exposed layers in a canyon called Candor Chasma.
Geologist Chris Okubo from the University of Arizona, Tuscon explains what he noticed, and what you're looking at:
At some point in the distant past, fluids moved through underground channels. Minerals in the fluid were deposited in layers over the course of millions of years. And then weathering from wind and sand eroded away the material, exposing the layered pattern.
Mars Reconnaissance Orbiter's high resolution imaging made all the difference here - it's capable of revealing details as small as one metre (3 feet). This allows scientists to spot details that go unseen with other spacecraft.
Original Source: NASA/JPL News Release
Atlantis Moves Out to the Launch Pad
The Space Shuttle Atlantis made its journey out to the launch pad on Thursday, perched atop the slow-moving crawler transporter. If everything goes well, Atlantis will blast off on March 15, beginning an 11-day visit to the International Space Station to install a new truss segment.
Before the liftoff, the launch team and astronauts will perform a full launch dress rehearsal from February 21st to the 23rd. This will give everyone involved an opportunity to test out their contingency plans and emergency readiness.
Once Atlantis does launch on the 15th, the crew will help install the new truss segment, retract an old set of solar arrays, and unfurl the the new, larger starboard arrays on the station.
Original Source: NASA News Release
Lunar Eclipse Coming on March 3, 2007
Skywatchers in Eastern North America, Europe, Africa and parts of Asia are about the be treated to one of the most beautiful events in the night sky: a total lunar eclipse. The eclipse gets underway on Saturday, March 3, 2007, and will last about 6 hours from start to finish.
For observers in Eastern North America, the eclipse will already be underway when the Moon rises, but observers East of the Great Lakes should be able to see the Moon completely obscured, and then exist the Earth's shadow as the evening progresses.
If you want to know when to look, the greatest eclipse will occur at 23:20 UT (6:20pm EST).
Original Source: Science@NASA
Hubble View of Planetary Nebula NGC 2440
This beautiful photograph was captured by the Hubble Space Telescope's Wide Field Planetary Camera 2, and it shows the planetary nebula NGC 2440. Once again, we're looking at a haunting vision of the future that awaits our own Sun.
The star at the heart of NGC 2440 cast off its outer layers of gas, creating the cocoon that we see now. The ultraviolet radiation from the star is radiating outward, illuminating the gas, so we can see it through Hubble. Once a main sequence star like our Sun, the central star is now a hot White Dwarf - one of the hottest ever discovered, with a surface temperature of 200,000 degrees Celsius.
Original Source: ESA News Release
Comets Colliding Inside the Helix Nebula
The latest photograph taken by the Spitzer space telescope shows a bizarre false colour view of the Helix Nebula. Located around 700 light years from Earth, in the constellation of Aquarius, this beautiful nebula used to be a star similar to our own Sun. As it died, it sloughed off its outer layers, creating the view we see today.
It's a beautiful and haunting photograph, but there's some important science in there. The dusty dead star at the heart of the nebula is all that remains, but amazingly, its surrounded by dusty disc of icy material. Where's all this dust coming from? Astronomers think that the death of the star has churned up the region of comets surrounding the star, and we see their collisions.
Enjoy the view while you can. Astronomers think that it'll disappear within 10,000 years or so. The colourful clouds will fade, and all we'll see is tiny White Dwarf ember slowly cooling to the ambient temperature of the Universe. A fate that our Sun will eventually share.
Original Source: Spitzer News Release
Atlantis Prepared for Assembly
The Space Shuttle Atlantis was transported to the Vehicle Assembly Building on Wednesday, beginning the preparations for its assembly. Over the coming days, technicians will attach Atlantis to its external fuel tank, and twin solid rocket boosters.
Following some additional tests, Atlantis will then make the journey to Launch Pad 39-A on February 14. If all goes well, the shuttle will blast off on March 15, 2007 at 6:43am EDT, beginning STS-117's 11-day mission to the International Space Station.
Once in orbit, Atlantis will dock with the station and deliver the S3/S4 integrated truss. The truss includes two additional huge solar panels, which will give the station much more electrical generation capacity. These will be a mirror image to the panels installed in September 2006 by the crew of STS-115.
Original Source: NASA News Release
Imaging Problems for Mars Reconnaissance Orbiter
Although NASA's Mars Reconnaissance Orbiter is about to break the record for science data returned from the Red Planet, it's got a couple of problems that could be getting worse.
In November 2006, spacecraft operators noticed that one of its 14 camera detector pairs has been sending back images with increased noise, such as bad pixels. Unfortunately, this problem has spread, and now 5 other detectors are suffering the same glitch. Although this isn't a big deal on image quality, and the operators have ways of minimizing its impact, they aren't sure if the problem is going to get worse.
The second problem is with the spacecraft's Climate Sounder. This instrument is supposed to map out the planet's temperature, ice clouds and dust distributions on each of 13 orbits it does every day. Unfortunately, the detector started skipping steps in December 2006, so that its field of view has been getting out of position. The errors from the instrument have become more frequent, so it's been taken offline until engineers can figure out a solution.
Original Source: NASA News Release
Distant Quasars Surrounded by Dark matter Halos
Astronomers have taken 4,000 of the brightest quasars and figured out just how much Dark matter surrounds them. As we're starting to learn, wherever there's matter, there's 10x as much dark matter. These quasars back that theory up.
The survey was done using the Sloan Digital Sky Survey (SDSS-II); a detailed data set that will eventually contain more than 25% of the sky. Astronomers are continuously poring through this data, and finding nuggets of information for their theories.
With this latest research, a team of Astronomers led by Yue Shen from Princeton University determined the position of 4,000 bright quasars. Quasars are some of the brightest objects in the Universe, and they're thought to be the radiation emitted by actively feeding supermassive black holes at the hearts of distant galaxies. They're so bright, they can be seen from billions of light-years away, at a time when the universe was only a few billion years old.
Since Dark matter is invisible, how can Astronomers calculate the amount around a quasar? Through gravity. Although Astronomers can't see the dark matter, they can detect its influence on surrounding material, in this case, the quasars.
The researchers developed models of how the quasars should cluster depending on the amount of Dark matter that surrounds them. And this latest survey matched their models. This clustering of Dark matter might have provided the gravity that helped these supermassive black holes acquire their material in the first place, and helped them grow with the Galaxies that surround them.
Original Source: SDSS News Release
Book Review: Many Worlds in One
Does math lead physics or physics lead math? If observing is the source of your information, then physics leads. But, no one's seen the universe age. Yet, as Alex Vilenkin writes in his book Many Worlds in One - The Search for Other Universes, there's lots of both physics and math that tickles our imaginations when we observe the realm in which we live.
As we all know, Earth appears to be a tiny, mot of dust in the grand scheme of the universe. It's much smaller than our solar system, the Milky Way galaxy, and, our local cluster which themselves are small when looking at the broadest extent. Does the universe have a comparative size? This is a consideration that's based on some slick mathematics, together with a liberal dose of the anthropic principle. From these, we see that our universe may have other comparators in addition to its size.
This contemplation of size and composition is the subject that Vilenkin lays out for the reader in his book. With only the briefest of diversions into math, he presents his ideas of our universe's fundamental parameters, its activity, and its residents. Not long ago, much of this subject material would be have been more the subject of science fiction books, if it were considered at all. Now, there's enough evidence to test many considerations.
To provide basis for his own thoughts, Vilenkin brings in first hand discussions with many of today's preeminent physicists. His particular forte is the consideration of the effects of vacuum energy density throughout the life span of our universe. However, he's not ready to commit to any one scheme, as there's not enough evidence nor any means to verify. Thus, he includes ideas from other researchers, even when these are in disagreement with his own. Therefore, the reader will be confident that, even if the arguments are not correct, they are well reasoned.
Given this, the book will most satisfy the reader who enjoys working themselves through reasoning and arguments founded on basic physics. Vilenkin develops many of the arguments, but the reader must be cognizant of electro-magnetism, the four fundamental forces, scalar fields and some recent results from the astronomy community. Without this understanding, the reader may be forced to swim when they don't yet know how to wade in water. And no one gets satisfaction from breathing water. With this, the reader will be in for a well founded dissertation on universes.
This reliance on viewing the issue from physics, though necessary, is a weakness of the book. There is a writing standard for physicists and scientists in general that encourages embellishment. There's other researcher's names, their associated institutes and a quick summary of their work and personal idiosyncrasies. Hence, the reader bounces from alternate universes to wine in France and on to various researchers' homesteads. At times, this is interesting. Often, it distracts. It's as if the writer's decided to combine blackboard presentations with personal anecdotes and few essences of dream visions. This smorgasbord makes for variety, but also a confusing theme in the book
Nonetheless, Vilenkin maintains, throughout his book, a strong association to his subject which is other universes. His book would be excellent for anyone with interest in this subject and willing to invest some time in contemplating some non-traditional concepts. A good grasp of physics helps, but really, who else but physicists and Astronomers are thinking of other universes. This book isn't for those who want spoon feeding or are looking to augment their personal wealth and notoriety. It's for those interested in the immaterial riches of our existence.
The Big Bang introduced our universe. Probability and uncertainty indicate other universes could be popping up every which way. Alex Vilenkin in his book Many Worlds in One - The Search for Other Universes
Many Worlds in One - The Search for Other Universespresents thoughts on what our neighbours may be like. It's worthwhile reading for anyone, particularly before they press the doorbell of our universe's neighbours.
Universe: What's Up this Week: February 12 - February 18, 2007
Monday, February 12 - Celestial scenery alert! As the Moon moves along the ecliptic, it has now neared Jupiter and you'll find the pair less than half a fistwidth apart in the morning skies.
Today is also the anniversary (2001) of NEAR landing on asteroid Eros. The Near Earth asteroid Rendezvous (NEAR) mission was the first to ever orbit an asteroid, successfully sending back thousands of images. Although it was not designed to land on Eros, it survived the low speed impact and continued to send back data. And where is asteroid Eros? You'll find our 11.3 magnitude friend scooting along through Ophiuchus well ahead of the dawn.
Tonight we'll continue onward with our studies of Lepus as we head for two more of the coveted Herschel 400 objects. Our hop starts with beautiful Gamma and NGC 2073.
Located less than a fingerwidth northeast of Gamma (RA 05 45 53.90 Dec -21 59 59.0), NGC 2073 might be magnitude 12.4, but its small size makes it anything but easy. Even if it does have some highly studied molecular cloud structure, be prepared to see nothing but a tiny, egg-shaped contrast change in the elliptical Herschel 241.
Continue northeast a little more than 2 degrees (RA 05 54 52.30 Dec -20 05 03.0) to encounter Herschel 225'NGC 2124. Although it is slightly fainter, we are at least picking up something with more recognizable structure. Oriented north/south, Herschel 225 is an inclined spiral with a bright nucleus. Set in a wonderfully rich star field, it's difficult to spot at first with low power, but its slim structure holds up well to magnification. This one is really a pleasure.
Tuesday, February 13 - If you haven't caught Mercury yet, this evening might be a good opportunity as it reaches its stationary position.
Today is the birthday of J.L.E. Dreyer. Born in 1852, the Danish-Irish Dreyer came to fame as the Astronomer who compiled the New General Catalogue (NGC) published in 1878. Even with a wealth of astronomical catalogs to chose from, the NGC objects and Dreyer's abbreviated list of descriptions still remain the most widely used today.
Tonight let's make Dreyer proud as we finish up our Herschel 400 studies. For binoculars, return again to beautiful star cluster NGC 2017. For Telescopes it's time to head a degree and a half northeast of this anchor for Herschel 267.
At magnitude 13, NGC 2076 is a lot less forgiving of scope size and sky conditions than some galaxies, but if aperture and sky cooperate, you are in for a real treat! Although it is fairly small and somewhat faint, NGC 2076 is an edge-on that will show indications of a dark dustlane across its brighter nucleus, when using aversion. The lane itself has been highly studied for dust extinction and star forming properties and as recently as 2003 a supernova event was reported just south of the nucleus.
Now let's drop south about one degree and pick up Herschel 270!
Far brighter at magnitude 11.9, don't let the ordinary elliptical NGC 2089 fool you. What would appear to be a stellar nucleus is indeed stellar. Studies done by AAVSO have shown that the bright point of light is actually a line of sight star!
Congratulations on your studies and be sure to write down your Herschel 'homework!'
Wednesday, February 14 - Happy Valentine's Day! Today is the birthday of Fritz Zwicky. Born in 1898, Zwicky was the first Astronomer to identify supernovae as a separate class of objects. His insights also proposed the possibility of Neutron stars. Among his many achievements, Zwicky also catalogued Galaxy clusters and designed jet engines.
In mythology, Lepus the Hare is hiding in the grass at Orion's feet. As we have seen, there are many objects of beauty hidden within what seems to be a very ordinary constellation. Before we leave the 'Rabbit' for this year, there is one last object that is worthy of attention. If you look to the feet of Orion and the brightest star of Lepus, you will see that they make a triangle in the sky. Tonight we are headed towards the center of that triangle for a singular object - the Spirograph Nebula.
Shown in all its glory through the eye of the Hubble Telescope, the light you see tonight from the IC 408 planetary nebula left in the year 7 AD. Its central star, much like our own Sol, was in the final stages of its life at that time, and but a few thousand years earlier was a red giant. As it shed its layers off into about a tenth of a light-year of space, only its superheated core remained - its ultraviolet radiation lighting up the expelled gas. Perhaps in several thousand years the nebula will have faded away, and in several billion years more the central star will have become a White Dwarf - a fate that also awaits our own Sun.
At magnitude 11, it is well within reach of a small to mid-size telescope. Like all planetary nebulae, the more magnification - the better the view. The central star is easily seen against a slightly elongated shell and larger Telescopes bring an 'edge' to this nebula that makes it very worthwhile studying. Spend some quality time with this object. With larger scopes, there is no doubt a texture to this planetary that will delight the eye'and touch the heart!
Thursday, February 15 - Born on this day in 1564 was the man who fathered modern astronomy - Galileo Galilei. Two and a half centuries ago, he became first scientist to use a telescope for astronomical observation and his first target was the Moon. Just before dawn this morning you will have the opportunity to observe the waning crescent and the tiny crater named for Galileo. Almost central along the terminator and caught near the edge of Oceanus Procellarum, you will see a small, bright ring. This is Reiner Gamma and you will find Galileo just a short hop to the northwest as a tiny, circular crater. What a shame the cartographers did not pick a more vivid feature to name after the great Galileo! But, look around' Even the skies honor Galileo this morning. Did you spot Mars nearby?
With absence of the Moon in our favor, it's time to learn the constellation of Monoceros as the skies darken and Orion begins to head west. By using the red giant Betelgeuse, diamond-bright Sirius and the beacon of Procyon, we can see these three stars form a triangle in the sky with Sirius pointing towards the south. The 'Unicorn' is not a bright constellation, and most of its stars fall inside this area with its Alpha star almost a handspan south of Procyon.
Using the belt of Orion as a guide, look a handspan east, this is Delta. A fistwidth away to the southeast is Gamma; with Beta about two fingerwidths further along. About a palmwidth southeast of Betelguese is Epsilon. Although this might seem simplistic, knowing these stars will help you find many wonderful objects. Let's start our journey tonight two fingerwidths northwest of Epsilon'
NGC 2186 is a triangular open cluster of stars set in a rich field that can be spotted with binoculars and reveals as many as 30 or more stars to even a small telescope. Not only is this a Herschel 400 object that can be spotted with simple equipment, but a highly studied galactic cluster that contains circumstellar discs!
Friday, February 16 - On this day in 1948, Gerard Kuiper was celebrating his discovery of Miranda - one of Uranus' moons. Just 42 years earlier on this day, both Kopff and Metcalf were also busy - discovering asteroids! Today is the birthday of Francois Arago. Born in 1786, Arago became the pioneer scientist in the wave nature of light. His achievements were many and he is also credited as the inventor of the polarimeter and other optical devices.
Tonight let's celebrate Arago's achievements in polarization as we return again to Epsilon Monocerotis. Our destination is around a fingerwidth east as we seek out another star cluster that has an interesting companion - a nebula!
NGC 2244 is a star cluster embroiled in a reflection nebula spanning 55 light-years and most commonly called 'The Rosette.' Located about 2500 light-years away, the cluster heats the gas within the nebula to nearly 18,000 degrees Fahrenheit, causing it to emit light in a process similar to that of a fluorescent tube. A huge percentage of this light is hydrogen-alpha, which is scattered back from its dusty shell and becomes polarized.
While you won't see any red hues in visible light, a large pair of binoculars from a dark sky site can make out a vague nebulosity associated with this open cluster. Even if you can't, it is still a wonderful cluster of stars crowned by the yellow jewel of 12 Monocerotis. With good seeing, small Telescopes can easily spot the broken, patchy wreath of nebulosity around a well-resolved symmetrical concentration of stars. Larger scopes, and those with filters, will make out separate areas of the nebula which also bear their own distinctive NGC labels. No matter how you view it, the entire region is one of the best for winter skies.
Saturday, February 17 - Tonight is New Moon and perhaps the very best time for us to go hunting some obscure objects that will require the darkest of skies. Once again, we'll use our guidestar Epsilon and tonight we'll be heading about three fingerwidths northeast for a vast complex of nebulae and star clusters.
To the unaided eye, 4th magnitude S Monocerotis is easily visible and to small binoculars so are the beginnings of a rich cluster surrounding it. This is NGC 2264. Larger binoculars and small Telescopes will easily pick out a distinct wedge of stars. This is most commonly known as the 'Christmas Tree Cluster,' its name given by Lowell Observatory Astronomer Carl Lampland. With its peak pointing due south, this triangular group is believed to be around 2600 light-years away and spans about 20 light-years. Look closely at its brightest star - S Monocerotis is not only a variable, but also has an 8th magnitude companion. The group itself is believed to be almost 2 million years old.
The nebulosity is beyond the reach of a small telescope, but the brightest portion illuminated by one of its stars is the home of the Cone Nebula. Larger Telescopes can see a visible V-like thread of nebulosity in this area which completes the outer edge of the dark cone. To the north is a photographic only region known as the Foxfur Nebula, part of a vast complex of nebulae that extends from Gemini to Orion.
Northwest of the complex are several regions of bright nebulae, such as NGC 2247, NGC 2245, IC 446 and IC 2169. Of these regions, the one most suited to the average scope is NGC 2245, which is fairly large, but faint, and accompanies an 11th magnitude star. NGC 2247 is a circular patch of nebulosity around an 8th magnitude star, and it will appear much like a slight fog. IC 446 is indeed a smile to larger aperture, for it will appear much like a small Comet with the nebulosity fanning away to the southwest. IC 2169 is the most difficult of all. Even with a large scope a 'hint' is all!
Enjoy your nebula quest'
Sunday, February 18 - On this day in 1930, a young man named Clyde Tombaugh was very busy checking out some photographic search plates taken with the Lowell Observatory's 13? telescope. His reward? The discovery of Pluto!
This evening let us return to the realm of binoculars and small Telescopes as we head now for Beta Monocerotis and a little more than a fingerwidth north for NGC 2232. This wonderful collection of stars sparkles with chains and various magnitudes - the brightest of which is 5th magnitude 10 Monocerotis. Well resolved with a small telescope, its apparent size of about a full moon-width makes it a true delight and it can even be spotted unaided from a dark sky site. Be sure to note it, because it is on many open cluster study lists.
Now head back to Beta and about the same distance west for Class D cluster NGC 2215. At magnitude 8, it is still within the realm of binoculars, but will look like a small fuzzy patch beyond resolution. Try this one with a telescope! Set in a rich field, the compressed area of near equal magnitude stars isn't the most colorful in the sky, but you can add another to your Herschel hits!
Written by Tammy Plotner.
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