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Powerful Solar Winds Colliding Head On.
Off to one corner of NGC 346, a star cluster in the Small Magellanic Cloud, there's an amazing collision between two stars. Well, not the stars themselves, but the powerful winds they're ejecting.
The two stars are collectively known as HD 5980. They're a binary system of stars separated by only 90 million kilometres; this is roughly half the distance from the Earth to the Sun. One star has 50 times the mass of the Sun, while the other weighs in at 30 times the mass of the Sun. And both are radiating more than a million times the energy of the Sun. It's good to know they're a whole Galaxy away from us.
And both stars are producing terrifyingly strong solar winds, each dumping the mass of the Earth into space every month, and then accelerating this mass away with the pressure from all the photons they're emitting. Since the stars are so close to each other, their solar winds interact. And where those solar winds collide' look out.
New images from ESA's XMM-Newton Observatory measured the X-ray output from this collision zone, and found that the energy from only X-rays is 10 times the amount of energy output by our own Sun. By studying the interaction between the winds, Astronomers will be able to calculate how they change over time.
Original Source: ESA News Release
Satellites Reveal Subglacial Streams in Antarctica
Although it looks ancient and unchanging, the ice sheet in Antarctica is a surprisingly active place. Deep beneath the sheet's surface, there are waterways, channels and pipes that connect various subglacial 'lakes'. These channels can cause these lakes to drain away into the ocean, or transfer water from one to the other.
Now data gathered by NASA satellites shows these fast-moving ice streams in action. The satellites - Terra, Aqua and ICESat - are able to measure changes in ice elevation as small as 1 metre (3 feet). As a subglacial lake drains, the elevation of ice above it falls accordingly.
These subglacial rivers seem to play an important role in the movement, growth and decay of the ice sheets above them. They could contribute a surprisingly large amount of the fresh water dumped into the nearby coastal oceans.
Original Source: NASA News Release
New Crater Discovered on Titan
NASA's Cassini spacecraft captured this image of a semi-circular feature on Saturn's Moon Titan. Planetary geologists think that it might be a relatively recent impact crater on Titan. This would be surprising, since all the data gathered on Titan shows that its surface is relatively young, constantly weathered and resurfaced by weather conditions - only three impact craters have been found on Titan so far.
The image was captured with Cassini's radar mapper during its January 13, 2007 flyby of Titan. The crater is about 180 km (110 miles) wide, and the bright material around the dark centre is the ejecta blanket hurled out during the impact. The inner crater is dark; for radar images, that means it's a smooth surface, possibly from deposits covering the inside of the crater.
Original Source: NASA/JPL/SSI News Release
Martian Explorers Should Be Looking for Fossils
Instead of just looking for current life on Mars, Arizona State University professor Jack Farmer thinks that future missions should also be looking for ancient fossils on the Red Planet. In fact, he thinks they might be easier to find.
Jack Farmer, a professor of geological sciences, presented his work at the annual meeting of the American Association for the Advancement of Science in San Francisco. Instead of performing exobiology - where rovers look for current life - he thinks exopaleontology will be easier.
The problem with looking for life right now is that it requires liquid water. And finding liquid water on the surface of Mars is going to be very tough. If it's there at all, liquid water is going to be underground or under thick sheets of ice. But fossilized bacteria might just be sitting right there on the surface of Mars, waiting for a rover to scoop it up and analyze it.
Instead of looking for liquid water, you just need to find a location where water once existed for some period of time. For example, where the Mars Exploration Rovers, Spirit and Opportunity, are currently roaming. In order to see fossilized bacteria, the rovers would need to be equipped with extremely sensitive microscopes and organic Chemistry laboratories to analyze promising rocks.
It won't be easy, but it's probably easier than getting to liquid water.
Original Source: ASU News Release
NASA's THEMIS Mission Blasts Off
NASA's THEMIS mission was blasted into space on Saturday, February 17 atop a Delta II rocket. THEMIS stands for time History of Events and Macroscale Interactions during Substorms, and it's comprised of 5 separate spacecraft.
Each of the 128-kg (282-pound) spacecraft is equipped with identical instrumentation. They will fly in different positions between the Earth and the Sun to help measure the interaction between the solar wind and the Earth's magnetosphere. Some of the energy created by this interaction causes magnetic field lines to stretch and snap like rubber bands. We see the snaps as beautiful auroral displays.
The spacecraft are currently making their way to their final science orbits, which they should reach in mid-September.
Original Source: NASA News Release
Lasers Could Deflect Future asteroids From Impacting Earth
The Earth has been bombarded by asteroids in the past, and it's going to happen again in the future. It's not a question of 'if', it's a question of 'when'. Keenly aware of the problem, scientists are working on strategies that could prevent an asteroid with Earth in its cross hairs from impacting us.
One interesting technique is being worked on at the University of Alabama in Huntsville. The strategy would involved placing a laser system into space, or at a future Moon base. When a potential Earth-crossing asteroid is discovered, the laser would target it and fire for a long period of time. A small amount of material would be knocked off the surface of the asteroid, which would deflect its orbit slightly. Over a long period of time, the asteroid course correction would add up, turning a direct hit into a near miss.
A laser system like this is a long way off, but a system could be developed sooner that could focus on asteroids and help measure their properties and precisely track their orbits, helping remove some of the uncertainty.
Original Source: UAH News Release
Exoplanet is Hot and Dry
Astronomers working with the Spitzer space telescope announced a tremendous new advance today, when they used the great observatory to successfully analyze the atmosphere of two distant planets. This is an enormously important discovery, and we'll deal with the implications of this in a second.
First, though, let's talk about what they turned up.
The planets are known as HD 209458b and HD 189733b. These are your typical hot Jupiters, orbiting their parent stars at extremely close distances. Astronomers originally estimated that these planets should have large quantities of water in their atmospheres. Surprisingly, though, the Spitzer data showed that they're drier and cloudier than expected. The discoverers think the water is there, it's just hidden beneath the clouds. It's also possible that the planets have large quantities of silicate dust, which obscures the view to water.
Now, let's talk about the impact of this. Think for a second. Astronomers have used a space telescope to study the atmosphere of a planet orbiting another star. Obviously, a hot jupiter, with temperatures in the thousands of degrees isn't a good place to look for life. But think of it as a dress rehearsal; an opportunity to fine tune techniques and instruments.
This technique will come in handy in the coming years when more powerful Telescopes are launched, capable of finding rocky planets orbiting other stars. Once one of those Telescopes turns up large quantities of oxygen in the atmosphere of another star, you've got a good candidate for life. I can hardly wait.
Original Source: Spitzer News Release
NASA's Next Probe Should Visit Europa
Arizona State University professor Ronald Greeley thinks that NASA's next flagship mission to the outer planets should be sent to Europa, to help determine if the Jovian Moon is a good place to search for life. Greeley presented his rationale at the annual meeting of the American Association for the Advancement of Science in San Francisco.
According to Greeley, Europa has all the basic ingredients for life: a source of energy, organic chemistry, and hopefully' liquid water. When NASA's Galileo spacecraft visited Europa, it discovered that the moon's surface seems to be covered in a thick layer of ice. scientists were intrigued at the possibility that under all that ice there's an ocean of liquid water. And where there's water, there could be life.
As Europa orbits Jupiter, it experiences tides. An ocean underneath the ice will rise and fall each day, and a spacecraft in orbit equipped with a high-precision altimeter should be able to measure these tides. If it's ice all the way down, the ice should only flex a little bit, but if the ice shell is thin, the ice could rise and fall more than 40 metres (130 feet) each day.
A new mission to Europa should be able to give scientists an answer, and help them determine if the ice shell is thin enough to allow a probe to drill through the ice and search for life in the ocean.
Original Source: ASU News Release
Rosetta Approaches its Mars Flyby
If you're waiting for the Rosetta mission to really pay off, you're going to need a lot of patience. The ESA spacecraft isn't due to meet up with its target, Comet 67P Churyumov Gerasimenko, until 2014. But there's a little science coming on February 25th, when the spacecraft swings by Mars.
Rosetta will make its closest approach to the Red planet at 0153 GMT, February 25th, passing only 250 km above the surface. The primary objective of this flyby is to give the spacecraft a speed boost, using Mars' gravity to increase its velocity. Rosetta already made a flyby past Earth in 2005, and will perform another in November 2009.
As part of its Martian flyby, Rosetta will be operating all of its instruments for two days before and after the closest encounter. It'll be gathering data about the surface of Mars, the atmosphere and its interaction with the solar wind and take photos of its two satellites, Phobos and Deimos.
Original Source: PPARC News Release
New Survey of the Gamma Ray Skies
ESA's Integral spacecraft has released a new survey of the sky, seen in gamma rays - the most energetic radiation we know of. This latest survey brings the total sky coverage to 70%.
Integral has been producing this survey for 3 years now. During its first year, the spacecraft focused mainly on objects near the centre of the Milky Way, and turned up about 120 source. Now into its third year, the spacecraft has uncovered a total of 421 gamma ray sources.
Each of these sources are probably exotic binary objects, like black holes Neutron stars, or actively feeding supermassive black holes. But about a quarter of these sources are totally unexplained. Astronomers have a few theories, like they're star systems shrouded in dust, or a rare class of objects called cataclysmic variable stars.
Original Source: ESA News Release
Book Reviews: Mars a Technical Tale / Reference Guide to the ISS
Apogee Books have cornered themselves a great niche in publishing books related to space. Their offerings span from the most recent to some dated but vintage fare. Yet all of them seem to add another little sparkle to the crown of our Outer space ventures. The following is a review of two of their recent publications.
A recently published though dated book is 'Project Mars - A Technical Tale' by Wernher von Braun. It was written in 1949. However, this is the first time it's been published. Given the author and the time of writing, this book should have some fascinating contents, and it delivers. It exemplifies the management strengths of von Braun. It showcases his expectations of interplanetary flight as well as Mars environs. Recall that humans had yet to fly in space or send anything into orbit when this was written. And lastly, it presents some social and philosophical issues about exploration and meeting life on other planets. All these have relevance to today's space undertakings and thus the book provides a chance to see where we've progressed and where we're standing still.
The book's tale is of a future unified humanity on Earth sending a return mission to Mars. The premise is simple, as are the the characters and plot. Though billed as science fiction, this really is a thinly veiled technical overview of how to travel to Mars. This is not surprising, as a voyage there was always von Braun's goal. Therefore, the people are mere backdrops, as the precedence is the technology marvel of a human spacecraft fleet that assembles, travels to Mars, meets a few locals and heads home again. Ideas get developed, technology advanced and everyone's content. This, coupled with an appendix full of equations and formulae, clearly show that von Braun's book came from a technophile.
If the reader is willing to forgo strong plots and vibrant characters, there's lots of interest in this technical tale. Anyone interested in today's efforts to travel to Mars would gain much from reading this. There might be some chuckles about details, given what 50 years have taught us. But, there's also reference to many unanswered common issues, such as why undertake this expedition. Those interested in the sociological aspects of space flight or accepting no space flight would also be intrigued with von Braun's views. At the least, it should be a mainstay in the libraries at the Mars analogue stations.
Even in 1949, there were some intoxicating ideas about Mars. Wernher von Braun's book 'Project Mars - A Technical Tale' built on many of the perceptions of space travel of his time and showed that people could successfully travel vast distances in space. The capability remains, and as shown in the book, we just need the will.
At the other end of Apogee's space faring timeline is today's major accomplishment. Here, Apogee publishes NASA's 'Reference Guide to the International Space Station'. This is an original NASA publication, NASA SP-2006-557, which Apogee is reformatting to bring to a wider audience. This book, edited by Gary Kitmacher, compiles a wonderful collage of humanity's furthest space outpost.
This book is effectively a pictorial guide of the modules that are making up and will make up the space station. Nearly all pictures are from the U.S or other national space agencies. Many are of the space station in orbit, while a sprinkling are of modules that are awaiting their turn to join this research station. Filling out the assembly are computer graphics and artists' impressions of the space station of the future, as modules combine to complete the finishing touches.
So what does this book satisfy aside from being a glossy promotion of our future home in the sky? It's greatest strength is to give to the reader a visual appreciation of the appearance of the station and its components. Break outs of systems and their emplacement on an outline of the station's cross section shows the reader some of the lower level elements. For example, there's the Human Research Facility, the Minus Eighty-Degree Laboratory Freezer and the Atmosphere Grab Sample Container. It's an excellent high-level guide of the station's technical aspect and would probably have warmed Wernher von Braun's heart.
With all the pictures and few words, this book is well suited for those unfamiliar and curious. The pictures emphasize the reality of the endeavor. The breadth and detail emphasize the complexity. And though there's solid indication of the benefits of international partners, there's also hints of the challenges of collaboration, given the number of nodes and the segregation of modules. Nevertheless, both learners and teachers would benefit greatly from having this reference guide to show that humanity can and has taken a step to being a space faring species.
Humanity can come together and continue building on our advances. In the book, the 'Reference Guide to the International Space Station' edited by Gary Kitmacher, there's clear evidence that multi-national collaborations are possible and fruitful. The reader can see that our technological capabilities can turn dreams into reality.
Universe: What's Up this Week: February 19 - February 25, 2007
Monday, February 19 - Today is the birthday of Nicolas Copernicus. Born in 1473, he was the creator of the modern solar system model which illustrated the retrograde motion of the outer planets. Considering this was well over 530 years ago, and in a rather 'unenlightened' time, his revolutionary thinking about what we now consider natural is astounding.
While we still have dark skies on our side, let's head for a handful of difficult nebulae in a region just west of Gamma Monocerotis.
For binoculars, check out the region around Gamma, it is rich in stars and very colorful! You are looking at the very outer edge of the Orion spiral arm of our galaxy. For small scopes, have a look at Gamma itself - it's a triple system that we'll be back to study. For larger scopes? It's Herschel hunting time'
NGC 2183 and NGC 2185 will be the first you encounter as you move west of Gamma. Although they are faint, just remember they are nothing more than a cloud of dust illuminated by faint stars on the edge of the galactic realm. The stars that formed inside provided the light source for these wispy objects and at their edges lies intergalactic space.
To the southwest is the weaker NGC 2182, which will appear as nothing more than a faint star with an even fainter Halo about it, with NGC 2170 more strongly represented in an otherwise difficult field. While the views of these objects might seem vaguely disappointing, you must remember that not everything is as bright and colorful as seen in a photograph. Just knowing that you are looking at the collapse of a giant molecular cloud that's 2400 light-years away is pretty impressive!
Tuesday, February 20 - Today in 1962, John Glenn became the first American to orbit the Earth three times while aboard Friendship 7.
Today in history also celebrates the Mir space station launch in 1986. Mir (Russian for 'peace') was home to both cosmonauts and astronauts as it housed 28 long duration crews during its 15 years of service. To date it is one of the longest running space stations and a triumph for mankind. Spaseba!
Tonight the slender first crescent of the Moon makes its presence known on the western horizon. Before it sets, take a moment to look at it with binoculars. The beginnings of Mare Crisium will show to the northeast quadrant, but look just a bit further south for the dark, irregular blotch of Mare Undarum - the Sea of Waves. On its southern edge, and to lunar east, look for the small Mare Smythii - the 'Sea of Sir William Henry Smyth.' Further south of this pair and at the northern edge of Fecunditatis is Mare Spumans - the 'Foaming Sea.' All three of these are elevated lakes of aluminous basalt belonging to the Crisium basin.
For telescope users, wait until the Moon has set and return to Beta Monocerotis and head about a fingerwidth northeast for an open cluster challenge - NGC 2250. This vague collection of stars presents itself to the average telescope as about 10 or so members that form no real asterism and makes one wonder if it is indeed a cluster. So odd is this one, that a lot of star charts don't even list it!
Wednesday, February 21 - Tonight the Moon begins its westward journey after sunset in a position much easier to observe. The lunar feature we are looking for is at the north-northeast of the lunar limb and its view is often dependent on libration. What are we seeking? 'The Sea of Alexander von Humboldt''
Mare Humboldtianum is seen in this picture as fully revealed, yet sometimes it can be hidden from view because it is an extreme feature. Spanning 273 kilometers, the basin in which it is contained extends for an additional 600 kilometers and continues around to the far side of the Moon. The mountain ranges which accompany this basin can sometimes be glimpsed under perfect lighting conditions, but ordinarily are just seen as a lighter area. The mare was formed by lava flow into the impact basin, yet more recent strikes have scarred Humboldtianum. Look for a splash of ejecta from crater Hayn further north, and the huge, 200 kilometer strike of crater Bel'kovich on Humboldtianum's northeast shore.
When the Moon begins to wester, let's head for Beta Monocerotis and hop about 3 fingerwidths east for an 8.9 magnitude open cluster that can be spotted with binoculars and is well resolved with a small telescope - NGC 2302. This very young stellar cluster resides at the outer edge of the Orion spiral arm. While binoculars will see a handful of stars in a small V-shaped pattern, telescope users should be able to resolve 40 or so fainter members.
Thursday, February 22 - Today in 1966, Soviet space mission Kosmos 110 was launched. Its crew was canine, Veterok (Little Wind) Ugolyok (Little Piece of Coal); both history making dogs. The flight lasted 22 days and held the record for living creatures in orbit until 1974 - when Skylab 2 carried its three-man crew for 28 days.
With tonight's Moon in a much higher position to observe, let's begin with an investigation of Mare Fecunditatis - the Sea of Fertility.
Stretching 1463 kilometers in diameter, the combined area of this mare is equal in size to the Great Sandy Desert in Australia - and almost as vacant in interior features. It is home to glasses, pyroxenes, feldspars, oxides, olivines, troilite and metals in its lunar soil, which is called regolith. Studies show the basaltic flow inside of the Fecunditatis basin perhaps occurred all at once, making its chemical composition different from other maria. The lower titanium content means it is between 3.1 and 3.6 billion years old!
The western edge of Fecunditatis is home to features we share terrestrially - grabens. These down-dropped areas of landscape between parallel fault lines occur where the crust is stretched to the breaking point. On Earth, these happen along tectonic plates, but on the Moon they are found around basins. The forces created by lava flow increase the weight inside the basin, causing a tension along the border which eventually fault and cause these areas. Look closely along the western shore of Fecunditatis where you will see many such features.
(1) Taruntius, (2) Secchi, (3) Messier and Messier A, (4) Lubbock, (5) Guttenberg, (6) Montes Pyrenees, (7) Goclenius, (8) Magelhaens, (9) Columbo, (10) Webb, (11) Langrenus, (12) Lohse, (13) Lame, (14) Vendelinus, (15) the Luna 16 landing site
Friday, February 23 - In 1987, Ian Shelton made an astonishing visual discovery - SN 1987a. This was the brightest supernova in 383 years.
Since the stars of our study constellation of Monoceros are quite dim when the Moon begins to interfere, why not spend a few days really taking a look at the Moon's surface and familiarizing yourself with its many features? Tonight would be a great time for us to explore 'The Sea of Nectar.'
At around 1000 meters deep, Mare Nectaris covers an area of the Moon equal to that of the Great Sandhills in Saskatchewan, Canada. Like all maria, it is part of a gigantic basin that is filled with lava, and evidence of grabens exists along its western basin edge. While Nectaris' basaltic flows appear darker than those in most maria, it is one of the older formations on the Moon and as the terminator progress, you'll be able to see where ejecta belonging to Tycho crosses its surface.
For now? Let's have a closer look at the mare itself and its surrounding craters' Enjoy these many features which are also lunar challenges - and we'll be back to study each later in the year!
(1) Isidorus, (2) Madler, (3) Theophilus, (4) Cyrillus, (5) Catharina, (6) Dorsum Beaumont, (7) Beaumont, (8) Fracastorius, (9) Rupes Altai, (10) Piccolomini, (11) Rosse, (12) Santbech, (13) Pyrenees Mountains, (14) Guttenberg, (15) Capella
Saturday, February 24 - Tonight let your imagination sweep you away as we go mountain climbing - on the Moon! Tonight all of Mare Serenitatis will be revealed and along its northwestern shore lie some of the most beautiful mountain ranges you'll ever view - The Caucasus to the north and the Apennines to the south.
Like it's earthly counterpart, the Caucasus Mountain range stretches almost 550 kilometers and some of its peaks reach upwards to 6 kilometers - a summit as high as Mount Elbrus!
Slightly smaller than its terrestrial namesake, the lunar Apennine mountain range extends some 600 kilometers with peaks rising as high as 5 kilometers. Be sure to look for Mons Hadley, one of the tallest peaks that you will see at the northern end of this chain. It rises above the surface to a height of 4.6 kilometers, making that single mountain about the size of asteroid Toutatis.
Today in 1968, during a radar search survey, the first pulsar was discovered by Jocelyn Bell. The co-directors of the project, Antony Hewish and Martin Ryle, matched these observations to a model of a rotating Neutron star, winning them the 1974 physics Nobel Prize and proving a theory of J. Robert Oppenheimer from 30 years earlier.
Would you like to get a look at a region of the sky that contains a pulsar? Then wait until the Moon has well westered and look for guidestar Alpha Monocerotis to the south and bright Procyon to its north. By using the distance between these two stars as the base of an imaginary triangle, you'll find pulsar PSR 0820+02 at the apex of your triangle pointed east. In the picture below, I wonder which 'star' it is?
Sunday, February 25 - Tonight your lunar assignments are relatively easy. We will begin by identifying 'The Sea of Vapors.'
Look for Mare Vaporum on the southwest shore of Mare Serenitatis. Formed from newer lava flow inside an old crater, this lunar sea is edged to its north by the mighty Apennine Mountains. On its northeastern edge, look for the now washed-out Haemus Mountains. Can you see where lava flow has reached them? This lava has come from different time periods and the slightly different colorations are easy to spot even with binoculars.
Further south and edged by the terminator is Sinus Medii - 'The Bay in the Middle.' With an area about the size of both Massachusetts and Connecticut, this lunar feature is the mid-point of the visible lunar surface. In 1930, experiments were underway to test this region for surface temperature - a project begun by Lord Rosse in 1868. Surprisingly enough, results of the two studies were very close, and during full daylight temperatures in Sinus Medii can reach the boiling point as evidenced by Surveyors 4 and 6 - which landed near its center.
Now take a hop north of Mare Vaporum for a look at 'The Rotten Swamp' - Palus Putredinus. More pleasingly known as the 'Marsh of Decay,' this nearly level surface of lava flow is also home to a mission - the hard-landing of Lunik 2. On September 13, 1959 Astronomers in Europe reported seeing the black dot of the crashing probe. The event lasted for nearly 300 seconds and spread over an area of 40 kilometers
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