New theoretical models now confirm that it could be forged in the merger events of two neutron stars. Image: Natural gold nuggets from California and Australia; Natural History Museum, London
[/caption]Here on Earth the practice of alchemy once had its era – trying to turn lead into gold. However, somewhere out there in the universal scheme of things, that process is a reality and not a myth. Instead of a scientist desperately looking for a sublime formula, it just might happen when neutron stars merge in a violent collision.
We’re all aware of the nuclear fusion manner in which elements are created from stars. Hydrogen is burned into helium, and so up the line until it reaches iron. It’s just the way stellar physics work and we accept it. To date, science has theorized that heavier elements were the creation of supernovae events, but new studies done by scientists of the Max Planck Institute for Astrophysics (MPA) and affiliated to the Excellence Cluster Universe and of the Free University of Brussels (ULB) indicate they may be able to form during encounters with ejected matter from neutron stars.
”The source of about half of the heaviest elements in the Universe has been a mystery for a long time,“ says Hans-Thomas Janka, senior scientist at the Max Planck Institute for Astrophysics (MPA) and within the Excellence Cluster Universe. ”The most popular idea has been, and may still be, that they originate from supernova explosions that end the lives of massive stars. But newer models do not support this idea.“
Although it might take millions of years for such a tryst to take place, it’s not impossible for two neutron stars in a binary system to eventually meet. Scientists at the MPA and the ULB have now simulated all stages of the processes through computer modeling and taken note at the formation of chemical elements which are the offspring.
”In just a few split seconds after the merger of the two neutron stars, tidal and pressure forces eject extremely hot matter equivalent to several Jupiter masses,“ explains Andreas Bauswein, who carried out the simulations at the MPA. Once this so-called plasma has cooled to less than 10 billion degrees, a multitude of nuclear reactions take place, including radioactive decays, and enable the production of heavy elements. ”The heavy elements are `recycled’ several times in various reaction chains involving the fission of super-heavy nuclei, which makes the final abundance distribution become largely insensitive to the initial conditions provided by the merger model,“ adds Stephane Goriely, ULB researcher and nuclear astrophysics expert of the team.
Their findings agree well with observations of abundance distributions in both the Solar System and old stars. When compared with possible neutron star collisions occurring in the Milky Way, the conclusions are the same – this speculation could very well be the explanation for the distribution of heavier elements. The team plans on continuing their studies while on the look out “for detecting the transient celestial sources that should be associated with the ejection of radioactive matter in neutron star mergers.” Like a supernova event, the heat from the radioactive decay will shine like… well…
Gold in the dark.
Original Story Source: Max Planck Institut News. For Further Reading: R-process nucleosynthesis in dynamically ejected matter of neutron star mergers.
Three people enjoy the summer sky over the Delaware river, NJ, USA in August 2006. Image Credit: Wikimedia
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It’s a great time to be an amateur astronomer! Nowadays, “backyard” astronomers armed with affordable CCD imagers, high-quality tracking mounts, inexpensive PC’s and the internet at their fingertips are making real contributions to Astronomy science.
How are people in their backyards contributing to real science these days?
Consider that in 1991, the Hubble Space Telescope launched with a main camera of less than 1 megapixel. (HST’s array was 800×800 pixels – just over half a megapixel). Currently, “off-the-shelf” imaging equipment available for a few hundred dollars or less easily provides 1 megapixel or more. Even with a “modest” investment, amateurs can easily reach the ten megapixel mark. Basically, the more pixels you have in your imaging array, the better resolution your image will have and the more detail you’ll capture (sky conditions notwithstanding).
With access to fairly high resolution cameras and equipment, many amateurs have taken breathtaking images of the night sky. Using similar equipment other hobbyists have imaged comets, supernovae, and sunspots. With easy access to super-precise tracking mounts and high-quality optics, it’s no wonder that amateur astronomers are making greater contributions to science these days.
One spectacular example of amateur discoveries was covered by Universe Todayearlier this year. Kathryn Aurora Gray, a ten year old girl from Canada, discovered a supernova with the assistance of her father and another amateur astronomer, David Lane. The discovery of Supernova 2010lt (located in galaxy UGC 3378 in the constellation of Camelopardalis) was Kathryn’s first, her father’s seventh and Lane’s fourth supernova discovery. You can read the announcement regarding Ms. Gray’s discovery courtesy of The Royal Astronomical Society of Canada at: http://www.rasc.ca/artman/uploads/sn2010lt-pressrelease.pdf
Often times when a supernova is detected, scientists must act quickly to gather data before the supernova fades. In the image below, look for the blinking “dot. The image is a before and after image of the area surrounding Supernova 2010lt.
A before and after animation of Supernova 2010lt. Credit: Dave Lane
Before Kathyrn Gray, astronomer David Levy made headlines with his discovery of comet Shoemaker-Levy 9. In 1994, comet Shoemaker-Levy 9 broke apart and collided with Jupiter’s atmosphere. Levy has gone on to discover over twenty comets and dozens of asteroids. Levy has also published several books and regularly contributes articles to various astronomy publications. If you’d like to learn more about David Levy, check out his internet radio show at http://www.letstalkstars.com/, or visit his site at http://www.jarnac.org/
Hubble image of comet P/Shoemaker-Levy 9, taken on May 17, 1994. Image Credit: H.A. Weaver, T. E. Smith (Space Telescope Science Institute), and NASAThe International Space Station and Space Shuttle Atlantis transiting the sun. Image Credit: Thierry Legault
Rounding out news-worthy astronomers, astrophotographer Thierry Legault has produced many breathtaking images that have been featured here on Universe Today on numerous occasions. Over the past year, Thierry has taken many incredible photos of the International Space Station and numerous images of the last few shuttle flights. Thierry’s astrophotography isn’t limited to just the sun, or objects orbiting Earth. You can read more about the objects Thierry captures images of at: http://www.astrophoto.fr/ You can also read more about Thierry and the equipment he uses at: http://legault.perso.sfr.fr/info.html
Performing science as an amateur isn’t limited to those with telescopes. There are many other research projects that ask for public assistance. Consider the Planet Hunters site at: http://www.planethunters.org/. What Planet Hunters aims to achieve is a more “hands-on” approach to interpreting the light curves from the publicly available data from the Kepler planet finding mission. Planet Hunters is part of the Zooniverse, which is a collection of citizen science projects. You can learn more about the complete collection of Zooniverse projects at: http://www.zooniverse.org
Another citizen science effort recently announced is the Pro-Am White Dwarf Monitoring (PAWM) project. Led by Bruce Gary, the goal of the project is to explore the possibility of using amateur and professional observers to estimate the percentage of white dwarfs exhibiting transits by Earth-size planets in the habitable zone. The results from such a survey are thought to be useful in planning a comprehensive professional search for white dwarf transits. You can read more about the PAWM project at: http://www.brucegary.net/WDE/
Transit simulation. Image Credit: Manuel Mendez/PAWM
One very long standing citizen project is the American Association of Variable Star Observers (AAVSO). Founded in 1911, the AAVSO coordinates, evaluates, compiles, processes, publishes, and disseminates variable star observations to the astronomical community throughout the world. Currently celebrating their 100th year, the AAVSO not only provides raw data, but also publishes The Journal of the AAVSO, a peer-reviewed collection of scientific papers focused on variable stars. In addition to data and peer reviewed journals, the AAVSO is active in education and outreach, with many programs, including their mentor program designed to assist with disseminating information to educators and the public.
If you’d like to learn more about the AAVSO, including membership information, visit their site at: http://www.aavso.org/
For over a decade, space enthusiasts across the internet have been taking part in SETI@Home. The official description of SETI@home is “a scientific experiment that uses Internet-connected computers in the Search for Extraterrestrial Intelligence (SETI)”. By downloading special client software from the SETI@Home website at http://setiathome.berkeley.edu/, volunteers from around the world can help analyze radio signals and assist with SETI’s efforts to find “candidate” radio signals. You can learn more about SETI@Home by visiting http://setiathome.berkeley.edu/sah_about.php
The projects and efforts featured above are just a small sample of the many projects that non-scientists can participate in. There are many other projects involving radio astronomy, galaxy classification, exoplanets, and even projects involving our own solar system. Volunteers of all ages and educational backgrounds can easily find a project to help support.
Ray Sanders is a Sci-Fi geek, astronomer and space/science blogger. Visit his website Dear Astronomer and follow on Twitter (@DearAstronomer) or Google+ for more space musings.
It’s back by popular demand! Here’s a new Where In The Universe Challenge. Name where in the Universe this image was taken depicts and give yourself extra points if you can name the telescope or spacecraft responsible for the image. Post your guesses in the comments section, and check back on later at this same post to find the answer. To make this challenge fun for everyone, please don’t include links or extensive explanations with your answer. Good luck!
UPDATE: The answer has now been posted below.
This is a Chandra image of four bright, variable X-ray sources that were discovered within 3 light years of Sagittarius A* (Sgr A*). The variability suggests these are X-ray binary systems where a black hole or neutron star is pulling matter from a nearby companion star. Such a high concentration of X-ray binaries in this region is strong circumstantial evidence that a dense swarm of 10,000 or more stellar-mass black holes and neutron stars has formed around Sgr A*.
The "invisible" world Kepler-19c, seen in the foreground of this artist's conception, was discovered solely through its gravitational influence on the companion world Kepler-19b - the dot crossing the star's face. Kepler-19b is slightly more than twice the diameter of Earth, and is probably a "mini-Neptune." Nothing is known about Kepler-19c, other than that it exists. Credit: David A. Aguilar (CfA)
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There’s a planet out there playing a game of ‘doorbell ditch’ with astronomers. Scientists can’t see this distant world, but they know it’s there because its gravity is having a noticeable effect on the orbit of a neighboring planet.
“It’s like having someone play a prank on you by ringing your doorbell and running away,” said astronomer Sarah Ballard of the Harvard-Smithsonian Center for Astrophysics (CfA), lead author on a new paper published in the The Astrophysical Journal. “This invisible planet makes itself known by its influence on the planet we can see.”
The planetary system of the visible and stealthy planets was discovered by the Kepler spacecraft, and the two worlds orbit a Sun-like star named Kepler-19. The system is located 650 light-years from Earth in the constellation Lyra. The 12th-magnitude star is well placed for viewing by backyard telescopes on September evenings in the northern hemisphere.
Launched in 2009, NASA’s Kepler spacecraft hunts for extra-solar planets around stars other than our Sun by watching for planets orbiting in front of their stars. These “transiting” planets block some of the starlight, and that’s how astronomers “see” that a planet is there.
However, the planet and star must line up exactly for us to see a transit.
That was the case for the first planet, Kepler-19b. It transits its star every 9 days and 7 hours, at a distance of 8.4 million miles from the star, where it is heated to a temperature of about 900 degrees Fahrenheit. The great thing about transits is that astronomers can deduce the planet’s physical size: the greater the dip in light, the larger the planet relative to its star. Kepler-19b has a diameter of 18,000 miles, making it slightly more than twice the size of Earth. It may resemble a “mini-Neptune,” however its mass and composition remain unknown.
If Kepler-19b were alone, each transit would follow the next like clockwork. Instead, the transits come up to five minutes early or five minutes late. Such transit timing variations show that another world’s gravity is pulling on Kepler-19b, alternately speeding it up or slowing it down.
If this sounds somewhat familiar, the planet Neptune in our own solar system was discovered similarly. Astronomers tracking Uranus noticed that its orbit didn’t match predictions. They realized that a more distant planet might be nudging or pulling on Uranus and calculated the expected location of the unseen world. Telescopes soon observed Neptune near its predicted position.
But this is the first time this method has been used to find a previously unknown planet in another solar system. Astronomers say no other current technique we have could have found the unseen companion.
“This method holds great promise for finding planets that can’t be found otherwise,” stated Harvard astronomer and co-author David Charbonneau.
So far, astronomers don’t know anything about the invisible world Kepler-19c, other than that it exists. It weighs too little to gravitationally tug the star enough for them to measure its mass. And Kepler hasn’t detected it transiting the star, suggesting that its orbit is tilted relative to Kepler-19b.
“Kepler-19c has multiple personalities consistent with our data. For instance, it could be a rocky planet on a circular 5-day orbit, or a gas-giant planet on an oblong 100-day orbit,” said co-author Daniel Fabrycky of the University of California, Santa Cruz (UCSC).
The Kepler spacecraft will continue to monitor Kepler-19 throughout its mission. Those additional data will help nail down the orbit of Kepler-19c. Future ground-based instruments like HARPS-North will attempt to measure the mass of Kepler-19c. Only then will we have a clue to the nature of this invisible world.
I’ve got a poster that says, “All I Needed to Know About Life, I Learned from Star Trek.” Why? Because it’s true. We all know we need to seek out new life and new civilizations, and to always keep your phaser on stun. Oh, and always follow the Prime Directive, too.
It was 45 years ago today that the first Star Trek original series show premiered on television. To celebrate, I’m NOT wearing a red shirt, and I’ll share videos of the intro from the original series, above, and below, a blooper reel from the 1960’s. It’s sure to make any Trekkie smile. Continue reading “45 Years Ago Today, Star Trek Beamed Into Our Lives”
GRAIL and its Delta 2 rocket on the launchpad. Credit: Alan Walters (awaltersphoto.com) for Universe Today.
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High upper level winds put a damper on hopes for launching the GRAIL mission on its first attempts on Thursday, September 8. While the weather looked perfect on the ground at Kennedy Space Center, weather balloons showed high winds in the region of the atmosphere where the Delta 2 launcher would normally experience the most turbulence.
NASA will try again on Friday, September 9 with two one-second launch windows available at 8:33 and 9:12 EDT (12:33 or 13:12 UT). There were two one-second launch windows for Thursday, and both were “red” because of the winds aloft.
The dynamic duo twin-spacecraft Gravity Recovery and Interior Laboratory (GRAIL) mission is designed to map the Moon’s gravity with extreme precision.
This picture shows the illuminated man-made border between India and Pakistan,the line snaking through the landscape, as seen from the International Space Station on August 21, 2011. Of the hundreds of clusters lights, the largest are the capital cities of Islamabad, Pakistan, and New Delhi, India. Credit: NASA/Ron Garan
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There is an oft-repeated and perhaps beautiful saying that you can’t see political borders from space. Well, it turns out that saying isn’t true; not anymore. ISS astronaut Ron Garan took this image recently which clearly shows the border between India and Pakistan. Since 2003, India has illuminated the border with Pakistan by floodlights in attempt to prevent ammunition trafficking and the infiltration of terrorists.
“Since the beginning of human spaceflight fifty years ago, astronauts have reflected on how peaceful, beautiful, and fragile the Earth looks from space,” Garan wrote on his Fragile Oasis blog. “These reflections are not clichés that astronauts say because it feels good. It is truly moving to look at the Earth from space.”
But seeing this clearly visible political border was sobering for Garan and his crewmates.
“Realizing what this picture depicted had a big impact on me,” he said. “When viewed from space, Earth almost always looks beautiful and peaceful. However, this picture is an example of man-made changes to the landscape in response to a threat, clearly visible from space. This was a big surprise to me.”
Garan added, however, that the point here is not that we can look down at the Earth and see a man-made border between India and Pakistan. “The point is that we can look down at that same area and feel empathy for the struggles that all people face,” he said. “We can look down and realize that we are all riding through the Universe together on this spaceship we call Earth, that we are all interconnected, that we are all in this together, that we are all family.”
Garan said he believes our world is a place where possibilities are limited only by our imagination and our will to act. “It is within our power to eliminate the suffering and poverty that exist on our planet,” he said.
If it turns out that astronauts do have to leave the International Space Station unmanned, at least Dextre, the Canadian Space Agency’s robotic handyman, will be there to take care of things until humans return. Above is a sped-up video showing the work done recently by Dextre, replacing a faulty circuit-breaker box outside the station. Curiously, the robot did most of this work while the astronauts inside were sleeping. Imagine, dozing peacefully inside your sleep station and hearing a knocking sound outside the module…. Continue reading “Robot Works on Repairs While ISS Astronauts Sleep”
Schematic view of Cluster C3 and C1 satellite trajectories Copyright: ESA
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Every now and again, a sudden pulse of energy in Earth’s magnetosphere just cuts loose. As a result, we have a bright polar auroral display. While we’re beginning to understand more about magnetism and the Sun/Earth connection, there’s still a few rogues left in the gallery. Just what is a geomagnetic substorm and what does it do?
Although we’ve known about them for years, the exact process behind a geomagnetic substorm has been a mystery… one that’s being solved with data from missions like ESA’s Cluster spacecraft. Earth is continually being bathed in incoming sheets of electrons and protons – the product of an active Sun. These highly energized particles are simply a part of solar winds flowing from coronal holes and even powerful blasts from events like coronal mass ejections. For the most part, we’re shielded by the magnetosphere – but sometimes a wee bit escapes and collects in the magnetotail – stored like a battery charge. At a point, it’s released… and when it does, it re-arranges our magnetic field lines. The energy then conducts itself along these lines like a filament in a light bulb. When the watts hit the fan? Wow… We have polar aurora!
It’s not a new concept, but there’s never been a clear understanding of where these geomagnetic storms originate. Do they come from a sudden disruption of electric current about 64 000 km from the planet? Or are the created by a process called magnetic reconnection which occurs much further down the magnetotail, at a distance of around 125 000 – 200 000 km? If you remember our recent study of Alfven waves, then you know current consensus points towards the reconnection theory. But there’s only one problem. Alfven waves are slow movers, traveling at a reconnection speed of about 250 seconds. What we’re seeing is an event that occurs about 60 seconds after reconnection… and the birth of a new movement. The kinetic Alfven wave (KAW).
“We ran a very simple system, and simulated how the reconnection event released energy in the plasma sheet of charged particles,” said Shay. “We were looking for a faster mechanism for propagating the signal from the explosion than the Alfven waves that were already widely recognized.”
Unlike its predecessor which motivates both ions and electrons, the KAW only excites the electron, moving them through the plasma at twice the speed. Through simulations, it’s been proved the kinetic Alfven wave could be spawned by reconnection, move away from the explosion and activate aurora. The data was returned by the Fluxgate Magnetometer (FGM) and the Electric Fields and Waves (EFW) instrument and found by Jonathan Eastwood, a Research Fellow at The Blackett Laboratory, Imperial College London.
“I found 18 events which occurred at the time the four spacecraft were flying through the tail region,” said Dr. Eastwood. “The fast signal predicted by Michael Shay showed up in the Cluster data, supporting the theory that kinetic Alfven waves generated by reconnection were rapidly energizing the auroras.”
“It’s rather like what happens in a thunderstorm,” he added. “The fast-moving lightning flash arrives first, followed some time later by the slower sound waves of the thunderclap.”
Delta II Heavy rocket will blast GRAIL missions to the moon from Launch Pad 17B. Delta II rocket and twin GRAIL satellites are enclosed inside the Mobile Service Tower at Cape Canaveral Air Force Station. Credit: Ken Kremer
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Another American rocket Era is about to end. The venerable Delta II rocket, steeped in history, will fly what is almost certainly its final mission from Cape Canaveral. And it will do so quite fittingly by blasting twin satellites to the moon for NASA on a unique path for a truly challenging mission to do “extraordinary science”.
On Sept. 8, the most powerful version of the Delta II, dubbed the Delta II Heavy, is slated to launch NASA’s duo of GRAIL lunar mappers on an unprecedented science mission to unlock the mysteries of the moons deep interior. There are two instantaneous launch windows at 8:37:06 a.m. and 9:16:12 a.m. EDT lasting one second each.
“GRAIL simply put, is a journey to the center of the moon,” said Ed Weiler, NASA Associate Administrator of the Science Mission Directorate in Washington,DC at a pre-launch briefing for reporters on Sept. 6.
“It will probe the interior of the moon and map its gravity field by 100 to 1000 times better than ever before. We will learn more about the interior of the moon with GRAIL than all previous lunar missions combined.”
View of Delta II rocket looking out to Atlantic Ocean from upper level of Launch Complex 17. ULA and GRAIL logos painted on side of 8 ft diameter Delta rocket. Credit: Ken Kremer
GRAIL will depart Earth from Space Launch Complex 17B (SLC-17B) at Cape Canaveral Air Force Station, Florida, which is also the last scheduled use of Pad 17B.
GRAIL logo painted on the side of Delta II Rocket 1st Stage. Photo taken from inside upper level of launch gantry. GRAIL stands for Gravity Recovery and Interior Laboratory. Credit: Ken Kremer
“Trying to understand how the moon formed, and how it evolved over its history, is one of the things we’re trying to address with the GRAIL mission,” says Maria Zuber, principal investigator for GRAIL from the Massachusetts Institute of Technology. “But also, (we’re) trying to understand how the moon is an example of how terrestrial planets in general have formed.”
“GRAIL is a mission that will study the inside of the moon from crust to core,” Zuber says.
Delta II Heavy rocket is augmented by 9 wider diameter solid rocket motors providing more thrust. Credit: Ken Kremer
So far there have been 355 launches of the Delta II family, according to NASA’s Delta II Launch Manager Tim Dunn. The Delta II is built by United Launch Alliance.
“GRAIL is the last contracted Delta II mission to be launched from Complex 17. And it will be the 356th overall Delta to be launched. Complex 17 at the Cape has a proud heritage of hosting 258 of those 355 total Delta launches to date.
Hypergolic propellants have been loaded onto the 2nd stage after assessing all the preparations for the rocket, spacecraft, the range and facilities required for launch.
“The Launch Readiness Review was successfully completed and we can proceed with the countdown,” said Dunn.
The Delta II Heavy is augmented with nine larger diameter ATK solid rocket motors.
The Mobile Service Tower will be rolled back from the Delta II rocket tonight, starting at about 10:30 p.m. EDT depending on the weather.
The weather forecast for launch remains very iffy at a 60% percent chance of “NO GO” according to NASA and Air Force officials.
A launch decision will be made tomorrow morning Sept. 8 right after the weather briefing but before fueling begins at 6:30 a.m.
The weather forecast for rollback of the Mobile Service Tower tonight remains generally favorable. There is a 40% chance of a weather issue at 10:30 p.m. which drops to 30% after midnight. Tower rollback can be pushed back about 2 hours without impacting the countdown, says NASA.
Weather remains at 60% NO GO in case of a 24 hour delay but improves over the weekend. The team has about 42 days time in the launch window.
After entering lunar orbit, the two GRAIL spacecraft will fly in a tandem formation just 55 kilometers above the lunar surface with an average separation of 200 km during the three month science phase.
Stay tuned to Universe Today for updates overnight leading to liftoff at 8:37 a.m.
See my photo album from a recent tour of Launch Complex 17 and the Mobile Service Tower
GRAIL Flying in Formation. Using a precision formation-flying technique, the twin GRAIL spacecraft will map the moon's gravity field. The mission also will answer longstanding questions about Earth's moon, including the size of a possible inner core, and it should provide scientists with a better understanding of how Earth and other rocky planets in the solar system formed. GRAIL is a part of NASA's Discovery Program.
