Tammy was a professional astronomy author, President Emeritus of Warren Rupp Observatory and retired Astronomical League Executive Secretary. She’s received a vast number of astronomy achievement and observing awards, including the Great Lakes Astronomy Achievement Award, RG Wright Service Award and the first woman astronomer to achieve Comet Hunter's Gold Status.
(Tammy passed away in early 2015... she will be missed)
Vital clues about the devastating ends to the lives of massive stars can be found by studying the aftermath of their explosions. In its more than twelve years of science operations, NASA's Chandra X-ray Observatory has studied many of these supernova remnants sprinkled across the Galaxy. Credit: X-ray: NASA/CXC/SAO/I.Lovchinsky et al, IR: NASA/JPL-Caltech
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Located some 14,700 light years from the Earth toward the center of our galaxy, a newly photographed supernova remnant cataloged as G350.1+0.3 is making astronomers scratch their heads. The star which created this unusual visage is suspected to have blown its top some 600 to 1,200 years ago. Although it would have been as bright as the event which created the “Crab”, chances are no one saw it due to the massive amounts of gas and dust at the Milky Way’s heart. Now NASA’s Chandra X-ray Observatory and the ESA’s XMM-Newton telescope has drawn back the curtain and we’re able to marvel at what happens when a supernova imparts a powerful X-ray “kick” to a neutron star!
Credit: X-ray: NASA/CXC/SAO/I.Lovchinsky et al, IR: NASA/JPL-CaltechPhotographic proof from Chandra and XMM-Newton are full of clues which give rise to the possibility that a compact object located in the influence of G350.1+0.3 may be the core region of a shattered star. Since it is off-centered from the X-ray emissions, it must have received a powerful blast of energy during the supernova event and has been moving along at a speed of 3 million miles per hour ever since. This information agrees with an “exceptionally high speed derived for the neutron star in Puppis A and provides new evidence that extremely powerful ‘kicks’ can be imparted to neutron stars from supernova explosions.”
As you look at the photo, you’ll notice one thing in particular… the irregular shape. The Chandra data in this image appears as gold while the infrared data from NASA’s Spitzer Space Telescope is colored light blue. According to the research team, this unusual configuration may have been caused by the stellar debris field imparting itself into the surrounding cold molecular gas.
These results appeared in the April 10, 2011 issue of The Astrophysical Journal. The scientists on this paper were Igor Lovchinsky and Patrick Slane (Harvard-Smithsonian Center for Astrophysics), Bryan Gaensler (University of Sydney, Australia), Jack Hughes (Rutgers University), Stephen Ng (McGill University), Jasmina Lazendic (Monash University Clayton, Australia), Joseph Gelfand (New York University, Abu Dhabi), and Crystal Brogan (National Radio Astronomy Observatory).
Russia to Start Own Search for Extrasolar Planets - Photo: Paul A. Kempton
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Located just south of Saint Petersburg on Pulkovo Heights, one of the greatest Russian Observatories of all times – the Pulkovo Observatory – is about to embark on a very noble study. According to the head of the Institute for Space Research, Lev Zelyony, the Soviet telescopes are about to turn their eyes towards deep skies in search of extrasolar planets. “Scientists from the Pulkovo Observatory are planning to use ground-based instruments to study the transit of planets around their parent stars,” Zelyony said at a roundtable meeting at RIA Novosti headquarters in Moscow.
The observatory was absolutely state-of-the-art when it opened for business in 1839 and employed Wilhelm von Struve as its director. It houses some of the largest refractor telescopes in the world, including a 38-cm (15 in.) aperture refractor and a 30-inch (76 cm) refractor – both built by Alvan Clarke and Sons. Fifty years later, they added an astrophysical laboratory, a mechanical workshop and installed one of Europe’s largest lensed telescope, a 76-cm refractor (30 inch). Later additions to the observatory included a Littrow spectrograph and horizontal solar telescope and the facility blossomed into a world leader in stellar spectroscopy, cataloging and more. Modern improvements include astrograph equipment, an interferometer, radio telescope and even an additional 65-cm (26-inch) refractor. The Pulkovo Observatory is up to the task.
Pulkovo Observatory 2004 - Credit: Vladimir Ivanov
The hunt for exoplanets is one of the most popular aspects of modern astronomy and one of the fastest growing fields. In less than 25 years, 755 and an ever-increasing number of planets have been cataloged… and the research just doesn’t end. The United States Kepler Mission and French CoRoT space telescope have had their share of fun, but using a ground-based telescope could also be a viable source of planet detection, Zelyony said. He also cited the example of the Hungarian Automated Telescope Network (HATNet) which so far has discovered 29 exoplanets. By using the transit detection method, the Russian astronomers are eager to begin observations where a small change in magnitude could mean a big change in the way their telescopes perceive the stars.
“It is an interesting research, which should be pursued,” Zelyony said. “It will also help us look at our Solar System from a different perspective.”
Gifford Miller collects vegetation samples on Baffin Island. (Photo courtesy University of Colorado Boulder.)
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In a study led by the University of Colorado Boulder with co-authors at the National Center for Atmospheric Research (NCAR) and other organizations, researchers may have possibly found evidence the “Little Ice Age” may have had ties to an unusual era of volcanic activity… one that lasted for about 50 years. In just five decades, four massive tropical volcanic eruptions managed to take Earth’s entire environment and put it on ice. Somewhere near the years between 1275 and 1300 A.D., these eruptions caused some very cool summer weather in the northern hemisphere which triggered an expansion of sea ice that – in turn – weakened Atlantic currents. However, it didn’t weaken the already cool climate. It strengthened it.
The international study was done in layers – like a good cake – but instead of sweet frosting, it was a composite look at dead vegetation, ice and sediment core data. By engaging highly detailed computer climate modeling, scientists are now able to have a strong theory of what triggered the Little Ice Age.. a theory which begins with decreased summer solar radiation and progresses through erupting volcanoes. Here planet-wide cooling could have been started by sulfates and other aerosols being ejected into our atmosphere and reflecting sunlight back into space. Simulations have shown it could have even been a combination of both scenarios.
“This is the first time anyone has clearly identified the specific onset of the cold times marking the start of the Little Ice Age,” says lead author Gifford Miller of the University of Colorado Boulder. “We also have provided an understandable climate feedback system that explains how this cold period could be sustained for a long period of time. If the climate system is hit again and again by cold conditions over a relatively short period—in this case, from volcanic eruptions—there appears to be a cumulative cooling effect.”
“Our simulations showed that the volcanic eruptions may have had a profound cooling effect,” says NCAR scientist Bette Otto-Bliesner, a co-author of the study. “The eruptions could have triggered a chain reaction, affecting sea ice and ocean currents in a way that lowered temperatures for centuries.” The team’s research papers will be published this week in Geophysical Research Letters. Members of the group include co-authors from the University of Iceland, the University of California Irvine, and the University of Edinburgh in Scotland. The study was funded in part by the National Science Foundation, NCAR’s sponsor, and the Icelandic Science Foundation.
“Scientific estimates regarding the onset of the Little Ice Age range from the 13th century to the 16th century, but there is little consensus,” Miller says. It’s fairly clear these lower temperatures had an impact on more southerly regions such as South American and China, but the effect was far more clear in areas such as northern Europe. Glacial movement eradicated populated regions and historical images show people ice skating in places known to be too warm for such solid freezing activities before the Little Ice Age.
“The dominant way scientists have defined the Little Ice Age is by the expansion of big valley glaciers in the Alps and in Norway,” says Miller, a fellow at CU’s Institute of Arctic and Alpine Research. “But the time in which European glaciers advanced far enough to demolish villages would have been long after the onset of the cold period.”
By employing the technique of radiocarbon dating, approximately 150 plant specimens, complete with roots, were gathered from the receding edges of ice caps located on Baffin Island in the Canadian Artic. In these samples they found evidence of a “kill date” which ranged between 1275 and 1300 A.D. This information led the team to surmise the plants were quickly frozen and then just as quickly encased in solid ice. A second documented kill date occurred about 1450 A.D. showing another major event. To further flesh out their findings, the research team took sediment sample cores from a glacial lake which is linked to the mile-high Langikull ice cap. These important samples from Iceland can be reliably dated back as far as 1,000 years and the results showed a sudden increase in ice during the late 13th century and again in the 15th. Thanks to these techniques which rely on the presence tephra deposits, we know these climate cooling events occurred as a result of volcanic eruptions.
“That showed us the signal we got from Baffin Island was not just a local signal, it was a North Atlantic signal,” Miller says. “This gave us a great deal more confidence that there was a major perturbation to the Northern Hemisphere climate near the end of the 13th century.”
What brought the team to their final conclusions? Through the use of the Community Climate System Model developed by scientists at NCAR and the Department of Energy with colleagues at other organizations, they were able to simulate the impact of volcanic cooling on the extent and mass of Artic sea ice. The model painted a portrait of what could have occurred from about 1150 to 1700 A.D. and showed that some large scale eruptions could have impacted the northern hemisphere if they happened within a close time frame. In this scenario, the long term cooling effect could have expanded the Artic Sea ice to the point where it eventually met – and melted – in the North Atlantic. During the modeling, the solar radiation was set at a constant to show ” the Little Ice Age likely would have occurred without decreased summer solar radiation at the time.” concluded Miller.
During the initial stage of sunspot emergence and cooling, the formation of H2 may trigger a temporary "runaway" magnetic field intensification. The magnetic field prevents the flow of energy from inside the sun to the outside, and the sunspot cools as the energy shines into space. They form hydrogen molecules that take half the volume of the atoms, thus dropping pressure and concentrating the magnetic field, and so on. (adapted from Jaeggli, 2011; sunspot image by F. Woeger et al
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Although well over 40 years old, the Dunn Solar Telescope at Sunspot, New Mexico isn’t going to be looking at an early retirement. On the contrary, it has been outfitted with the new Facility Infrared Spectropolarimeter (FIRS) and is already making news on its solar findings. FIRS provides simultaneous spectral coverage at visible and infrared wavelengths through the use of a unique dual-armed spectrograph. By utilizing adaptive optics to overcome atmospheric “seeing” conditions, the team took on seven active regions on the Sun – one in 2001 and six during December 2010 to December 2011 – as Sunspot Cycle 23 faded away. The full sunspot sample has 56 observations of 23 different active regions… and showed that hydrogen might act as a type of energy dissipation device which helps the Sun get a magnetic grip on its spots.
“We think that molecular hydrogen plays an important role in the formation and evolution of sunspots,” said Dr. Sarah Jaeggli, a recent University of Hawaii at Manoa graduate whose doctoral research formed a key element of the new findings. She conducted the research with Drs. Haosheng Lin, also from the University of Hawaii at Manoa, and Han Uitenbroek of the National Solar Observatory in Sunspot, NM. Jaeggli now is a postdoctoral researcher in the solar group at Montana State University. Their work is published in the February 1, 2012, issue of The Astrophysical Journal.
You don’t have to be a solar physicist to know about the Sun’s 11 year cycle, or to understand how sunspots are cooler areas of intense magnetism. Believe it or not, even the professionals aren’t quite sure of how all the mechanisms work… especially those which cause sunspot forming areas that retard normal convective motions. Of the things we’ve learned, the spot’s inner temperature has a correlation with its magnetic field strength – with a sharp rise as the temperature cools. “This result is puzzling,” Jaeggli and her colleagues wrote. It implies some undiscovered mechanism inside the spot.
NOAA 11131 sunspot region (Dec. 6, 2010) was the most intense spot measured in this study, but far from the largest the Sun can produce. The two bottom images show the strength of the magnetic field (C) and the contrast between the interior of the spot and the surrounding photosphere (D). The first graph (A) shows how OH starts to appear in the penumbra and continues to rise as the magnetic field strength rises. Because OH forms at a lower temperature than H2, its presence implies the quantity of hydrogen molecules that could be present (B). (adapted from Jaeggli et al, 2012)
One theory is that hydrogen atoms combining into hydrogen molecules may be responsible. As for our Sun, the majority of hydrogen is ionized atoms because the average surface temperature is assessed at 5780K (9944 deg. F). However, since Sol is considered a “cool star”, researchers have found indications of heavy-element molecules in the solar spectrum – including surprising water vapor. These type of findings might prove the umbral regions could allow hydrogen molecules to combine in the surface layers – a prediction of 5% made by the late Professor Per E. Maltby and colleagues at the University of Oslo. This type of shift could cause drastic dynamic changes where gas pressure is concerned.
“The formation of a large fraction of molecules may have important effects on the thermodynamic properties of the solar atmosphere and the physics of sunspots,” Jaeggli wrote.
With direct measurements being beyond our current capabilities, the team then measured a proxy – the hydroxyl radical made of one atom each of hydrogen and oxygen (OH). According to the National Solar Observatory, “OH dissociates (breaks into atoms) at a slightly lower temperature than H2, meaning H2 can also form in regions where OH is present. By coincidence, one of its infrared spectral lines is 1565.2nm, almost the same as the 1565nm line of iron, used for measuring magnetism in a spot and one of the lines FIRS is designed to observe.”
Spectral lines are the unique "fingerprints in light" that all atoms and molecules produce. In the presence of a magnetic field in a hot gas, some lines split, betraying the presence and strength of the magnetic fields. Each line corresponds to electrons giving up energy in discrete amounts, or quanta, as light. Imposing a magnetic field on the atom makes the electrons produce multiple lines instead of one. The spread of these lines is a direct measure of the strength of the magnetic field, and is greater in the red and in the infrared spectrum. This image depicts sunspot spectra taken by FIRS with lines centered at 630.2nm (left) and 1564.8nm (right). Note the broadened area in the color ellipses, indicating line splitting inside a spot, and how the broadening is greater at the longer wavelength. Contrast is adjusted to enhance visibility in the inset boxes.
By combining both old and new data, the team measured magnetic fields across sunspots, and the OH intensity inside spots, judging the H2 concentrations. “We found evidence that significant quantities of hydrogen molecules form in sunspots that are able to maintain magnetic fields stronger than 2,500 Gauss,” Jaeggli commented. She also said its presence leads to a temporary “runaway” intensification of the magnetic field.
As for the anatomy of a sunspot, magnetic flux boils up from the Sun’s interior and slows surface convection – which in turns stops cooler gas which has radiated its heat into space. From there, molecular hydrogen is created, reducing the volume. Because it is more transparent than its atomic counterpart, its energy is also radiated into space allowing the gas to cool even more. At this point the hot gas primed by the flux compresses the cooler region and intensifies the magnetic field. “Eventually it levels out, partly from energy radiating in from the surrounding gas. Otherwise, the spot would grow without bounds. As the magnetic field weakens, the H2 and OH molecules heat up and dissociate back to atoms, compressing the remaining cool regions and keeping the spot from collapsing.”
For now, the team admits that additional computer modeling is required to validate their observations and that most of the active regions so far have been mild ones. They’re hoping that Sunspot Cycle 24 will give them more fuel to be “cool”…
Artist concept of the twin Radiation Belt Storm Probes spacecraft, scheduled for launch in August 2012. Credit: NASA
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During the 1950s and just before the great “Space Race” began, scientists like Kristian Birkeland, Carl Stormer, and Nicholas Christofilos had been paying close attention to a theory – one that involved trapped, charged particles in a ring around the Earth. This plasma donut held in place by our planet’s magnetic field was later confirmed by the first three Explorer missions under the direction of Dr. James Van Allen. Fueled by perhaps solar winds, or cosmic rays, the knowledge of their existence was the stuff of nightmares for an uniformed public. While the “radiation” can affect objects passing through it, it doesn’t reach Earth, and this realization quickly caused fears to die. However, there are still many unanswered questions about the Van Allen Radiation Belts that mystify modern science.
Over the years we’ve learned these radiation zones are comprised of electrons and energetically charged particles. We’ve documented the fact they can both shrink and swell according to the amount of solar energy they receive, but what researchers haven’t been able to pinpoint is exactly what causes these responses. Particles come and particles go – but there isn’t a solid answer without evidence. A pertinent question has been to determine if particles escape into interplanetary space when the belts shrink – or do they fall to Earth? Up until now, it’s been an enigma, but a new study employing several spacecraft at the same time has been to trace the particles and follow the trail up.
“For a long time, it was thought particles would precipitate downward out of the belts,” says Drew Turner, a scientist at the University of California, Los Angeles, and first author on a paper on these results appearing online in Nature Physics on January 29, 2012. “But more recently, researchers theorized that maybe particles could sweep outward. Our results for this event are clear: we saw no increase in downward precipitation.”
From October to December 2003, the radiation belts swelled and shrank in response to geomagnetic storms as particles entered and escaped the belts. Credit: NASA/Goddard Scientific Visualization Studio
This isn’t just a simple answer to simple question, though. Understanding the movement of the particles can play a critical role in protecting our satellite systems as they pass through the Van Allen Belts – and its far reaching radiation extensions. As we know, the Sun produces copious amounts of charged particles in the stellar winds and – at times – can blast in our direction during coronal mass ejections (CMEs) or shock fronts caused by fast solar winds overtaking slower winds called co-rotating interaction regions -CIRs). When directed our way, they disrupt Earth’s magnetosphere in an event known as a geomagnetic storm. During a “storm” the radiation belt particles have been known to decrease and empty the belt within hours… a depletion which can last for days. While this is documented, we simply don’t know the cause, much less what causes the particles to leave!
In order to get a firmer grip on what’s happening requires multiple spacecraft measuring the changes at multiple points at the same time. This allows scientists to determine if an action that happens in one place affects another elsewhere. While we look forward to the Radiation Belt Storm Probes (RBSP) mission results, it isn’t scheduled to launch until August 2012. In the interim, researchers have combined data from two widely separated spacecraft to get an early determination of what happens during a loss event.
“We are entering an era where multi-spacecraft are key,” says Vassilis Angelopoulos, a space scientist at UCLA, and the principal investigator for THEMIS and a coauthor on the paper. “Being able to unite a fleet of available resources into one study is becoming more of a necessity to turn a corner in our understanding of Earth’s environment.”
So where did this early support information come from? Fortunately the team was able to observe a small geomagnetic storm which occurred on January 6, 2011. By engaging the the three NASA THEMIS (Time History of Events and Macroscale Interactions during Substorms) spacecraft, two GOES (Geostationary Operational Environment Satellite), operated by the National Oceanic and Atmospheric Administration (NOAA), and six POES (Polar Operational Environmental Satellite), run jointly by NOAA, and the European Organization for the Exploitation of Meteorological Satellites (EUMETSAT) spacecraft, they were able to catch electrons moving close to the speed of light as they dropped out of the belt for over six hours. Orbiting Earth’s equatorial zones, the THEMIS and GOES spacecraft are just part of the team. The POES spacecraft passes through the radiation belts several times a day as it cruises at a lower altitude and near the poles. By combining data, the scientists were able to take several observational vantage points and proved – without a doubt – that the particles left the belt by way of space and did not return to Earth.
“This was a very simple storm,” says Turner. “It’s not an extreme case, so we think it’s probably pretty typical of what happens in general and ongoing results from concurrent statistical studies support this.”
During this time, the spacecraft also observed a low-density area of the Van Allen belts which appeared along the periphery and traveled inward. This appeared to be an indication the particles were outward bound. If this was a normal occurrence, it stands to reason that a type of “wave” must assist the motion, allowing the particles to reach the outer escape boundary. Discovering just what exactly triggers this escape mechanism will be one of the jobs for RBSP, says David Sibeck at NASA’s Goddard Space Flight Center in Greenbelt, Md., who is NASA’s mission scientist for RBSP and project scientist for THEMIS.
“This kind of research is a key to understanding, and eventually predicting, hazardous events in the Earth’s radiation belts,” says Sibeck. “It’s a great comprehensive example of what we can expect to see throughout the forthcoming RBSP mission.”
Clouds play a vital role in Earth's energy balance, cooling or warming Earth's surface depending on their type. This painting, "Cumulus Congestus," by JPL's Graeme Stephens, principal investigator of NASA's CloudSat mission, depicts cumulus clouds, which transport energy away from Earth's surface. Image credit: Graeme Stephens
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Like many of us, Earth works on a budget – an energy budget. However, this energy isn’t the type that powers our automobiles or electric lights. It’s the energy that empowers our living planet. When it comes to input and output, the Earth is a huge throughput system. The most massive source of incoming energy is solar radiation, with geothermal and tidal energy completing the circle. All of these forms of energy are converted to heat and re-radiated into space. In 2010, scientists at the National Center for Atmospheric Research in Boulder, Colorado publicized a study taken from satellite observations which stated there were certain variances between Earth’s heat and ocean heating. What they found was “missing energy” in our planet’s system. Why did this energy seem to be disappearing? The research group began wondering if perhaps there was a problem with the method of recording energy as absorbed from the Sun and its emission back to space.
This was a question that needed an answer. Enter an international team of atmospheric scientists and oceanographers, led by Norman Loeb of NASA’s Langley Research Center in Hampton, Virginia, and including Graeme Stephens of NASA’s Jet Propulsion Laboratory in Pasadena, California. It was their mission to account for the missing energy. Armed with 10 years of data from NASA Langley’s orbiting Clouds and the Earth’s Radiant Energy System Experiment (CERES) instruments, the team set out to record the radiation balance located at the apex of Earth’s atmosphere and how it changed with time. Supplied with the CERES data, they then combined it with estimates of oceanic heat content as recorded by three separate sensors. Their findings showed that both satellite and physical measurements of the ocean’s energy agreed with one another once observational uncertainties were added to the equation. Their work was summarized in a NASA-led study published January 22 in the journal Nature Geosciences,
“One of the things we wanted to do was a more rigorous analysis of the uncertainties. When we did that, we found the conclusion of missing energy in the system isn’t really supported by the data.” said Loeb. “Our data shows that Earth has been accumulating heat in the ocean at a rate of half a watt per square meter (10.8 square feet), with no sign of a decline. This extra energy will eventually find its way back into the atmosphere and increase temperatures on Earth.”
For the most part, scientists concur that around 90% of extra heat created by the greenhouse gas effect is being stored in Earth’s oceans. If it follows the laws of thermodynamics and is released back into the atmosphere, “a half-watt per square meter accumulation of heat could increase global temperatures by 0.3 or more degrees centigrade or 0.54 degree Fahrenheit”. As Loeb explained, these observations show the need to employ several different measuring systems over time and the findings underline the imperative need to continually update how Earth’s energy flows are recorded.
The newly published work came from the science team at the National Center for Atmospheric Research and other authors of the paper are from the University of Hawaii, the Pacific Marine Environmental Laboratory in Seattle, the University of Reading United Kingdom and the University of Miami. Their study mapped inconsistencies between satellite information on Earth’s heat balance between the years of 2004 and 2009 and included information on the rate of oceanic heating taken from the upper 700 meters of the surface. They said the inconsistencies were evidence of “missing energy.”
The LABOCA camera on the ESO-operated 12-metre Atacama Pathfinder Experiment (APEX) telescope reveals distant galaxies undergoing the most intense type of star formation activity known, called a starburst. This image shows these distant galaxies, found in a region of sky known as the Extended Chandra Deep Field South, in the constellation of Fornax (The Furnace). The galaxies seen by LABOCA are shown in red, overlaid on an infrared view of the region as seen by the IRAC camera on the Spitzer Space Telescope. Credit: ESO, APEX (MPIfR/ESO/OSO), A. Weiss et al., NASA Spitzer Science Center
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Located on the Chajnantor plateau in the foothills of the Chilean Andes, ESO’s APEX telescope has been busy looking into deep, deep space. Recently a group of astronomers released their findings regarding massive galaxies in connection with extreme times of star formation in the early Universe. What they found was a sharp cut-off point in stellar creation, leaving “massive – but passive – galaxies” filled with mature stars. What could cause such a scenario? Try the materialization of a supermassive black hole…
By integrating data taken with the LABOCA camera on the ESO-operated 12-metre Atacama Pathfinder Experiment (APEX) telescope with measurements made with ESO’s Very Large Telescope, NASA’s Spitzer Space Telescope and other facilities, astronomers were able to observe the relationship of bright, distant galaxies where they form into clusters. They found that the density of the population plays a major role – the tighter the grouping, the more massive the dark matter halo. These findings are the considered the most accurate made so far for this galaxy type.
Located about 10 billion light years away, these submillimetre galaxies were once home to starburst events – a time of intense formation. By obtaining estimations of dark matter halos and combining that information with computer modeling, scientists are able to hypothesize how the halos expanding with time. Eventually these once active galaxies settled down to form giant ellipticals – the most massive type known.
“This is the first time that we’ve been able to show this clear link between the most energetic starbursting galaxies in the early Universe, and the most massive galaxies in the present day,” says team leader Ryan Hickox of Dartmouth College, USA and Durham University, UK.
However, that’s not all the new observations have uncovered. Right now there’s speculation the starburst activity may have only lasted around 100 million years. While this is a very short period of cosmological time, this massive galactic function was once capable of producing double the amount of stars. Why it should end so suddenly is a puzzle that astronomers are eager to understand.
“We know that massive elliptical galaxies stopped producing stars rather suddenly a long time ago, and are now passive. And scientists are wondering what could possibly be powerful enough to shut down an entire galaxy’s starburst,” says team member Julie Wardlow of the University of California at Irvine, USA and Durham University, UK.
Right now the team’s findings are offering up a new solution. Perhaps at one point in cosmic history, starburst galaxies may have clustered together similar to quasars… locating themselves in the same dark matter halos. As one of the most kinetic forces in our Universe, quasars release intense radiation which is reasoned to be fostered by central black holes. This new evidence suggests intense starburst activity also empowers the quasar by supplying copious amounts of material to the black hole. In response, the quasar then releases a surge of energy which could eradicate the galaxy’s leftover gases. Without this elemental fuel, stars can no longer form and the galaxy growth comes to a halt.
“In short, the galaxies’ glory days of intense star formation also doom them by feeding the giant black hole at their centre, which then rapidly blows away or destroys the star-forming clouds,” explains team member David Alexander from Durham University, UK.
Artist's Concept of New Planetary Systems - Credit: NASA
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Eleven ball in the side pocket. Whack! And another 26 planets are discovered! NASA just announced the latest tally and the new discoveries come close to doubling the amount of verified planets and tripling the number of stars which are confirmed to have more than one transiting planet. It’s just another score for understanding how planets came to be… planets which run the gambit from about one and half times the size of Earth up to the size of Jupiter. Of these, fifteen are judged to be between the size of Earth and Neptune – while more observations will reveal their structure. The new bodies orbit the parent star between 6 and 143 days and all are closer than our Sun/Venus distance.
“Prior to the Kepler mission, we knew of perhaps 500 exoplanets across the whole sky,” said Doug Hudgins, Kepler program scientist at NASA Headquarters in Washington. “Now, in just two years staring at a patch of sky not much bigger than your fist, Kepler has discovered more than 60 planets and more than 2,300 planet candidates. This tells us that our galaxy is positively loaded with planets of all sizes and orbits.”
Kepler is a busy-body. It monitors the brightness changes in more than 150,000 stars. Through repeated measurements, it is able to pick out minute magnitude fluctuations which occur as a planet passes between us, Kepler and the parent sun. The newly documented solar systems are host to between two and five closely situated transiting bodies. In such cramped systems, the gravitational interaction between the orbiting members means some are accelerated – and others decelerated – in their tracks. Faster orbital speeds account for changes in orbital periods… Changes that the Kepler mission documents as Transit Timing Variations (TTVs). For planetary systems possessing TTVs, no extreme study with ground-based telescopes is required to verify their existence and the technique allows Kepler to validate the presence of planetary systems around further and fainter stars.
What’s been found? Five of the systems documented as Kepler-25, Kepler-27, Kepler-30, Kepler-31 and Kepler-33, are home to a set of planets whose orbits double each other. The outer body orbits twice for every inner body orbit. Four of the systems, Kepler-23, Kepler-24, Kepler-28 and Kepler-32, are home to a pairing where the outer planet circles the star twice for every three times the inner planet orbits.
“These configurations help to amplify the gravitational interactions between the planets, similar to how my sons kick their legs on a swing at the right time to go higher,” said Jason Steffen, the Brinson postdoctoral fellow at Fermilab Center for Particle Astrophysics in Batavia, Ill., and lead author of a paper confirming four of the systems.
And now for the game ball… Kepler-33 had the most planets of all. With a parent star older and more massive than Sol, the system gives rise to five planets whose sizes run between one and a half to five times the size of Earth. But, this is one crowded grouping. All of the planets orbiting this star are closer than Mercury is to our Sun! Thanks to stellar properties, Kepler is able to distinguish planets like these. The drop in the sun’s brightness and the length of time it takes for the planet to transit all play a role in determining presence. With similar signatures verified around the same star, chances of false readings are unlikely.
“The approach used to verify the Kepler-33 planets shows the overall reliability is quite high,” said Jack Lissauer, planetary scientist at NASA Ames Research Center at Moffett Field, Calif., and lead author of the paper on Kepler-33. “This is a validation by multiplicity.”
A rendering of the Cluster satellite, designed to measure electric fields, which Andre and Cully used to detect low-energy ions high above the Earth. (Credit: European Space Agency)
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Thousands of miles above Earth, space weather rules. Here storms of high-energy particles mix the atmosphere, create auroras, challenge satellites and even cause disturbances with electric grids and electronic devices below. It’s a seemingly empty and lonely place – one where a mystery called “cold plasma” has been found in abundance and may well have implications with our connection to the Sun. While it has remained virtually hidden, Swedish researchers have created a new method to measure these cold, charged ions. With evidence of more there than once thought, these new findings may very well give us clues as to what’s happening around other planets and their natural satellites.
“The more you look for low-energy ions, the more you find,” said Mats Andre, a professor of space physics at the Swedish Institute of Space Physics in Uppsala, Sweden, and leader of the research team whose findings have been accepted for publication in Geophysical Research Letters, a journal of the American Geophysical Union. “We didn’t know how much was out there. It’s more than even I thought.”
Where does this enigma originate? The low-energy ions begin in the upper portion of our atmosphere called the ionosphere. Here solar energy can strip electrons from molecules, leaving atoms such as oxygen and hydrogen with a positive charge. However, physically finding these ions has been problematic. While researchers knew they existed at altitudes of about 100 kilometers (60 miles), Andre and colleague Chris Cully set their sites higher – at between 20,000 and 100,000 km (12,400 to 60,000 mi). At the edge, the amount of cold ions varies between 50 to 70%… making up most of the mass of space.
However, that’s not the only place cold plasma has been found. According to the research satellite data and calculations, certain high-altitude zones harbor low-energy ions continuously. As far fetched as it may sound, the team has also detected them at altitudes of 100,000 km! According to Andre, discovering so many relatively cool ions in these regions is surprising because there’s so much energy hitting the Earth’s high altitudes from the solar wind – a hot plasma about 1,000 times hotter than what Andre considers cold. Just how cold? “The low-energy ions have an energy that would correspond to about 500,000 degrees Celsius (about one million degrees Fahrenheit) at typical gas densities found on Earth. But because the density of the ions in space is so low, satellites and spacecraft can orbit without bursting into flames.”
A scientist examines one of the European Space Agency's four Cluster satellites, used in a recent Geophysical Research Letters study to measure low-energy ions. (Credit: European Space Agency)
Pinpointing these low-energy ions and measuring how much material is leaving our atmosphere has been an elusive task. Andre’s workshop is a satellite and one of the four European Space Agency CLUSTER spacecraft. It houses a detector created from a fine wire that measures the electronic field between them during satellite rotation. However, when the data was collected, the researchers found a pair of mysteries – strong electric fields in unexpected areas of space and electric fields that didn’t fluctuate evenly.
“To a scientist, it looked pretty ugly,” Andre said. “We tried to figure out what was wrong with the instrument. Then we realized there’s nothing wrong with the instrument.” What they found opened their eyes. Cold plasma was changing the arrangement of the electrical fields surrounding the satellite. This made them realize they could utilize their field measurements to validate the presence of cold plasma. “It’s a clever way of turning the limitations of a spacecraft-based detector into assets,” said Thomas Moore, senior project scientist for NASA’s Magnetospheric Multiscale mission at the Goddard Space Flight Center in Greenbelt, Maryland. He was not involved in the new research.
Through these new techniques, science can measure and map Earth’s cold plasma envelope – and learn more about how both hot and cold plasma change during extreme space weather conditions. This research points towards a better understanding of atmospheres other than our own, too. Currently the new measurements show about a kilogram (two pounds) of cold plasma escapes from Earth’s atmosphere every second, By having a solid figure as a basis for rate of loss, scientists may be able model what became of Mars’ atmosphere – or explain the atmosphere around other planets and moons. It can also aid in more accurate space weather forecasting – even if it doesn’t directly influence the environment itself. It is a key player, even if it doesn’t cause the damage itself. “You may want to know where the low-pressure area is, to predict a storm,” Andre noted.
Modernizing space weather forecasting to where it is similar to ordinary weather forecasting, was “not even remotely possible if you’re missing most of your plasma,” Moore, with NASA, said. Now, with a way to measure cold plasma, the goal of high-quality forecasts is one step closer. “It is stuff we couldn’t see and couldn’t detect, and then suddenly we could measure it,” Moore said of the low-energy ions. “Now you can actually study it and see if it agrees with the theories.”
The StarLab rocket hangs beneath the wing of a Starfighter jet recently during taxi testing. The rocket, about the size of an air-to-air missile, was built by the 4Frontiers company to launch experiments into space. Photo credit: NASA/Gianni M. Woods
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Move over, Buck Rogers… The time has come for StarFighters, Inc.! Just a few days ago, the exclusive contingent’s final forces assembled at NASA’s Kennedy Space Center in Florida, ready to go on duty with a private company which will deploy them for research and microgravity training. Purchased from the Italian Air Force, these five new aircraft began their life as F-104 fighters, but as part of StarFighters, Inc. will pursue different venues as members of a nine plane squadron… One with a more peaceful goal.
According to owner Rick Svetkoff, this means there will always be aircraft available to fly for not only a variety of customers, but a variety of missions as well. The company will also be able to offer an additional aircraft on a single mission to serve as a “chase plane” to photographically document experiments.
“Now we’re in a position where we can really start operations,” Svetkoff said. “Before, we couldn’t do a lot of things we wanted to do.”
Under an agreement with Kennedy Space Center, StarFighters Inc. calls a hangar at the Shuttle Landing Facility home. The company’s goal is to serve as a research and development platform – one whose repertoire expands across a variety of venues such as “evaluating rocket and spacecraft in high-stress environments including high-acceleration and microgravity”. At this time, Embry-Riddle University and Space Florida are already on-board with the team.
One of the existing fleet of F-104 Starfighters is joined by the newer, but not yet assembled, jets the company just bought from Italy. Photo credit: NASA/Frankie Martin
These are not just any planes, however. The F-104s are capable of reaching an altitude of around 70,000 feet and speeds exceeding Mach 2. This means they can be engaged to launch small satellites into space and the 19-foot-long, 900-pound rocket lodged under the wings has already been tested. Additional test flights with the rocket will be carried out in February and the first launch is expected to happen during this summer. These launches are designed to take less bulky experiments into space, but not orbit. Once completed, the rocket will then parachute down to Earth and be retrieved from the ocean for recycling. According to Svetkoff, the company expects to use StarFighters to launch around 100 suborbital missions annually and in less than a year should begin launching nanosatellites with a similar method.
Starfighters pilot and owner Rick Svetkoff in the cockpit of one of the Starfighters already in service with the company. Photo credit: NASA/Gianni M. Woods
As futuristic as its name sounds, the F-104 Starfighter isn’t new. It’s a decades-old, supersonic aircraft which originally served during the Cold War to intercept Soviet aircraft. It was once dubbed “the missile with a man in it” because of its fast speeds and trim design. It was the concept developed by Lockheed Martin’s Kelly Johnson – who also designed the SR-71 and U-2. Some 50 years ago, the Starfighter also served NASA by helping to train astronauts in microgravity and sharpening their skills in high-speed flight.
“Anything an F-16 or an F-18 can do, we can do with this aircraft, performance-wise,” said Svetkoff who also commented that research and development flights could add another 100 missions to the StarFighter’s log annually.
A truck delivers an F-104 Starfighter to the hangar at NASA's Kennedy Space Center in Florida where Starfighters Inc. operates. Photo credit: NASA/Frankie Martin
It’s a great idea that isn’t going to end with just some experiments, though. As we progress and private companies realize the opportunities of working with NASA and launching humans into space, StarFighters can be used to train for microgravity and other implications – just as they have in the past. For now, the focus is on getting the planes cleaned and ready for work. This means careful disassembly of engines and other parts, cleaning and reassembly. The StarFighters will also get updated, too. There are new avionics packages available which will add digital displays. It may take as long as three months to complete the first, but the entire fleet should be ready in about six months.
“This shows a serious commitment,” concludes Svetkoff.
