SETI, the Search for Extraterrestrial Intelligence suffered a big blow in April of this year when the primary alien search engine –the Allen Telescope Array (ATA) in northern California — was put into “hibernation” due to lack of funds. But now you can help get the ATA back online through a crowdsourcing effort called SETIstars. Similar to fundraising efforts like KickStarter, SETIstars is working to raise enough money to bring the telescope array online again and provide operating costs for at least one year. The goal is to raise $200,000.
As of this writing, nearly $30,000 has been raised already.
While the ATA is not the only radio telescope that can be used for SETI searches, it was the observatory that was primarily used for that task. The funding crisis occured when state and the National Science Foundation contributions were significantly cut.
SETIstars is an initiative by the SETI Institute to rally support from the community to help fund the SETI Institute’s operations and that of the Allen Telescope Array. SETIstars has clearly defined fundraising goals, and will recognize supporters and contributors to the SETI Institute — both financial and non-financial.
“We are starting with a simple site with a clear mandate: raise funds from the community to help bring the ATA back on line,” says the SETIstars website. “But this is just the beginning…Bringing the ATA back online is a critical first step. However, sustaining operations is also of vital importance. SETIstars will be a rallying point for future community engagement and fundraising efforts.”
Here’s your chance to allow SETI scientists to start listening for signals from space again, especially in the region in space where Kepler has found a boatload of exoplanets. Your donations are tax free (in the US) since SETI is a nonprofit institution. International donors should contact their government for information on tax deductions for charitable gifts to U.S. based charities.
Several teams of astronomers are taking advantage of a rare double event this week to learn more about the atmosphere and makeup of Pluto and its moons. The dwarf planet will occult, or pass in front of two different stars this week. One of the best viewing sites for these two events is in Hawaii, and eclipse-chaser Dr. Jay Pasachoff is there to record both events. “To see those occultations, we have to be in a particular set of places on Earth, those over which the shadow of the object in starlight passes,” Pasachoff wrote in a guest post on the Planet Hunters blog. “Since the stars are so far away, their light is essentially parallel and the shadows of the objects on Earth are the same as the sizes of the objects.”
If all goes well, we will know a lot more about the Pluto system, Pasachoff said.
Map of where the occultation would be visible on June 22-23, 2011.
Last night, June 22/23, both Pluto and its moon Charon occulted a magnitude 14.4 star, with each occultation lasting a minute or so and separated from each other by 12 minutes. “The event is particularly exciting because if we capture both Pluto and Charon nearly simultaneously, we can find out about the system’s internal orbits with higher precision than before, perhaps allowing a refinement of the center of mass and thus the masses and densities of each object,” Pasachoff said.
Also, the first deployment for an occultation of the NASA/German SOFIA observatory took place last night to view the Pluto occultation, flying at an altitude of 43,000 feet off the west coast of Central America.
“The scientific goal is to catch the ‘central flash,’ which conveys vital information about conditions in Pluto’s global atmosphere,” wrote American Astronomical Society press officer Rick Fienberg on Twitter. Fienberg was part of the press corps that was accompanying the flight.
On Sunday/Monday night, June 26/27, Pluto will occult a different star, and over a much narrower path, its small moon Hydra might also occult another star.
Pasachoff said that the most recent predictions for last night’s occulations shifted the prediction south, so that Hawaii is slightly off the main predicted path, to its north. But other teams are in Cairns, Australia, to see if it goes that far south.
For the June 26/27 event (June 27 UT but June 26 in Hawaii), the star is magnitude 13.6. “That is a couple of magnitudes brighter than most of the stars we have observed being occulted,” Pasachoff said, “so the data would be particularly low-noise. In addition to the occultation of Pluto itself, whose southern limit is predicted to pass through the Hawaiian islands, the tiny Pluto moon Hydra is to be occulted, though that narrow path’s prediction now passes north of the Hawaiian islands. We have arranged for telescopes in Yunnan, China, in Japan, Taiwan, and Thailand to observe with us, and MIT’s Matt Lockhart is en route to Yunnan with one of our POETS (Portable Occultation, Eclipse, and Transit System) cameras. We have Australian sites still observing as well, just in case the actual path is hundreds of kilometers south of the predictions.”
Earlier occultations by Pluto studied by Pasachoff and his colleagues showed that Pluto’s atmosphere was warming and that the atmosphere would probably remain warm enough by 2015 for the New Horizons spacecraft to detect and study it with its on-board instruments, and was part of the incentive for the mission to launch when it did.
We’ll try to provide an update of the events when details become available.
You can follow Universe Today senior editor Nancy Atkinson on Twitter: @Nancy_A. Follow Universe Today for the latest space and astronomy news on Twitter @universetoday and on Facebook.
Check out this way cool time-lapse movie of NASA’s Curiosity Mars rover as its being packed up for her trip to Florida.
The video covers a 4 day period from June 13 to 17 and is condensed to just 1 minute. Watch the JPL engineers and technicians prepare Curiosity and the descent stage for shipping to the Kennedy Space Center in Florida and place it inside a large protective shipping container. Continue reading “Packing a Mars Rover for the Trip to Florida”
An X-Wing fighter in space? Actually the ATV2 (Johannes Kepler) as it departs the ISS in 2011. Credit: NASA/Ron Garan
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What an amazing image! The ATV-2 Johannes Kepler looks like an X-Wing fighter from Star Wars as it departed from the International Space Station. Astronaut Ron Garan posted the image on his Twitpic page, asking viewers if they thought the spacecraft looked like the fictional fighter jets of the Alliance.
The ATV-2 left the ISS and entered Earth’s atmosphere on June 21. The spacecraft had a “blackbox” on board, a Re-Entry Breakup Recorder (REBR) to monitor temperature, acceleration, rotation rate, and other data as it tumbled and disintegrated through the atmosphere. The data was sent down via a “phone call” to an Iridium satellite to help scientists better understand the physics of what happens to a spacecraft when it breaks up on re-entry.
So, enjoy one last beautiful look at the ATV-2 in this stunning image.
You can follow Universe Today senior editor Nancy Atkinson on Twitter: @Nancy_A. Follow Universe Today for the latest space and astronomy news on Twitter @universetoday and on Facebook.
Enceladus' signature ice geysers in action. NASA / JPL / SSI
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Researchers on the Cassini mission team have identified large salt grains in the plumes emanating from Saturn’s icy satellite Enceladus, making an even stronger case for the existence of a salty liquid ocean beneath the moon’s frozen surface.
Cassini first discovered the jets of water ice particles in 2005; since then scientists have been trying to learn more about how they behave, what they are made of and – most importantly – where they are coming from. The running theory is that Enceladus has a liquid subsurface ocean of as-of-yet undetermined depth and volume, and pressure from the rock and ice layers above combined with heat from within force the water up through surface cracks near the moon’s south pole. When this water reaches the surface it instantly freezes, sending plumes of ice particles hundreds of miles into space.
Enceladus inside the E ring
Much of the ice ends up in orbit around Saturn, creating the hazy E ring in which Enceladus resides.
Although the discovery of the plumes initially came as a surprise, it’s the growing possibility of liquid water that’s really intriguing – especially that far out in the Solar System and on a little 504-km-wide moon barely the width of Arizona. What’s keeping Enceladus’ water from freezing as hard as rock? It could be tidal forces from Saturn, it could be internal heat from its core, a combination of both – or something else entirely… astronomers are still hard at work on this mystery.
Now, using data obtained from flybys in 2008 and 2009 during which Cassini flew directly through the plumes, researchers have found that the particles in the jets closest to the moon contain large sodium- and potassium-rich salt grains. This is the best evidence yet of the existence of liquid salt water inside Enceladus – a salty underground ocean.
“There currently is no plausible way to produce a steady outflow of salt-rich grains from solid ice across all the tiger stripes other than salt water under Enceladus’s icy surface.”
– Frank Postberg, Cassini team scientist, University of Heidelberg, Germany
Looking down into a jetting "tiger stripe"
If there indeed is a reservoir of liquid water, it must be pretty extensive since the numerous plumes are constantly spraying water vapor at a rate of 200 kg (400 pounds) every second – and at several times the speed of sound! The plumes are ejected from points within long, deep fissures that slash across Enceladus’ south pole, dubbed “tiger stripes”.
Recently the tiger stripe region has also been found to be emanating a surprising amount of heat, even further supporting a liquid water interior – as well as an internal source of energy. And where there’s liquid water, heat energy and organic chemicals – all of which seem to exist on Enceladus – there’s also a case for the existence of life.
“This finding is a crucial new piece of evidence showing that environmental conditions favorable to the emergence of life can be sustained on icy bodies orbiting gas giant planets.”
– Nicolas Altobelli, ESA project scientist for Cassini
Enceladus has intrigued scientists for many years, and every time Cassini takes a closer look some new bit of information is revealed… we can only imagine what other secrets this little world may hold. Thankfully Cassini is going strong and more than happy to keep on investigating!
“Without an orbiter like Cassini to fly close to Saturn and its moons — to taste salt and feel the bombardment of ice grains — scientists would never have known how interesting these outer solar system worlds are.”
– Linda Spilker, Cassini project scientist at JPL
The findings were published in this week’s issue of the journal Nature.
Image credits: NASA / JPL / Space Science Institute
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Jason Major is a graphic designer, photo enthusiast and space blogger. Visit his website Lights in the Dark and follow him on Twitter @JPMajor or on Facebook for the most up-to-date astronomy awesomeness!
This X-ray image of Cygnus X-1 was taken by a balloon-borne telescope, the High Energy Replicated Optics (HERO) project. NASA image.
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Discovered in 1964 during a rocket flight, Cygnus X-1 holds the record for being the strongest X-ray source seen from Earth. The blue supergiant star designated as HDE 226868 is just part of this high-mass X-ray binary system… the other is a black hole.
“We present a detailed study of the X-ray dust scattering halo of the black hole candidate based on two Chandra HETGS observations. Using 18 different dust models, including one modified by us (dubbed XLNW), we probe the interstellar medium between us and this source.” says Jingen Xiang, et al. “A consistent description of the cloud properties along the line of sight that describes at the same time the halo radial profile, the halo lightcurves, and the column density from source spectroscopy is best achieved with a small subset of these models… The remainder of the dust along the line of sight is close to the black hole binary.”
Located about 6,000 light years from Earth as measured by the Hipparcos satellite (but this value has a relatively high degree of uncertainty), Cygnus X-1 has been the topic for a huge amount of astronomical studies for nearly 50 years. We’re aware the blue supergiant variable star orbits its unseen companion at roughly 1/5 the distance of the Sun to the Earth (0.2 AU), and we surmised that stellar wind accounted for the accretion disk around the X-ray source. We are also aware of a pair of jets spewing material into interstellar space. Deep inside, superheated materials are sending out copious amounts of X-rays, but what else lay beyond? Can we separate star from event horizon with accuracy?
“We report a direct and accurate measurement of the distance to the X-ray binary Cygnus X-1, which contains the first black hole to be discovered. The distance of 1.86(-0.11,+0.12) kpc was obtained from a trigonometric parallax measurement using the Very Long Baseline Array. The position measurements are also sensitive to the 5.6 d binary orbit and we determine the orbit to be clockwise on the sky.” says Mark J. Reid, et al. “We also measured the proper motion of Cygnus X-1 which, when coupled to the distance and Doppler shift, gives the three-dimensional space motion of the system. When corrected for differential Galactic rotation, the non-circular (peculiar) motion of the binary is only about 21 km/s, indicating that the binary did not experience a large “kick” at formation.”
If you don’t think this is exciting news, then think again. “The compact primary in the X-ray binary Cygnus X-1 was the first black hole to be established via dynamical observations.” says Lijun Gou. “We have recently determined accurate values for its mass and distance, and for the orbital inclination angle of the binary. Building on these results, which are based on our favored (asynchronous) dynamical model, we have measured the radius of the inner edge of the black hole’s accretion disk by fitting its thermal continuum spectrum to a fully relativistic model of a thin accretion disk.”
Determining the spin rate has been high on the list of observations – and difficult because it changed states periodically. Only when it is in a soft spectral state can accurate measurements be taken. Oddly enough, for all the countless observations taken of Cygnus X-1 over the years, it has never been caught in a thermally dominant state. To that end, the black hole spin is measured by estimating the inner radius of the accretion disk.
“Our results take into account all significant sources of observational and model-parameter uncertainties, which are dominated by the uncertainties in black hole mass, orbital inclination angle and distance.” says the team. “The uncertainties introduced by the thin-disk model we employ are particularly small in this case, given the disk’s low luminosity.”
A Hubble Space Telescope color image of a small portion of the cluster only 0.63 light-years across reveals eight white dwarf stars (inside blue circles) among the cluster's much brighter population of yellow sun-like stars and cooler red dwarf stars. (Credit: Harvey Richer (University of British Columbia, Vancouver, Canada) and NASA)
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With no more volume than could be contained within a teaspoon, the material that makes up a white dwarf star weighs tons. Smaller than the diameter of Earth, and a direct family member of stars like our own Sol, these stellar gnomes could predict our eventual fate.
Using data from the Hubble Space Telescope, Nathan Dickinson, a postgraduate student in the University’s Department of Physics and Astronomy, is hard at work analyzing chemical compositions of white dwarf stars for his PhD. Unlike many students interested in “heavy metal”, Dickinson is more interested in “heavy elements”. The older, more cool models could contain elements such as oxygen, nitrogen, silicon… while the hot youngsters show heavy elements like calcium and magnesium. These weighty basics occur at extreme heat and sometimes, even to excess. The cremation generation?
“Understanding whether the extra material in hot white dwarfs comes from torn up planets is important,” emphasizes Dickinson. “It can give us an idea of how these ancient planetary systems evolve as the star ages, so we get a fuller picture of how solar systems die. However, they sometimes exhibit more of this material than is expected, which raises the question of whether this extra material also came from planets or whether it originated elsewhere, perhaps in clouds around the star.”
Past research has shown that anywhere from 1 to 3% of white dwarf stars can be contaminated by an influx of materials from closely orbiting dust clouds. What makes up these clouds? It could be rocky debris like asteroids. Held within the Roche Limit, these planetoids are mulched by gravitational tides – just like Saturn’s ring system.
“Working at the forefront of this scientific area is extremely exciting,” says Dickinson. “I find being one of a relatively small community of people in the world to work on this particular area amazing. This work is helping to shape our understanding of how most stars end their lives, how solar systems die, how the environment around these ancient stars behaves and what will ultimately happen to the vast majority of stars in the galaxy.”
Ground-based images of three different classified satellites: the X-37B, USA-186 Keyhole, and the LaCrosse 3. Credit: Thierry Legault and Emmanuel Rietsch
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Shhhh! Don’t tell anyone, but we’ve got pictures….. ground-based pictures of secret spy satellites in Earth orbit. We’re not revealing our sources, but … oh wait, I guess we might as well tell you. Even if we didn’t reveal our source, you’d probably guess that astrophotographer extraordinaire Thierry Legault — who has been sharing his wonderfully detailed ground-based images of the space shuttle and International Space Station with Universe Today – has been working on capturing other satellites in orbit as well. Legault and his partner in imaging crime, Emmanuel Rietsch have tackled the difficult task of tracking down spy satellites and then tracking them with a telescope. For imaging the shuttle and ISS, they developed their own design of a motorized mount outfitted with a computer program so it can slowly and precisely rotate in order to track and follow an object in Earth orbit with a telescope and video camera. Now they are able to image even smaller objects.
Thierry Legault with his customized satellite tracking system. Photo courtesy Thierry Legault.
Since October 2010, Legault has been using the autoguided mount, with the help of a DMK 31AF03 Firewire video camera mounted on the finder (FL 200 mm) and of the software Videos Sky, created by Rietsch, and then modified by Reitsch and Legault for fast tracking with the Takahashi EM400 mount.
The X-37B spaceplane now in orbit is the second of the two Orbital Test Vehicles launched by the US Air Force, launched on March 5, 2011. Reportedly, it will conduct experiments and tests for close to nine months and then autonomously de-orbit and land. Legault and Rietsch were able to image the spaceplane in late May of this year with fairly good results.
“I tried to get help to identify the real orientation of X-37B,” Legault told Universe Today via Skype today, “but on the contrary of the Keyhole and Lacrosse satellites, it’s not easy considering its complex shape with several wings.”
And the Air Force isn’t telling.
“Keyhole-class” (KH) reconnaissance satellites have been used for more than 30 years and are typically used to take overhead photos for military missions. Some of the keyhole satellites resemble the Hubble Space Telescope, but instead of looking out into space, it looks back at Earth. A similar type of spy satellites are the Lacrosse satellites, which are radar-imaging satellites.
But even with the tracking system, getting images of small satellites is not easy. “Despite this performing tracking system and hours of training on airplanes passing in the sky, keeping the space ship inside a sensor of a few millimeters at a focal length of 5000 mm and a speed over 1°/s needs a lot of concentration and training,” said Legault on his website.
The autoguiding and acquisition are done via a laptop with a double hard drive (one of which is a Solid State Drive – made with flash memory), enabling the precision of tracking of about one arc minute.
For security reasons, the sighting times for spy satellites are not published on an official website like NASA does for the shuttle and ISS. But with a bit of digging, Legault said others can try their luck at trying to spot these secret satellites.
“Orbital data are in the Calsky database,” Legault told UT, “therefore their passages are forecast as for the ISS. Generally, orbits are determined by amateurs, some of them are specialized in this activity, especially Kevin Fetter (and data are exchanged on the Seesat mailing list, owned by Ted Molczan).”
Legault is well-known for his images of the shuttle and ISS transiting the sun, but he said the accuracy of orbital data for the spy satellites is not sufficient for capturing a solar transit – and besides, these satellites are much smaller than the ISS and would appear as a small dark dot, at best.
“But for nighttime passages the data is sufficient,” Legault said. “Generally they are not visible with the naked eye or barely (except during flares), but they are easily visible with a finder.”
You can follow Universe Today senior editor Nancy Atkinson on Twitter: @Nancy_A. Follow Universe Today for the latest space and astronomy news on Twitter @universetoday and on Facebook.
Bluer galaxies are actively “awake” and forming stars, while redder galaxies have shut down and are “asleep.” (Image: NASA, ESA, S. Beckwith (STScI) and the HUDF team)
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It’s a well known fact that galaxies come in two types – either actively forming stars or not. In simplistic terms, that means they are either awake or asleep. But now scientists are looking back twelve billion light years across time to find the same holds just as true then as it does now. As a matter of fact, galaxies may have been behaving this way for around 85% of the history of the Universe.
“The fact that we see such young galaxies in the distant universe that have already shut off is remarkable,” said Kate Whitaker, a Yale University graduate student and lead author of the paper, which is published in the June 20 online edition of the Astrophysical Journal.
So, without poking the sleeping dragon, just how did the astronomers make their determinations? Try with the use of a 4-meter Kitt Peak telescope in Arizona and a special set of filters developed by Whitaker and her team. Just like all astronomy filters, this new breed is selective to certain bandpasses, or wavelengths, of light. These new filter sets were then used on 40,000 galaxies over a 75 night period and the data collected and examined. The end product was the deepest and most comprehensive of its kind so far. Active, awake galaxies appear more blue, while the sleepy-heads appear red. Believe it or not, when it comes to the cosmic bedroom there’s more activity than previously thought.
“We don’t see many galaxies in the in-between state,” said Pieter van Dokkum, a Yale astronomer and another author of the paper. “This discovery shows how quickly galaxies go from one state to the other, from actively forming stars to shutting off.”
Whether the dozing galaxies have completely shut down remains an open question, Whitaker said. However, the new study suggests the active galaxies are forming stars at rates about 50 times greater than their somnambulistic counterparts. “Next, we hope to determine whether galaxies go back and forth between waking and sleeping or whether they fall asleep and never wake up again,” van Dokkum said. “We’re also interested in how long it takes galaxies to fall asleep, and whether we can catch one in the act of dozing off.”
Pass the Red Bull… and sing the blues! “Are you sleeping? Can you hear me? Do you know if I am by your side? Does it matter? If you hear me? When the mornin’ comes I’ll be there by your side… There was a time, we had a time. There was a time we had time…”
For every astronomer everywhere – and even naturalists – the need to preserve dark skies has been an issue tackled by the International Dark Skies Association for over two decades. It’s more than just asking your neighbor to turn off their porch light while you’re observing. It’s about light pollution as a whole – from government to community lighting. In the past the IDA has relied on education, but now things could be getting a whole lot better.
“IDA and the Illuminating Engineering Society (IES) proudly announce public release of the Model Lighting Ordinance (MLO) as a valuable guide for environmentally responsible outdoor lighting in North America.” says the organization. “Developed jointly by the IDA and the IES over a period of seven years, the IDA/IES partnership will encourage broad adoption of comprehensive outdoor lighting ordinances without devoting extensive staff time and resources to their development.”
In a time of budget cuts and pressure on volunteer time, such programs like the MLO are absolutely invaluable. This guide will enable communities to make responsible decisions about outdoor lighting standards… effectively reducing glare, light trespass, and skyglow. Studies have shown these three culprits of light pollution wreak havoc on more than just astronomy – it affects our own human biorhythms, wildlife and more. By having a standard that’s easy and cost effective to follow, things can be changed.
“The MLO offers several innovations to outdoor lighting regulation, including the use of five lighting zones to classify land use with appropriate lighting levels for each. Zones range from LZ0, designed for pristine natural environments and limited outdoor lighting, to LZ4, for limited application in areas of extensive development in the largest cities. The second innovation limits the amount of light used for each property.” says the group. “Third, the MLO uses the IES’s new TM-15 -11 “BUG” (Backlight, Uplight and Glare) classification of outdoor lighting fixtures to ensure that only well-shielded fixtures are used. No uplight for area and street lighting is allowed in any zone. The MLO will be revised on a regular basis to include new information, feedback from municipalities using it and changes to IES standards.”
Will these new guidelines be adopted by government and industry? You might be surprised at just how well concepts of this type can be accepted when you can show how they are not only cost effective, but energy saving as well. Not everyone around the world reacts in a negative way when asked to cut lighting – especially when they realize a group is tackling major concerns such as security and safety.
Bob Parks, executive director of IDA, hopes for widespread application. “The MLO will give communities the tool they need to control outdoor lighting and the assurance that the outcome will meet the international standards developed by the IES,” states Parks. “The MLO will accelerate adoption of quality outdoor lighting practices in municipalities of all sizes and show planners how to improve the quality of outdoor lighting while saving energy and reducing operating cost.”
Robert Horner, director of public policy for the IES, expresses similar expectations, stating, “The IES is proud to have produced, in partnership with the IDA, the first Model Lighting Ordnance. This will give states and municipalities the ability to enact effective outdoor lighting legislation and codes, while maintaining the necessary lighting quality for a safe and secure lighted environment and meeting all relevant IES standards and practices.”
In the meantime, get involved with your community and the IDA. Our dark skies future starts with you…
