Early Galaxy Found from the Cosmic ‘Dark Ages’

In the big image at left, the many galaxies of a massive cluster called MACS J1149+2223 dominate the scene. Gravitational lensing by the giant cluster brightened the light from the newfound galaxy, known as MACS 1149-JD, some 15 times. At upper right, a partial zoom-in shows MACS 1149-JD in more detail, and a deeper zoom appears to the lower right. Image credit: NASA/ESA/STScI/JHU

Take a close look at the pixelated red spot on the lower right portion of the image above, as it might be the oldest thing humanity has ever seen. This is a galaxy from the very early days of the Universe, and the light from the primordial galaxy traveled approximately 13.2 billion light-years before reaching the Spitzer and Hubble space telescopes. The telescopes — and the astronomers using them — had a little help from a gravitational lens effect to be able to see such a faint and distant object, which was shining way back when our Universe was just 500 million years old.

“This galaxy is the most distant object we have ever observed with high confidence,” said Wei Zheng, a principal research scientist in the department of physics and astronomy at Johns Hopkins University in Baltimore who is lead author of a new paper appearing in Nature. “Future work involving this galaxy, as well as others like it that we hope to find, will allow us to study the universe’s earliest objects and how the dark ages ended.”

This ancient and distant galaxy comes from an important time in the Universe’s history — one which astronomers know little about – the early part of the epoch of reionization, when the Universe began to move from the so-called cosmic dark ages. During this period, the Universe went from a dark, starless expanse to a recognizable cosmos full of galaxies. The discovery of the faint, small galaxy opens a window onto the deepest, most remote epochs of cosmic history.

“In essence, during the epoch of reionization, the lights came on in the universe,” said paper co-author Leonidas Moustakas, from JPL.

Because both the Hubble and Spitzer telescopes were used in this observation, this newfound galaxy, named MACS 1149-JD, was imaged in five different wavebands. As part of the Cluster Lensing And Supernova Survey with Hubble Program, the Hubble Space Telescope registered the newly described, far-flung galaxy in four visible and infrared wavelength bands. Spitzer measured it in a fifth, longer-wavelength infrared band, placing the discovery on firmer ground.

Objects at these extreme distances are mostly beyond the detection sensitivity of today’s largest telescopes. To catch sight of these early, distant galaxies, astronomers rely on gravitational lensing, where the gravity of foreground objects warps and magnifies the light from background objects. A massive galaxy cluster situated between our galaxy and MACS 1149-JD magnified the newfound galaxy’s light, brightening the remote object some 15 times and bringing it into view.

Astronomers use redshift to describe cosmic distances, and the ancient but newly-found galaxy has a redshift, of 9.6. The term redshift refers to how much an object’s light has shifted into longer wavelengths as a result of the expansion of the universe.

Based on the Hubble and Spitzer observations, astronomers think the distant galaxy was less than 200 million years old when it was viewed. It also is small and compact, containing only about 1 percent of the Milky Way’s mass. According to leading cosmological theories, the first galaxies indeed should have started out tiny. They then progressively merged, eventually accumulating into the sizable galaxies of the more modern universe.

The epoch of reionization refers to the period in the history of the Universe during which the predominantly neutral intergalactic medium was ionized by the emergence of the first luminous sources, and these first galaxies likely played the dominant role in lighting up the Universe. By studying reionization, astronomers can learn about the process of structure formation in the Universe, and find the evolutionary links between the smooth matter distribution at early times revealed by cosmic microwave background studies, and the highly structured Universe of galaxies and clusters of galaxies at redshifts of 6 and below.

This epoch began about 400,000 years after the Big Bang when neutral hydrogen gas formed from cooling particles. The first luminous stars and their host galaxies emerged a few hundred million years later. The energy released by these earliest galaxies is thought to have caused the neutral hydrogen strewn throughout the Universe to ionize, or lose an electron, a state that the gas has remained in since that time.

The paper is available here (pdf document).

Source: JPL

Did a Killer Asteroid Drive the Planet Into An Ice Age?

A simulation of the Eltanin strike

A simulation of the Eltanin meteor strike

When a mountain-sized asteroid struck the deep ocean off the coast of Antarctica 2.5 million years ago, it set off an apocalyptic chain of events: a devastating rain of molten rock and then a deadly tsunami that inundated the coastlines of the Pacific Ocean. But according to a team of Australian researchers, this was just the beginning. Then came a protracted ice age that killed off many of the Earth’s large mammals.

The Eltanin meteor, named after the USNS Eltanin which surveyed the area in 1964, is the only impact that has ever been discovered in a deep-ocean basin. These deep water impacts must be more common – so much of the planet is ocean – but they’re tricky to find because of the inaccessible depths of the impact craters. Researchers examining sediments in the area discovered tiny grains of impact melt and debris from meteorite fragments. Something big smashed this spot.

An asteroid strike on land is devastating, but an asteroid strike in the deep ocean is even worse. On both land and ocean, you get the plume of water vapor, sulfur, and dust blasted into the high atmosphere, raining molten rock down across a wide area. But for asteroid strikes in the ocean, this is followed by a devastating tsunami that inundates coastlines around the world. There are waves hundreds of meters high at the crash site, and they travel deep inland on every coastline. A local event becomes a global event.

But with the Eltanin meteor, this was followed by a prolonged ice age.

Professor James Goff and his colleagues from the University of New South Wales in Australia have been researching the Eltanin meteor and its after-effects. The timing of the impact seems to line up with geologic deposits in Chile, Australia and Antarctica. Geologists traditionally connected these deposits with slower geological processes, like glaciation. But Goff and his team think these deposits might have been dropped all at once by the devastating tsunami from Eltanin.

Here’s a video that shows how the impact and subsequent tsunami might have played out.

Although the Earth was already thought to be cooling in the mid to late Pliocene, the material kicked into the high atmosphere by Eltanin could have pushed the planet’s climate past the tipping point:

“There’s no doubt the world was already cooling through the mid and late Pliocene,” says co-author Professor Mike Archer. “What we’re suggesting is that the Eltanin impact may have rammed this slow-moving change forward in an instant – hurtling the world into the cycle of glaciations that characterized the next 2.5 million years and triggered our own evolution as a species.”

It was this time of a global ice age that transitioned the planet from the Pliocene to the Pleistocene. It was a bad time to be a Chalicothere or Anthracotheriidae, but a good time to be a hominid. So… thanks Eltanin.

View Larger Map

The location of the Elatin meteor crater

Original Source: Journal of Quaternary Science

SETI Astronomer Jill Tarter Recalls ‘Contact,’ 15 Years On

SETI's Jill Tarter. Credit: SETI


In 1985, famed astronomer, author and TV host Carl Sagan invited Jill Tarter to dinner at his house near Cornell University. Tarter, heavily involved with the Search for Extra-Terrestrial Intelligence, gladly accepted the chance to speak with Sagan, a member of SETI’s board of trustees.

Seated with Sagan and his wife, Ann Druyan, Tarter learned that Sagan had a fiction book on the go.

“Annie said, ‘You may recognize someone in the book, but I think you’ll like her,'” Tarter recalled in an interview with Universe Today.

Suspecting the character was based on herself, Tarter’s response to Druyan was: “‘Just make sure she doesn’t eat ice cones so much.’ It was something I was teased about.”

Female, in a male-dominated field

It was 15 years ago this month that the movie Contact, based on Sagan’s book of the same title, expanded to a run in international theatres after a successful summer in North America. The movie explores the implication of aliens making contact with Earth, but does it from more of a scientific perspective than most films.

While Contact, the movie did not talk about the pi sequences or advanced mathematical discussions in Contact, the book, it did bring concepts such as prime numbers, interference with radio telescopes, and the religion vs. science debate to theatres in 1997.

Tarter, who has just retired as the long-time director of the SETI Institute, said she was stunned by the parallels between her own life and that of Ellie Arroway, the character based on her in Contact. Both lost parents at an early age. Both also had to make their way in a field aggressively dominated by males.

Tarter recalls a meeting with fellow female scientists of her generation some years ago.

“A huge percentage of us had been, in high school, either cheerleaders or drum majorettes. This is so counterintuitive, right? Because we’re the nerds, we’re the brainy ones … (it was because) we were all competitors, and there weren’t any (female) sports to compete at. These sports were open, and we competed, and we generally won.”

Working on set

Tarter cautions the parallels did not totally match. The hopes and aspirations of Ellie in the book, and also the movie, were products of Sagan’s imagination. But the producers and actors of the film did want to get a close sense of what it was like to work with SETI.

After Jodie Foster was cast as Ellie, there were multiple phone calls between the actress and Tarter to discuss SETI.

“From her point of view, she was clear she wasn’t going to teach anyone astronomy. She was interested, in a personal way, about what the scientists were like,” Tarter said.

When the crew was filming at the Arecibo Observatory in Puerto Rico, Tarter flew there to observe the work, meet with Foster and also show the actress around. Tarter recalls bringing Foster up in a cabin that had a perfect view of the telescope, some 500 feet above the dish.

Microphones and walkie-talkies

Filming was an interesting process for Tarter, as well. There were the microphones, and the tools the crew used to check continuity. Most amusingly for Tarter, she observed Foster (reported height 5 feet, 2 inches) needing to stand on a box for most of the close-up shots with actor Matthew McConaughey (reported as 6 feet tall).

Two errors still irk Tarter today. There is a scene when Ellie gives a modified version of the Drake Equation, which calculates the odds of intelligent life who are capable of communicating with other life forms, and the calculations are all wrong. “It’s really infuriating,” Tarter said.

The other large mistake is a scene where Ellie gets a potential signal from space, while working at the Karl G. Jansky Very Large Array set of radio telescopes in New Mexico.

“She’s sitting in the middle of the array, in a car, with her laptop, and she gets the signal. And the first thing she does is pick up a walkie-talkie and start broadcasting. That signal is going to wipe out the signal from the sky. You don’t transmit by walkie-talkie.”

But overall, Tarter said the movie did a great job at portraying the feel of SETI. And Foster appreciated Tarter’s help. “She would write me handwritten thank-you notes, which was a kind of manner that most people have lost. A great courtesy.”

Hollywood outreach

Tarter walked the red carpet at the movie premiere and spent most of her time watching the film in tears of happiness. That euphoria evaporated when she saw the SETI Institute was not credited at the end of the film. When she talked to one of the film producers, she said she was informed that lawyers usually draft agreements specifying the length of time the credit appears, and the compensation received for doing so.

“We don’t have a lawyer at the SETI Institute,” she said. “When I write a paper, I acknowledge my collaborators. We got that wrong, so we never got any credit. We might have gotten even more recognition.”

But the professional connection with Foster still remains. Foster happily responded to a request from Tarter to do voice-overs for a video clip used for a SETI high school curriculum for integrated science. She also narrated a show, Life: A Cosmic Story, for the California Academy of Sciences Morrison Planetarium.

Tarter is now shifting into full-time outreach for SETI, saying the budgetary problems that shut down the organization’s Allen Telescope Array for several months last year were a warning call.

One of the organization’s newest initiatives is SETILive.org, which crowdsources analysis of signals from the Kepler Field. SETI solicits the public to take some time looking at the signal patterns, one at a time, in search of extraterrestrial communications.

“SETI is too important to allow it to fail,” Tarter said, adding her focus is finding substantial, stable funding from “that individual or institution that is capable of taking a long view.”

Adrenaline Rush: Standing on the Edge of a Spewing Volcano

This may be the most incredible volcano video ever filmed. Looking like it comes from the latest natural disaster flick, this incredible real footage was captured by Geoff Mackley, Bradley Ambrose, Nathan Berg, who came within 30 meters of the bubbling, spewing lava stream from the mouth the Marum volcano on Ambrym, a volcanic island in the archipelago of Vanuatu, off the east coast of Australia.

“Climbing down to within 30 metres of the lava it was so hot (1150 degrees) that without protection we could stand the heat for 6 seconds before retreating,” writes Mackley on his website. “With a respirator fire and heat resistant suit, [we] could stand on the edge and see the amazing spectacle for over 40 minutes.”

Wow! You can see some incredible images at Mackley’s website.
Continue reading “Adrenaline Rush: Standing on the Edge of a Spewing Volcano”

NASA’s Tribute to Sally Ride

Sally Ride

NASA officials, fellow astronauts and the family of Sally Ride gathered in Houston at the Johnson Space Center on Sept. 18, 2012. They remembered Ride’s life and the legend she leaves behind. An oak tree — one of most enduring types of trees — was planted and dedicated in Ride’s honor. It sits among 62 other trees dedicated to astronauts and space pioneers in a grove located JSC.

Ride passed away on July 23, 2012 after a courageous 17-month battle with pancreatic cancer. “She lived her life to the fullest, with boundless energy, curiosity, intelligence, passion, commitment, and love. Her integrity was absolute; her spirit was immeasurable; her approach to life was fearless,” wrote the team at Sally Ride Science — the science education company Ride founded — on the day of her death.

Award-Winning Short Film is Set on an Exoplanet

A new short film called “Grounded” portrays an astronaut stranded on another planet. The film combines great storytelling with stunning effects, and the visuals are nothing short of convincingly and stunningly real. But the ethereal, dream-like nature of the film is reminiscent of the ending of the movie “2001,” so, actually understanding the plot is not what the film is about. Instead it invites “unique interpretation and reflection by the viewer,” according to the description of the film. In under 8 minutes, the film explores themes of “aging, inheritance, paternal approval, cyclic trajectories, and behaviors passed on through generations,” which is ambitious for a sci-fi genre short. “Grounded” was written, directed, edited and produced by Kevin Margo. It is perhaps one of the best short films I’ve ever seen.
Continue reading “Award-Winning Short Film is Set on an Exoplanet”

Carnival of Space #267

This week’s Carnival of Space is hosted by Markus Hammonds at his Supernova Condensate blog.

Click here to read Carnival of Space #267.

And if you’re interested in looking back, here’s an archive to all the past Carnivals of Space. If you’ve got a space-related blog, you should really join the carnival. Just email an entry to [email protected], and the next host will link to it. It will help get awareness out there about your writing, help you meet others in the space community – and community is what blogging is all about. And if you really want to help out, sign up to be a host. Send an email to the above address.

Endeavour Poised for Final Takeoff on Sept. 19

Image caption: Endeavour atop the 747 SCA exits the Mate-Demate Device at the Kennedy Space Center Shuttle Landing Facility on Sept. 17. Credit: Ken Kremer

Everyone is hoping that the third time will be the charm to get the final flight of NASA’s three decade long shuttle program underway. See my gallery of shuttle Endeavour photos departing the gantry like Mate-Demate Device at the Shuttle Landing Facility (SLF).

Hordes of tourists from across the globe have descended on the Florida Space Coast to catch a glimpse of space history as Endeavour takes flight for the final time.

Space Shuttle Endeavour is poised for an early morning takeoff from the Kennedy Space Center (KSC) at first light on Wednesday, Sept. 19 following a two day delay due to poor weather conditions en route for the first leg of her cross country journey to California.

Image caption: Endeavour mated to NASA Boeing 747 at the Kennedy Space Center Shuttle Landing Facility on Sept. 17. Credit: Ken Kremer

In the meantime, local crowds of KSC workers and enthusiastic tourists are unexpectedly enjoying a few last bonus days of up close looks at NASA’s youngest shuttle orbiter atop a 747 Jumbo Jet known as the SCA or Shuttle Carrier Aircraft.

Endeavour awaits her departure orders firmly bolted on top of a specially modified 747 after being towed on Friday from the Vehicle Assembly Building (VAB) to the shuttle landing strip. The orbiter weighs nearly 200,000 pounds or 100 tons.

Liftoff of Endeavour from the SLF at KSC was originally planned for Monday, Sep 17 with a stop along the way at NASA’s Johnson Space Center (JSC) in Houston. But those carefully laid plans were derailed when a low pressure front materialized in the northern Gulf of Mexico generating a swatch of thunderstorms.

Image caption: Endeavour atop the SCA at Shuttle Landing Facility at KSC on Sept. 17. Credit: Ken Kremer

Managers could not find a safe path to Houston and twice scrubbed Endeavour’s takeoff.

With the weather delays, the cross country ferry flight has the feel of a space shuttle launch.

NASA plans to take the final takeoff decision down to the wire, following the last weather briefing at 5 a.m. on Wednesday.

Along the way from Kennedy to Johnson, the pair will conduct several low-level flyovers of NASA centers along the flight path at about 1500 feet at NASA’s Stennis Space Center in Mississippi and the Michoud Assembly Facility in New Orleans before landing at Ellington Field near JSC.

Image caption: Endeavour atop the 747 SCA exits the Mate-Demate Device at the Kennedy Space Center Shuttle Landing Facility on Sept. 17. Credit: Ken Kremer

At roughly 7:15 a.m. on Sept. 19, the SCA and Endeavour will depart Kennedy’s Shuttle Landing Facility and perform a flyover of various areas and beaches of the Space Coast, including Kennedy, the Kennedy Space Center Visitor Complex, Cape Canaveral Air Force Station and Patrick Air Force Base for 20 minutes for more.

Endeavour and the SCA will take a lengthy fly around victory lap around the Los Angeles area before landing at LAX at about 11.a.m PDT on Sept 21.

The orbiter will be towed along a 12 mile path through the streets of Inglewood and LA to the California Science Center. Eventually she will be displayed vertically, in launch configuration.

Endeavour flew 25 missions and traveled 122,883,151 miles during 299 days in space.

Ken Kremer

Image caption: Endeavour atop the SCA at Shuttle Landing Facility at KSC on Sept. 17. Credit: Ken Kremer

Using Gravity to Peer into the Most Violent Places in the Universe: Colliding Black Holes

Simulation of colliding black holes

Simulation of colliding black holes

Nothing matches the destructive power of a black hole; a singularity of dense matter with a gravitational pull so strong that nothing, not even light can escape. What goes in, doesn’t come back out. And so you can imagine how difficult it would be to probe the region inside a black hole’s event horizon. And yet, there’s a catastrophic event that should give scientists a momentary glance into the maelstrom, to partly understand what’s going on “in there.” That event would be the collision between two black holes.

As you probably know, there’s a supermassive black hole lurking at the heart of every galaxy. As these galaxies merge, these black holes encounter one another too. Sometimes a black hole is violently kicked into deep space, and other times they merge together into an even more super-supermassive black hole. The collision happens out of sight, beneath the shared event horizon. So, there’s no way to see what’s going on … and live to tell about it.

By looking at the gravity, however, astronomers might be able to peer right into the collision zone. One of the predictions made by Albert Einstein, as part of his famous General Theory of Relativity, is that dramatic gravitational events in the Universe, like the formation or collision of black holes should be detectable by the gravitational waves they generate. As these waves wash over us, the ripples in spacetime should be detectable by extremely sensitive instruments or spacecraft flying in formation.

A team of researchers from Cardiff University, Ioannis Kamaretsos, Mark Hannam and B. Sathyaprakash, have used a powerful supercomputer to simulate what kinds of gravitational waves might be generated by merging black holes. Two black holes orbiting one another should be emitting gravitational waves and gradually losing energy. This causes them to spiral inward, collide, and create a black hole which is highly deformed.

According to their simulation, the gravitational waves from this deformed black hole will give off a distinctive “tone”, like a ringing bell. In fact, by measuring only this tone, astronomers will be able to deduce both the mass of the black hole and the speed of its spin. Furthermore, the distortion of the gravitational waves should allow researchers to “see” what’s going on within the black hole’s event horizon; to understand what happened to the merging monsters after they disappeared beneath the shared event horizon.

“By comparing the strengths of the different tones, it is possible not only to learn about the final black hole, but also the properties of the original two black holes that took part in the collision,” Ioannis Kamaretsos said in a news release.

Of course, it’s important to note that gravitational waves themselves are still purely theoretical. Even though there are multiple ground-based detectors already built, and even more sensitive space-based detectors on the way, there hasn’t been a direct detection of a gravitational wave yet, only indirect detections. However, I wouldn’t bet against Einstein. He’s had a pretty good track record.

Original Source: Cardiff News Release

Timelapse: Space Shuttle Endeavour Mated to 747

Watch carefully, as this will be the last time ever this event will ever happen. At the Shuttle Landing Facility at NASA’s Kennedy Space Center in Florida, space shuttle Endeavour was mounted atop NASA’s Shuttle Carrier Aircraft, or SCA, in preparation for its ferry flight to California. The SCA, a modified 747 jetliner, will fly Endeavour to Los Angeles later this week, where it will be placed on public display at the California Science Center. This is the final ferry flight scheduled in the Space Shuttle Program era.