Kyle McMillan, GuestAccording to The Business Insider, Steve Jobs only downloaded one book, ever, to his iPad 2: Autobiography of a Yogi, by Paramahansa Yogananda. To those in the know, this should come as no surprise, as it was also his parting gift to all of the attendees at his funeral — the last gesture he made towards everyone closest to him on earth. Jobs’ spirituality was not widely well-known during his life, and while many will contest that certain busi [...]
This image shows a rare view of four quasars, indicated by white arrows, found together by astronomers using the Keck Observatory in Hawaii. The bright galactic nuclei are embedded in a giant nebula of cool, dense gas visible in the image as a blue haze. Hennawi & Arrigoni-Battaia, MPIA
The odds of success would make a Vegas bookie sit up and take notice. But in a one-in-10 million chance, astronomers surveying the sky have found a group of four tightly packed quasars in one of the most distant parts of the universe. The rare grouping may be a nascent galaxy cluster, and its unusually cold cradle of gas could prompt a re-think of how we model the early universe.
Quasars are among the brightest objects known—according to NASA, each one gives off more energy than 100 mature galaxies combined. But quasars are found only in the far reaches of the universe and can't be seen with the naked eye. Because of the time it takes light to travel that far, detecting such distant objects is akin to seeing back in time, so astronomers think quasars are the seeds of young galaxies, powered by gases falling into the supermassive black holes at their cores. As matter falls inward and gets close to the speed of light, it emits radiation that we can pick up with telescopes.
The quasar phase doesn't last long, only about a thousandth of a galaxy's lifetime. After that, the brightness dies down as the inflow of matter slows, says study leader Joseph Hennawi, an astrophysicist at the Max Planck Institute in Germany. Seeing any two quasars close together while they are still bright is a chancy business, so his team wasn't sure what they'd find when they set out to survey quasars using the W.M. Keck Observatory in Hawaii. To their surprise, they quickly pinpointed four of them in close proximity, cosmically speaking. The quartet is huddled up in an area of sky less than 600,000 light-years across that sits about 10 billion light-years from Earth.
"The authors found it by investigating the environment of just 29 bright quasars," says Michele Trenti, a senior lecturer at the University of Melbourne's School of Physics. "So at face value it seems like winning the lottery with a handful of tickets." That's not all that was strange about this quasar quartet. The foursome was found inside a cloud of cold, dark gas, and the team's observations suggest that similar clouds surround about 10 percent of the tens of thousands of known quasars. That's odd, because according to current theories, quasars in groups like this should be surrounded by hot plasma, or ionized gas, at a temperature of about 10 million degrees.
“What this means is that there is some physical process that the models aren’t capturing,” says Hennawi, whose team reports the discovery this week in Science.
May 3, 2015 / Greg Giles / Comments Off on 13 Things Anyone Who Loves A Highly Sensitive Person Should Know
Excerpt from huffingtonpost.com When I was in kindergarten, a boy in my class tossed my favorite book over our elementary school fence. I remember crying profusely, not because I was sad to see it go, but because I was so furious that he was s...
Excerpt from usatoday.comIts fuel tanks empty and its options gone, NASA's Messenger spacecraft smashed into planet Mercury on Thursday afternoon after valiantly fighting off the inevitable.Engineers calculated that the spacecraft, traveling a scorc...
Excerpt from space.com A telescope will soon allow astronomers to probe the atmosphere of Earthlike exoplanets for signs of life. To prepare, astronomer Lisa Kaltenegger and her team are modeling the atmospheric fingerprints for hundreds of potential alien worlds. Here's how: The James Webb Space Telescope, set to launch in 2018, will usher a new era in our search for life beyond Earth. With its 6.5-meter mirror, the long-awaited successor to Hubble will be large enough to detect potential biosignatures in the atmosphere of Earthlike planets orbiting nearby stars. And we may soon find a treasure-trove of such worlds. The forthcoming exoplanet hunter TESS (Transiting Exoplanet Survey Satellite), set to launch in 2017, will scout the entire sky for planetary systems close to ours. (The current Kepler mission focuses on more distant stars, between 600 and 3,000 light-years from Earth.)
Astronomer Lisa Kaltenegger
While TESS will allow for the brief detection of new planets, the larger James Webb will follow up on select candidates and provide clues about their atmospheric composition. But the work will be difficult and require a lot of telescope time. "We're expecting to find thousands of new planets with TESS, so we'll need to select our best targets for follow-up study with the Webb telescope," says Lisa Kaltenegger, an astronomer at Cornell University and co-investigator on the TESS team. To prepare, Kaltenegger and her team at Cornell's Institute for Pale Blue Dots are building a database of atmospheric fingerprints for hundreds of potential alien worlds. The models will then be used as "ID cards" to guide the study of exoplanet atmospheres with the Webb and other future large telescopes. Kaltenegger described her approach in a talk for the NASA Astrobiology Institute's Director Seminar Series last December. "For the first time in human history, we have the technology to find and characterize other worlds," she says. "And there's a lot to learn."
Detecting life from space
In its 1990 flyby of Earth, the Galileo spacecraft took a spectrum of sunlight filtered through our planet's atmosphere. In a 1993 paper in the journal Nature, astronomer Carl Sagan analyzed that data and found a large amount of oxygen together with methane — a telltale sign of life on Earth. These observations established a control experiment for the search of extraterrestrial life by modern spacecraft. "The spectrum of a planet is like a chemical fingerprint," Kaltenegger says. "This gives us the key to explore alien worlds light years away." Current telescopes have picked up the spectra of giant, Jupiter-like exoplanets. But the telescopes are not large enough to do so for smaller, Earth-like worlds. The James Webb telescope will be our first shot at studying the atmospheres of these potentially habitable worlds. Some forthcoming ground-based telescopes — including the Giant Magellan Telescope (GMT), planned for completion in 2020, and the European Extremely Large Telescope (E-ELT), scheduled for first light in 2024 — may also be able to contribute to that task. [The Largest Telescopes on Earth: How They Compare] And with the expected discovery by TESS of thousands of nearby exoplanets, the James Webb and other large telescopes will have plenty of potential targets to study. Another forthcoming planet hunter, the Planetary Transits and Oscillations of stars (PLATO), a planned European Space Agency mission scheduled for launch around 2022-2024, will contribute even more candidates. However, observation time for follow-up studies will be costly and limited. "It will take hundreds of hours of observation to see atmospheric signatures with the Webb telescope," Kaltenegger says. "So we'll have to pick our targets carefully."
Set to see its first light in 2021, The Giant Magellan Telescope will be the world’s largest telescope.
Getting a head start
To guide that process, Kaltenegger and her team are putting together a database of atmospheric fingerprints of potential alien worlds. "The models are tools that can teach us how to observe and help us prioritize targets," she says. To start, they have modeled the chemical fingerprint of Earth over geological time. Our planet's atmosphere has evolved over time, with different life forms producing and consuming various gases. These models may give astronomers some insight into a planet's evolutionary stage. Other models take into consideration the effects of a host of factors on the chemical signatures — including water, clouds, atmospheric thickness, geological cycles, brightness of the parent star, and even the presence of different extremophiles. "It's important to do this wide range of modeling right now," Kaltenegger said, "so we're not too startled if we detect something unexpected. A wide parameter space can allow us to figure out if we might have a combination of these environments." She added: "It can also help us refine our modeling as fast as possible, and decide if more measurements are needed while the telescope is still in space. It's basically a stepping-stone, so we don't have to wait until we get our first measurements to understand what we are seeing. Still, we'll likely find things we never thought about in the first place."
A new research center
The spectral database is one of the main projects undertaken at the Institute for Pale Blue Dots, a new interdisciplinary research center founded in 2014 by Kaltenegger. The official inauguration will be held on May 9, 2015. "The crux of the institute is the characterization of rocky, Earth-like planets in the habitable zone of nearby stars," Kaltenergger said. "It's a very interdisciplinary effort with people from astronomy, geology, atmospheric modeling, and hopefully biology." She added: "One of the goal is to better understand what makes a planet a life-friendly habitat, and how we can detect that from light years away. We're on the verge of discovering other pale blue dots. And with Sagan's legacy, Cornell University is a really great home for an institute like that."View Article Here Read More
It sounds almost like a late ’90s sci-fi flick: NASA sends a spacecraft to an asteroid, plucks a boulder off its surface with a robotic claw, and brings it back in orbit around the moon. Then, brave astronaut heroes go and study the space rock up close—and bring samples back to Earth. Except it’s not a movie: That’s the real-life idea for the Asteroid Redirect Mission, which NASA announced today. Other than simply being an awesome space version of the claw arcade game (you know you really wanted that stuffed Pikachu), the mission will let NASA test technology and practice techniques needed for going to Mars. The mission, which will cost up to $1.25 billion, is slated to launch in December 2020. It will take about two years to reach the asteroid (the most likely candidate is a quarter-mile-wide rock called 2008 EV5). The spacecraft will spend up to 400 days there, looking for a good boulder. After picking one—maybe around 13 feet in diameter—it will bring the rock over to the moon. In 2025, astronauts will fly NASA’s still-to-be-built Orion to dock with the asteroid-carrying spacecraft and study the rock up close. Although the mission would certainly give scientists an up-close opportunity to look at an asteroid, its main purpose is as a testing ground for a Mars mission. The spacecraft will test a solar electronic propulsion system, which uses the power from solar panels to pump out charged particles to provide thrust. It’s slower than conventional rockets, but a lot more efficient. You can’t lug a lot of rocket fuel to Mars. Overall, the mission gives NASA a chance at practicing precise navigation and maneuvering techniques that they’ll need to master for a Mars mission. Such a trip will also require a lot more cargo, so grabbing and maneuvering a big space rock is good practice. Entering lunar orbit and docking with another spacecraft would also be helpful, as the orbit might be a place for a deep-space habitat, a rendezvous point for astronauts to pick up cargo or stop on their way to Mars. And—you knew this part was coming, Armageddon fans—the mission might teach NASA something about preventing an asteroid from striking Earth. After grabbing the boulder, the spacecraft will orbit the asteroid. With the added heft from the rock, the spacecraft’s extra gravity would nudge the asteroid, creating a slight change in trajectory that NASA could measure from Earth. “We’re not talking about a large deflection here,” says Robert Lightfoot, an associate administrator at NASA. But the idea is that a similar technique could push a threatening asteroid off a collision course with Earth. NASA chose this mission concept over one that would’ve bagged an entire asteroid. In that plan, the spacecraft would’ve captured the space rock by enclosing it in a giant, flexible container. The claw concept won out because its rendezvous and soft-landing on the asteroid will allow NASA to test and practice more capabilities in preparation for a Mars mission, Lightfoot says. The claw would’ve also given more chances at grabbing a space rock, whereas it was all or nothing with the bag idea. “It’s a one-shot deal,” he says. “It is what it is when we get there.” But the claw concept offers some choices. “I’ve got three to five opportunities to pull one of the boulders off,” he says. Not bad odds. Better than winning that PikachuView Article Here Read More