Universe Today

September 5, 2008April 26, 2016 by Ian O'Neill

Goodbye Jules Verne: ATV Undocks From Station

The scene inside ESA mission control as the ATV backs away from the station (ESA)

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Europe’s most advanced robotic spaceship, the Automated Transfer Vehicle (ATV), has effectively ended its 6-month mission to the International Space Station (ISS). It successfully undocked today (Friday) at 21:29 GMT to begin its slow 3 week journey toward the Earth’s atmosphere where it is set for re-entry on September 29th. This was the first ever ATV to be launched and was named after the 19th Century novelist, Jules Verne; another four ATVs are scheduled for construction. Jules Verne’s re-entry is set for night time over an uninhabited region of the Pacific Ocean and NASA will use this opportunity to monitor the fireball so the characteristics of re-entering spacecraft can be studied…

It might seem like a waste – after all, the ATV cost 1.3 billion euros or 1.9 billion dollars to build – but Jules Verne was designed to be a single-use, disposable resupply ship for the space station. However, its duties as a supply ship weren’t restricted to grocery deliveries. After it was launched in March, the ATV underwent a series of tests in space to prepare it for arrival at the station on April 3rd. When attached to the station, the ATV surpassed all expectations and performed many tasks that hadn’t been considered by mission control. Although the ATV provided a valuable re-boost option for the station (four times in total), it also provided the thrust to slow the ISS down to avoid a chunk of satellite debris in August. The ship was also a welcome retreat for the crew of the station, giving them a roomy volume for recreation and cleaning chores. I think Jules Verne will be sorely missed.

So, like the Russian Progress 29 resupply ship that was dropped from the station on Wednesday, Jules Verne was packed up with several tonnes of trash and unwanted equipment from the ISS and jettisoned into space.

The ATV will now use its remaining fuel to park its 13.5 tonne mass in a new orbit for the following three weeks before it is commanded to drop from orbit and begin re-entry. Jules Verne’s fiery suicide will happen at night so scientists can gain an insight into how large objects behave when they burn up in the Earth’s atmosphere. To monitor the event, NASA will deploy two aircraft with radar, UV and other sensors to track the incoming ATV.

“Even though our schedule has been very busy at the ATV Control Centre, I couldn’t have wished for a better mission,” – Herve Come, ESA’s ATV lead mission director.

Sources: ESA, AFP

September 5, 2008December 24, 2015 by Ian O'Neill

Kuiper Belt Object Travelling the Wrong-Way in a One-Way Solar System

Artist impression of two KBOs and Neptune eclipsing the Sun (Mark A. Garlick)

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A strange Kuiper Belt Object (KBO) has been discovered orbiting the Sun in the wrong direction. The object, designated as 2008 KV42 but nicknamed Drac (after Dracula, as vampires are fabled to have the ability to walk on walls), has a highly inclined orbit of 103.5°. Drac is a rarity as very few objects in the Solar System have retrograde orbits; in fact this kind of orbit is usually exclusive to Halley-type comets that have orbits that take them very close to the Sun. Drac on the other hand travels through the Kuiper Belt in a stable orbit at a distance of between 20-70 AU from the Sun. This finding has puzzled astronomers, but Drac may provide clues as to where Halley-type objects originate…

When an object has an inclination of more than 90° from the ecliptic, its direction of motion becomes retrograde when compared with the majority of the Sun’s satellites that share a common, or “prograde” orbital direction. This type of orbit is usually reserved for long-period comets thought to originate from the mysterious Oort Cloud. However, Drac stands out from the crowd as it orbits the Sun from the distance of Uranus to more than twice that of Neptune. Halley-type comets come much closer to the Sun.

Researchers led by Brett Gladman of the University of British Columbia observed the 50 km (30 mile) diameter object in May. Drac (or 2008 KV42) appears to have an extremely stable orbit, and its possibly been that way for hundreds of millions of years. Although Drac orbits through the Kuiper Belt, astronomers do not believe it originates there. “It’s certainly intriguing to ask where it comes from,” says Brian Marsden of the Minor Planet Center in Cambridge, Massachusetts.

Gladman believes the object originated far beyond the Kuiper Belt, possibly from the same volume of space believed to breed Halley-type comets with highly tilted (often retrograde) orbital periods of between 20-200 years. Gladman and his colleagues believe Drac came from a region beyond the Kuiper Belt, but it didn’t come from the Oort Cloud (some 20,000 to 200,000 AU from the Sun). The researchers believe 2008 KV42 was born in a region 2000-5000 AU from the Sun, a theorized volume of the Solar System called the inner Oort Cloud.

It seems likely that Drac was gravitationally disturbed from its home in the inner Oort Cloud by a passing star, or some other disturbance in its local space. It then fell toward the inner Solar System where it found its new home near the Kuiper Belt. Gladman believes that 2008 KV42 may be a “transition object” on its way to becoming a Halley-type comet. However, it will need to be disturbed again before it breaks free of its current stable orbit to fall closer to the Sun.

The British Columbia team have found a collection of 20 KBOs with steeply inclined orbits, but Drac, the vampire of the Solar System, is the only one orbiting in the wrong direction…

Source: New Scientist

September 5, 2008December 24, 2015 by Nancy Atkinson

Black Holes Can Only Get So Big

Ultra-massive black holes, which lurk in the centers of huge galaxy clusters like the one above, seem to have an upper mass limit of 10 billion times that of the Sun. (Credit: NASA)

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Black holes are thought to exist throughout the universe, with the largest and most massive found at the centers of the largest galaxies. These supermassive black holes have been shown to have masses upwards of one billion times that of our own Sun. But an astronomer studying black holes says there’s an upper limit to how big a black hole can get. Priyamvada Natarajan, an associate professor of astronomy and physics at Yale University has shown that even the biggest of these gravitational monsters canâ€™t keep growing forever. Instead, they appear to curb their own growth â€“ once they accumulate about 10 billion times the mass of the Sun.

These ultra-massive black holes, found at the centers of giant elliptical galaxies in huge galaxy clusters, are the biggest in the known universe. Even the large black hole at the center of our own Milky Way galaxy is thousands of times less massive than these behemoths. But these gigantic black holes, which accumulate mass by sucking in matter from neighboring gas, dust and stars, seem unable to grow beyond this limit regardless of where â€“ and when â€“ they appear in the universe. â€œItâ€™s not just happening today,â€ said Natarajan. â€œThey shut off at every epoch in the universe.â€

Natarajan’s study is the first time an upper mass limit has been derived for black holes. Natarajan used existing optical and X-ray data of these ultra-massive black holes to show that, in order for those various observations to be consistent, the black holes must essentially shut off at some point in their evolution.

Artist's conception of a black hole. Credit: U of Tel Aviv

One possible explanation, says Natarajan, is that the black holes eventually reach the point when they radiate so much energy as they consume their surroundings that they end up interfering with the very gas supply that feeds them, which may interrupt nearby star formation. The new findings have implications for the future study of galaxy formation, since many of the largest galaxies in the universe appear to co-evolve along with the black holes at their centers.

â€œEvidence has been mounting for the key role that black holes play in the process of galaxy formation,â€ said Natarajan. â€œBut it now appears that they are likely the prima donnas of this space opera.â€

Source: PhysOrg

September 5, 2008December 24, 2015 by Ian O'Neill

Explore Earth’s Satellites with Google Earth

It's getting crowded out there: active and inactive satellites are tracked (Google/Analytical Graphics)

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OK, I’ve just wasted an hour in simulated space, checking out some of the active and junked satellites orbiting our planet. Google Earth can be an addictive thing at the best of times, but when 13,000 of the satellites in Earth orbit can be viewed by a new plug-in for the program, you may find yourself hooked for longer than usual. The United States Strategic Command keeps very close tabs on what is orbiting our planet and where they are at any given time, and now with the help of Google Earth, you can explore the satellites, plot their orbital trajectories and see just how crowded space can be. Never before have geostationary communication satellites been so interesting!

Just trackin': playing around with the orbital trajectory option (Google/Analytical Graphics)

Tracking space junk is paramount to all our activities in space. Every time we put a “useful” satellite into orbit – to service our communication needs, monitor the weather or spy on other countries – we are amplifying the growing space junk problem surrounding Earth. In February, I wrote a Universe Today article reporting on Google Earth’s ability to plot all known bits of space junk orbiting the Earth. I think it shocked many to see the problem in dazzling 3D. Now a new plug-in has been released detailing the positions of 13,000 alive and dead satellites being tracked by the US military.

At the end of last month, the danger of discarded satellite parts became all too real for the crew of the International Space Station. Nancy wrote about the heroic efforts of the (soon to be dumped) ATV that boosted the station clear of passing debris from a disintegrated Russian satellite. According to officials, the ATV carried out a 5 minute burn, slowing the station and lowering its orbit by 1.5 km (1 mile). The chunk of Russian spy satellite was allowed to pass without incident.

InSat-4, active communications satellites serving India. They're in geosynchronous orbit don't you know? (Google/Analytical Graphics)

Now you can see the space debris being carefully watched by the US and do some satellite tracking yourself. This new Google Earth plug-in (.kmz file for Google Earth) allows you not only to get information on the 13,000 objects tracked by the US Strategic Command, it also lets you plot their orbits. All the way from low Earth to geostationary orbits, you can access information about who launched the satellite, whether it is active or not, its launch date, mass and orbital information (apogee/perigee). By clicking “Display Trajectory in Fixed Frame” in the information panel that appears when you select the satellite, the orbital path is displayed. It is worth noting that this is the orbital trajectory in relation to the Earth’s rotation (or the “fixed frame”), so geostationary satellites will appear to have no orbital motion, as you’d expect.

I spent a long time clicking on the various satellites, constantly surprised by the huge number of inactive satellites there were. I also checked out some information on satellites I’d never heard of (like the active InSat-3A/4B geostationary communication satellites I found oscillating around each other, pictured).

Although it is shocking to see the sheer number of satellites out there (reminding me that Kessler Syndrome could be a very real threat in the future), learning about the stuff orbiting Earth was great fun.

Source: Slashdot

September 5, 2008December 24, 2015 by Nancy Atkinson

New Report: LHC Switch-on Fears Are Completely Unfounded

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We don’t mean to beat a dead horse â€“ both Fraser and Ian have already covered this topic quite thoroughly — but just in case anyone still has any fears about the Large Hadron Collider meaning the end of the world, a new report published today provides the most comprehensive evidence available to confirm that the LHC’s switch-on, due on Wednesday next week, poses no threat to mankind. A copy of the report is available HERE. In a nutshell, it says nature’s own cosmic rays regularly produce more powerful particle collisions than those planned within the LHC, and nothing bad has happened to Earth from those quite natural and frequent events. The LHC will be studying nature’s laws in controlled experiments. So just relax and watch the LHC rap video.

The LHC Safety Assessment Group have reviewed and updated a study first completed in 2003, which dispels fears of universe-gobbling black holes and of other possibly dangerous new forms of matter, and confirms that the switch-on will be completely safe.

The report, ‘Review of the Safety of LHC Collisions’, published in IOP Publishing’s Journal of Physics G: Nuclear and Particle Physics, proves that if particle collisions at the LHC had the power to destroy the Earth, we would never have been given the chance to exist, because regular interactions with more energetic cosmic rays would already have destroyed the Earth or other astronomical bodies.

The Safety Assessment Group compares the rates of cosmic rays that bombard Earth, other planets in our solar system, the Sun and all the other stars in our universe itself to show that hypothetical black holes or strangelets, that have raised fears in some, will in fact pose no threat.

The report also concludes that, since cosmic-ray collisions are more energetic than those in the LHC, but are incapable of producing vacuum bubbles or dangerous magnetic monopoles, we should not fear their creation by the LHC.

LHC collisions will differ from cosmic-ray collisions in that any exotic particles created will have lower velocities, but the Safety Assessment Group shows that even fast-moving black holes produced by cosmic rays would have stopped inside the Earth or other astronomical bodies. Their existence proves that any such black holes could not gobble matter at a risky rate.

As the Safety Assessment Group writes, “Each collision of a pair of protons in the LHC will release an amount of energy comparable to that of two colliding mosquitoes, so any black hole produced would be much smaller than those known to astrophysicists.” They conclude that such microscopic black holes could not grow dangerously.

As for the equally hypothetical strangelets, the review uses recent experimental measurements at the Brookhaven National Laboratory’s Relativistic Heavy-Ion Collider, New York, to prove that they will not be produced during collisions in the LHC.

Source: EurekAlert

September 5, 2008December 24, 2015 by Nancy Atkinson

Sleek, Sexy Spacecraft to Launch Next Week

GOCE: Spacecraft of the future is here! Credit: ESA

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This has to be the sexiest looking spacecraft ever built by humankind. No, it’s not a starship or battle cruiser (although it does look a little like the Eagle spacecraft from the old television show Space: 1999). This sleek, slender, sexy, shiny and sophisticated spacecraft is an Earth-orbiting satellite that will investigate our planet’s gravitational field and map the reference shape of our planet â€“ the geoid – with unprecedented resolution and accuracy. GOCE, or the Gravity field and steady-state Ocean Circulation Explorer is scheduled to launch on Wed. September 10 at 16:21 CEST (14:21 UTC). Why such a sleek design? As GOCE Systems Manager Michael Fehringer says, “Form follows function not only in the world of fashion! To fly low and avoid air drag, the best shape for the satellite to be is long, slender and absolutely symmetrical along the direction of flight.”

ESAâ€™s 1 ton, 5 meter-long spacecraft will be in an extra low orbit (260 km, or 161 miles) and will experience drag from Earth’s upper atmosphere, so smooth and lean helps reduce the friction. Adding to the sleek design is that the solar panels are attached to the long body of the satellite instead of sticking out clumsily and adding to the drag. ESA has a great animation of GOCE in flight. Although the design will help, the spacecraft will need a boost to its orbit occasionally, and has state of the art ion engines.

GOCE will be in a sun-synchronous orbit, meaning it will be almost always be in sunlight, providing a stable thermal environment for the spacecraft.

The instruments are all placed along the axis of the satellite’s body, adding to its sleekness — check out this great animation. GOCE carries a set of six state-of-the-art high-sensitivity accelerometers to measure the components of the gravity field along all three axes. The data collected will provide a high-resolution map of the geoid and of gravitational anomalies. This will greatly improve our knowledge and understanding of the Earthâ€™s internal structure, and will be used as a much-improved reference for ocean and climate studies, including sea-level changes, oceanic circulation and ice caps dynamics survey. Numerous applications are expected in climatology, oceanography and geophysics, as well as for geodetic and positioning activities.

Here’s an interactive feature to take a closer look at the spacecraft.

Oooo. It’s enough to make a girl purr.

Source: ESA
Also, check out Ian’s article on Astroengine

September 5, 2008December 24, 2015 by Tammy Plotner

Weekend SkyWatcher’s Forecast – September 5 – 7, 2008

Greetings, fellow Skywatchers! The weekend has arrived at last and with it… more lunar challenge studies. Are you ready to dance with the pie-eyed piper as we seek out Piccolomini? You’ll find it to the southwest of the shallow ring of Fracastorius on Mare Nectaris’ southern shore. How about seeing double as we take on a few binary stars? It’s time to get out your binoculars and telescopes as we head to the Moon because… Here’s what’s up!

Friday, September 5, 2008 – Tonight let’s discover beauty on our own Moon as we have a look at one of the last lunar challenges of the year which occurs during the first few days of the Moon’s appearance – Piccolomini. You’ll find it to the southwest of the shallow ring of Fracastorius on Mare Nectaris’ southern shore. Piccolomini is a standout lunar feature – mainly because it is a fairly fresh impact crater. Its walls have not yet been destroyed by later impacts, and the interior is nicely terraced. Power up and look carefully at the northern interior wall where a rock slide may have rumbled toward the crater floor. While the floor itself is fairly featureless, the central peak is awesome. Rising a minimum of two kilometers above the floor, it is even higher than the White Mountains in New Hampshire!

When you’ve caught up on your studies, let’s have a look at Beta and Gamma Lyrae, the lower two stars in the “Harp.” Beta is actually a quickly changing variable which drops to less than half the brightness of Gamma in around 12 days. For a few days the pair will seem of almost equal brightness; then you will notice the star closest to Vega begins to fade away. Beta is one of the most unusual spectroscopic stars in the sky, and it is possible that its eclipsing binary companion may be a prototypical “collapsar” (Yep – a black hole!) rather than an actual luminous body.

Now use the telescope for a pair of stars which are very close – Epsilon Lyrae (RA 18 44 20 Dec +39 40 12). Known to most of us as the “Double Double,” look about a fingerwidth northeast of Vega. Even the slightest optical aid will reveal this tiny star as a pair, but the real treat is with a telescope – because each component is a double star! Both sets of stars appear as primarily white, and each pair is very close in magnitude. What is the lowest power that you can use to split them?

Saturday, September 6, 2008 – Today celebrates the founding of the Astronomical and Astrophysical Society of America. Started in 1899, it is now known as the American Astronomical Society. Also on this date, in 2006, the milestone 1500th episode of Jack Horkheimer’s Star Gazer series aired. The long-running short program on public television has led thousands of people, young and old, to “keep on looking up!” For a lifetime of achievement in public outreach, we salute you, Mr. Horkheimer!

Tonight when you have had a look at the Serpentine Ridge, drop south along the terminator and see if you can identify the very old crater Abulfeda, west of Theophilus.

This charming crater was named for Prince Ismail Abu’l Feda, who was a Syrian geographer and astronomer born in the late thirteenth century. Spanning 62 kilometers, its rocky walls show what once was a great depth, but the crater is now filled-in by lava, and drops to a mere 3110 meters below the surface. While it doesn’t appear very large to the telescope, that’s quite big enough to entirely hide Mt. Siple – one of the highest peaks in Antarctica! If conditions are steady, power up and take a look at Albulfeda’s smooth-appearing floor. Can you see many smaller strikes? If the lighting is correct, you might even spot one far younger than the others!

Sunday, September 7 – For binoculars and telescopes, tonight’s Moon will provide a piece of scenic history as we take an in-depth look at crater Albategnius. This huge, hexagonal, mountain-walled plain will appear near the terminator about one-third the way up from the south limb. This 136 kilometer wide crater is approximately 4390 meters deep, and its west wall will cast a black shadow on the dark floor. Albategnius is a very ancient formation, which partially filled with lava at one point in its development. It is home to several wall craters like Klein (which will appear telescopically on its southwest wall). Albategnius holds more than just the distinction of being a prominent crater – it holds a place in history. On May 9, 1962 Louis Smullin and Giorgio Fiocco of the Massachusetts Institute of technology aimed a red laser toward the lunar surface and Albategnius became the first lunar object to be illuminated by a laser and then detected from Earth!

On March 24, 1965 Ranger 9 took this “snapshot” of Albategnius (in the lower right of the lunar image) from an altitude of approximately 2500 kilometers. Companion craters in the image are Ptolemaeus and Alphonsus, which will be revealed for us tomorrow night. Ranger 9 was designed by NASA for one purpose – to achieve a lunar impact trajectory and send back high-resolution photographs and high-quality video images of the lunar surface. It carried no other scientific experiments, and its only destiny was to take pictures right up to the moment of final impact. It is interesting to note that Ranger 9 slammed into Alphonsus approximately 18.5 minutes after the lunar photo was taken. They called that…a “hard landing.”

As the week progresses, watch as the Moon draws closer for a near event with Jupiter by Wednesday. While the pair will still be separated by around two degrees it will still be an awesome sight that doesn’t require a telescope to enjoy!

Wishing you clear skies…

This week’s awesome images are Crater Piccolomini – Credit: Oliver Pettenpaul (LPOD), Beta Lyrae – Credit: Palomar Observatory, courtesy of Caltech, Beta Lyrae – Credit: Palomar Observatory, courtesy of Caltech, Crater Abulfeda – Credit: Wes Higgins, Ranger 9 Image of Lunar Surface and Image of Lunar Surface – Credit: NASA. We thank you!!

September 5, 2008December 24, 2015 by Astronomy Cast

Podcast: Science Fiction at Dragon*Con with Plait and Grazier

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Pamela left Fraser behind (with sorrow) and took on Dragon*Con and the facts (or lack there of) in Science Fiction. Helping her out were special guests Phil Plait and Kevin Grazier.

Click here to download the episode.

Or subscribe to: astronomycast.com/podcast.xml with your podcatching software.

Science Fiction at Dragon*Con with Plait and Grazier show notes.

September 5, 2008December 29, 2015 by Fraser Cain

Carnival of Space #69

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This week, the Carnival of Space is over at Free Space, the blog of Irene Klotz, a correspondent with Discovery News.

Click here to read the Carnival of Space #69

And if you’re interested in looking back, here’s an archive to all the past carnivals of space. If you’ve got a space-related blog, you should really join the carnival. Just email an entry to [email protected], and the next host will link to it. It will help get awareness out there about your writing, help you meet others in the space community – and community is what blogging is all about. And if you really want to help out, let me know if you can be a host, and I’ll schedule you into the calendar.

Finally, if you run a space-related blog, please post a link to the Carnival of Space. Help us get the word out.

September 5, 2008December 24, 2015 by Mark Mortimer

The Quirks and Quarks Guide to Space

The Canadian Broadcasting Corporation provides the eclectic radio show Quirks & Quarks. In it, the hosts serve up hot scientific topics using everyday language so that a general audience can appreciate the significance of recently unravelled marvels. Using the same approach, Jim Lebans presents his book, ‘ The Quirks and Quarks Guide to Space â€“ 42 Questions (and Answers) About Life, the Universe, and Everything‘. And so, with some irreverence and tongue slightly in cheek, Lebans lays in print details of space for the mere mortals amongst us.

For those in the know, 42 is the answer that Douglas Adams provided for the ultimate question. Lebans knowingly uses this to limit his book to 42 chapters. Each chapter has a title in the form of a question such as “How do you loosen the asteroid belt?”. The chapter’s contents then address the question in quite accurate, scientific detail but with great use of analogies and similes. Such as, for star formation, he states that “Iron is to stars what kryptonite is to Superman and what garlic is to vampires. It can stop them dead and ultimately destroy them”. Or, “Going to the black hole in the centre of the galaxy will be like visiting New York after a lifetime in Wyoming”. Now these may sound facetious but they’re necessary and successful in meeting Lebans’ apparent objective of getting hard science into the average person’s mind. And, the use of a chapter per question keeps things simple and easily re-locatable.

So where’s the value you ask? This book is for those who have next to no scientific training but have an interest. School teachers can use the chapters to build their comprehension before teaching their class. Non-scientists can find out the value and urgency of space exploration (e.g. Chapter 23 â€“ How long until we have to leave the Earth?). And, those people without a glint of technical comprehension but a slimmer of interest would be learning about space and smiling at the same time. What more would you want?

So before you think that science has left the ground without you onboard, check out Jim Lebans’ book, ‘ The Quirks and Quarks Guide to Space â€“ 42 Questions (and Answers) About Life, the Universe, and Everything‘. You’ll be learning and chuckling at the same time.