Science Movies to Avoid on Date Night - Discovery News

Another criminally underappreciated sci-fi film, director Andrew Niccol's 1997 "Gattaca" deals with both the hard science and social science aspects of human genetics technology. In a near-future setting, a kind of popular eugenics system allows parents to genetically profile embryos prior to implantation, selecting for optimal hereditary traits. Uma Thurman and Ethan Hawke -- surely two of our most genetically gifted movie stars -- must navigate a scary future society in which destiny is determined by genes. The name of the space agency in the film, Gattaca, is composed of the letters GATC -- or guanine, adenine, thymine and cytosine, the four bases of DNA.

While there's nothing particularly gross or disturbing in "Gattaca," the very subject matter -- and the presence of those two elite specimens Thurman and Hawke -- might lead a romantic interest to start questioning your own genetic potential.

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Quasars Still Mystify Scientists 50 Years After Discovery

Half a century after first getting a bead on quasars, astronomers still lack a basic understanding of how the most luminous objects in the universe work, a prominent researcher says. 

Scientists first measured the distance to a quasar — an incredibly bright galactic core powered by a supermassive black hole — 50 years ago this Saturday (March 16), finding that it lay billions of light-years away.

The discovery was a seminal one in astronomy, opening the distant, ancient universe to observation and study. But in the decades since, researchers have shed little light on the powerful engine that drives quasars, says astrophysicist Robert Antonucci of the University of California, Santa Barbara.

"We have found thousands of quasars in the past 50 years, but we still don't have good physical models for how they radiate their prodigious energy," Antonucci writes in the current issue of the journal Nature, which was published online today (March 13). "Without predictive the­ories, we have nothing. Our best hope for understanding quasars is that extraterrestrials might drop in and explain them to us." [Most Powerful Quasar Discovered (Video)]

The brightest objects in the universe

Quasars radiate energy broadly across the electromagnetic spectrum, but they take their name from their radio emissions. Astronomers dubbed them"quasi-stellar radio sources" because the signals appeared to be coming from one place, like a star. The shortened version of the moniker, "quasar," stuck.

Many quasars blast out twin jets of particles that travel at nearly the speed of light, which in turn create enormous, radio-emitting "lobes" near the quasars, Antonucci writes.

Scientists think quasars and other types of active galactic nuclei mark a particular stage in the lifetime of galaxies, one at which their central black holes, which can be more massive than 10 billion suns, are gobbling up lots of gas, dust and other matter.

"This trait was more com­mon in the past, so there are fewer quasars today," Antonucci writes. "Now starved of fuel, black holes linger in galaxies, including our Milky Way."

Questions remain

Astronomers have been documenting ever-more distant quasars, pushing back closer and closer to the Big Bang that created our universe 13.7 billion years ago. But a fundamental understanding of quasars remains elusive, Antonucci says.

"The theory of radio sources has not changed significantly in the past 30 years," he writes. "Basic questions remain: do the jets and lobes comprise electrons and protons or electron-positron pairs? Do the protons carry a lot of energy, as cosmic rays do? Is the energy divided evenly between electric and magnetic fields? Without answers to these [questions], we can set only lower limits on how much energy the jets and lobes hold."

It doesn't help that astrophysicists continue to investigate quasars using models developed for much smaller black holes, Antonuccci says.

"These models simply don't match the observations without lots of special pleading," he writes. "The properties of small accretion disks that are inferred to exist around stel­lar-mass black holes cannot be scaled up to explain the spectra of much more luminous quasars."

But a better understanding of quasars is achievable, Antonucci adds, urging his colleagues to work on developing advanced computational models of black-hole systems. And more sensitive X-ray telescopes could make a difference, too.

"The important thing is that the X-rays come from so extremely close to the black hole, much closer than the optical light," Antonucci told SPACE.com via email. "So it offers a hope of giving us a picture of the 'central engine' of the black hole, where the gravitational potential energy is actually produced. That's where the money is."

Antonucci voiced optimism that astronomers will unlock quasars' key mysteries, though he's not sure about the timeline.

"Eventually, I suppose we'll get it, although I may be in heaven by then, or else in the other place!" he told SPACE.com.

Follow Mike Wall @michaeldwall. Follow us @Spacedotcom, Facebook or Google+. Originally published on SPACE.com.

Copyright 2013 SPACE.com, a TechMediaNetwork company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

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Mars Discovery Highlights Need for Sample-Return Mission, Scientist Says

The announcement this week that Mars definitely could have supported some form of life in the ancient past is an unmistakable reminder that future missions to the Red Planet should focus on bringing Martian rock samples back to Earth, a celebrated planetary scientist says.

NASA unveiled the discovery on Tuesday (March 12) with a bold announcement that Mars could have supported primitive life at some point billions of years ago. The Martian find was made with the help of NASA's Mars rover Curiosity, the largest rover ever to explore the Red Planet. But in order to create a clear picture of the story of habitability and life on Mars, scientists will need to get their hands on fresh samples of the planet collected by an ambitious future mission.

"On the one hand, it shows what we can do with instruments on the surface of Mars," Bruce Betts, the director of projects at the Planetary Society, told SPACE.com. "We'll always be able to do more with our labs on Earth than what we can do on Mars."

The Curiosity rover was able to bore into a Martian rock and find evidence of a habitable environment, but more comprehensive work can be done in labs on Earth, Betts said.

For this reason, scientists like Betts have campaigned to have sample return added as non-negotiable for the next mission to the Red Planet.

NASA is taking the concept seriously. Sample return is at the top of the space agency's list when planning for missions to Mars in the next decade, Betts added. NASA has placed it as the highest priority for any new missions to the Red Planet. [The Search for Life on Mars (A Photo Timeline)]

"You want rocks that are carefully collected," Betts said.

It's important to know exactly where the rocks are coming from, Betts said. If scientists know the context in which the rocks were found, it will help them analyze them in a broader context. 

Although there are no solid plans to build sample return into a mission currently in development, future NASA missions are using other means to investigate the Martian interior and exterior.

The MAVEN mission — a Mars orbiter launching later this year — will investigate the ionosphere of the Red Planet to see how carbon dioxide, oxygen and other compounds could have dissipated over time, leaving Mars with the cold, arid atmosphere scientists see today. 

NASA's InSight Mars is a lander that will burrow deep into the Martian dirt to learn more about the planet's geological evolution. It is on track to launch in 2016. The agency is also planning to launch a new Mars rover in 2020, but it won't have the capability for sample return. 

Europe and Russia are also planning new Mars missions together, including an orbiter and the ExoMars rover.

NASA's announcement on Tuesday means that astronomers are one step closer to understanding what a primitive Mars could have looked like, something that missions in the future will help clarify, Betts added.

"I think the findings like today's continue to increase the interest in Mars as a complex and interesting place," Betts said.

Follow Miriam Kramer @mirikramer and Google+. Follow us @Spacedotcom, Facebook and Google+. Original article on SPACE.com.

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