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False-color view of cloud features on Venus taken by Europe’s now-defunct Venus Express spacecraft. Credit: ESA/MPS/DLR/IDA

Scientists interested in studying Venus, as well as other extreme places in the solar system, now have an option besides expensive, one-off space missions. A new test rig at NASA’s Glenn Research Center in Ohio can replicate the planet’s lead-melting temperature, crushing pressure and noxious mix of atmospheric gases to create a similar hell on Earth.

“You don’t have to go Venus now to do Venus atmospheric research,” Daniel Vento, project manager for the Glenn Extreme Environment Rig, or GEER, told Discovery News.

NEWS: Venus May Have Once Been Awash With CO2 Oceans

Inside the 14-ton, stainless steel, 3- by 6-foot chamber, temperatures can soar beyond 900 degrees Fahrenheit, hotter than the surface of Venus. At the same time, pressure can reach nearly 100 times the weight of Earth’s atmosphere at sea level. 

Add carbon dioxide, which comprises 96 percent of Venus’ atmosphere, nitrogen and a sprinkling of other chemicals and scientists can replicate the superfluid physics that shape another world. [10 Weirdest Facts About Venus]

Other test chambers have been able to replicate components of a planet’s atmosphere, but GEER takes the simulation a step beyond. “We wanted to do everything at once,” Vento said.

ANALYSIS: Baked Exoplanet Gets Lab Treatment

Engineers plan to outfit GEER with infrared spectrometers and other instruments so scientists can, for example, watch minerals interact and evolve in a Venus-like setting. The chamber also can be set up to replicate Jupiter and Saturn, both warm environments.

With the addition of cooling walls, GEER one day could be used to simulate Uranus and other frozen worlds of the outer solar system. “The long-term plan for GEER is to be able to run any planetary atmosphere,” Vento said.

Glenn Research Center, known mainly for its work in aeronautics and rocket engines, didn’t intend to get into the planetary science business. But more than a decade ago, engineers were working on a methane rocket engine and ended up with a test facility that also replicated conditions on Titan, Saturn’s largest moon.

Explainer: Venus Volcanoes May Be Alive After All

GEER’s roots stem from another technology initiative to develop a cryocooler. When the program was canceled, the equipment was converted into the extreme environment rig.

“Turns out, the atmosphere of Venus has an awful lot in common with the inside of a jet engine,” Vento said.

In addition to scientific research, GEER also will be used to test sensors and equipment, such as high-temperature electronics, that one day could enable long-duration surface missions to Earth’s mysterious sister planet.

This article was provided by Discovery News.

An artist’s impression of Alpha Centauri, which involves two close-orbiting stars, with an Earth-mass planet in orbit around one. A third star orbits the close pair from a distance. Credit: ESO/L. Calçada/Nick Risinger (skysurvey.org)

Astronomers have long struggled with how young planets form around pairs of stars without destroying themselves, but new research suggests it can be done with the perfect setup: a massive, slightly elongated disk of debris from the star.

Planets forming around a star with another stellar neighbor nearby must somehow overcome the gravity of the second star during the formation process. A new view of the process suggests that the material in two-sun systems similar to Tatooine in “Star Wars” can indeed overcome the star’s destructive pull and form planets, even very small ones — if the planet-forming material around the star is sufficiently massive and the disk of material is slightly stretched.

“It may seem surprising given the disk is less massive, but if you’re moving far from the central star a lot of the disk material is around you, while the central binary is concentrated toward the center,” Kedron Silsbee, a graduate student at Princeton University, said at the recent Emerging Researchers in Exoplanet Science Symposium at Pennsylvania State University. Working with Roman Rafikov, also of Princeton, Silsbee modeled planetary formation in close binaries. “It turns out the disk can actually be the dominant component,” Silsbee said. [How 2 ‘Tatooine’ Planets Orbit Twin Stars (Infographic)]

The dust is mightier than the star

Planets form from the disk of dust and gas left over after their parent star is born. When that star is one of a pair, its companion can have a disruptive effect on planet formation. Previous studies have shown that binary stars separated by less than 20 times the Earth-sun distance should feel too much gravitational disruption from the companion star to form a planet around the host star.

With half the stars in the solar system part of a binary system, this appears to be bad news for planet formation. Yet more than 20 percent of planets found using the same method as NASA’s Kepler spacecraft exist around binary stars. To date, five planetary systems are known to exist around stars in  close binaries: Three of them house massive Jupiter-size planets, while the other two have smaller satellites, including Alpha Centauri, which has an Earth-mass planet.  Since their discovery, scientists have puzzled over how they could have formed.

Planetary embryos form as gravity draws bits of gas and dust together. But if two pieces of rock are traveling too fast compared to one another, they will not merge but will instead suffer a catastrophic collision that may shatter one or both pieces at worst, and knock smaller pieces off at best. At the same time, the gravitational tug of the companion star will stretch the orbit of the dust and rock in the disk, causing them to collide at different speeds and angles that are not ideal for planetary formation.

Think of it as a series of (very small) cars racing around the track of the disk. If two cars are traveling in roughly the same direction at comparable speeds, a small brush between the two of them causes very little damage (in this scenario, they would merge into a single car). However, if they are traveling at wildly different speeds, they will ricochet off one another, often with fatal results. A companion star would pull on that disk, sending the “cars” careening around in an unorderly fashion and smashing into one another more destructively.

Silsbee and Rafikov modeled the formation of planet embryos, or planetesimals, in close binaries while for the first time factoring in the disk’s own gravitational pull to help slow down the ricocheting action. The pair realized that if the disk was mildly eccentric — not perfectly circular but not significantly stretched out, either — the dust and rock would travel in orbits that would allow for smoother merging.

The researchers found that a massive enough disk — at least a hundredth of the mass of the sun — could overwhelm the gravitational pull of the disruptive companion star, maintaining the slightly stretched elliptical orbit that allowed pieces to mesh together and smoothly form planets.

“You basically want a massive disk in order for the disk gravity to dominate over the binary companion,” Silsbee said.

Although observations of close binaries have not yet revealed sufficiently massive disks, Rafikov and Silsbee said that the presence of Jupiter-mass planets in the observed systems suggests that the stars once housed disks large enough to form the enormous planets present today.

“Disk mass cannot be much lower than at least several Jupiter masses, otherwise the disk simply would not contain enough gas to form these massive objects,” the pair said in one research paper.

The research was a detailed in May in a series of three papers in the Astrophysical Journal.

Follow us @Spacedotcom, Facebook and Google+. Original article on Space.com.

California-based company Arx Pax has developed a hoverboard using “Magnetic Field Architecture” technology. Credit: Arx Pax

It’s a vision of the future that may even have eluded Marty McFly: hoverboard tech in space.

NASA wants to make this vision a reality, and soon. The space agency is teaming up with California-based company Arx Pax, which has developed a real-life hoverboard using a technology called Magnetic Field Architecture (MFA).

The collaboration — which takes the form of a Space Act Agreement — aims to find a way to manipulate tiny satellites called cubesats without actually touching them.

“Arx Pax and NASA will work together to design a device with the ability to attract one object to another from a distance,” Arx Pax representatives said in a statement today (Sept. 2). “The device will draw, as well as repel, satellites at the same time, meaning it will hold a satellite at a distance and won’t allow it to move away or toward the capture device. This will enable the capability to capture, and possibly manipulate, microsatellites or other objects without making physical contact with them.” [Science Fiction or Fact? 10 Out-There Concepts]

Arx Pax has built MFA tech into engines that create and manipulate magnetic fields, allowing them to hover over conductive surfaces. One such “hover engine” drives Arx Pax’s Hendo Hoverboard, which was introduced in October 2014.

The same principle can theoretically be applied to move and control cubesats, which can be smaller than a cereal box. (The basic building blocks of cubesats are “units” that measure 4 inches, or 10 centimeters, on a side. “3U” cubesats are the size of three of these units put together, 6U cubesats are as big as six of them, and so on.)

But a space-based hover engine wouldn’t draw spacecraft in from far away like a tractor beam from “Star Trek.”

“We’re talking on the scale of centimeters,” Arx Pax co-founder and CEO Greg Henderson told The Verge.

The company and NASA plan to develop a prototype of the cubesat-moving device over the next couple of years, The Verge reported.

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

Credit: NASA/GSFC

Credit: ROSCOSMOS/NASA/mash mix: Space.com

A new view of the Prawn Nebula shows “cosmic recycling” at work: Glowing clusters of newborn stars illuminate surrounding gas, expelled from an earlier stellar generation, which will eventually form into even newer stars.

The 2.2-meter telescope at the European Southern Obsevatory’s La Silla Observatory in Chile snapped a choice section of the reddish nebula studded by young blue stars in a newly released image. The nebula, also called Gum 56 and IC 4628, is hard to see with the naked eye although it’s around 250 light-years across — it is very faint, and mostly emits light at wavelengths not visible to humans.

That invisibility conceals a lot of action, as new stars form from the stellar nursery of the nebula’s gas and debris: “The material forming these new stars includes the remains of the most massive stars from an older generation that have already ended their lives and ejected their material in violent supernova explosions,” ESO officials said in a statement. “Thus the cycle of stellar life and death continues.” When the dust and gas grows dense enough, a portion will collapse down into the beginnings of a star. [Video: See How Cosmic Recycling Seeds the Prawn Nebula]

Large clouds of charged hydrogen gas provide the red glow to the nebula. As ultraviolet energy is emitted from the young stars, it hits the nearby hydrogen and excites it, prompting the release of light with hydrogen’s distinct reddish tinge.

This new image, taken from the La Silla Observatory in Chile, spotlights part of the Prawn Nebula where newborn stars stud clouds of gas and dust.
Credit: ESO

The source of most of that radiation is a pair of rare, extremely bright blue giant stars (out of view in this photo). The huge, powerful stars have short life spans — only a million years or so before exploding into a supernova — and they generally appear in areas with rapid star growth.

Despite the rare stars, the area has not been carefully explored (besides in an extremely detailed 2013 image): “Given the two very unusual blue giants in this area and the prominence of the nebula at infrared and radio wavelengths, it is perhaps surprising that this region has been comparatively little studied as yet by professional astronomers,” ESO officials said in the statement.

Email Sarah Lewin at slewin@space.com or follow her @SarahExplains. Follow us @Spacedotcom, Facebook and Google+. Original article on Space.com

This artist’s concept shows Kepler-62f, an exoplanet in the habitable zone of its host star, which is located about 1,200 light-years from Earth in the constellation Lyra. Researchers think Kepler-62f may be a “water world.” Credit: NASA/Ames/JPL-Caltech

The bright glint of alien oceans may be visible from afar, allowing astronomers to flag potentially habitable exoplanets.

As Earth travels around the sun, it moves through phases much like the moon when seen from afar. The planet’s oceans reflect a great deal of light, especially during the crescent phase. The same principle should apply to exoplanets, researchers say.

“Seeing excessive brightness at the crescent phases could be a telltale signal of ocean planets,” Tyler Robinson, of NASA’s Ames Research Center in Moffett Field, California, said at the Astrobiology Science Conference in Chicago in June. [‪10 Exoplanets That Could Host Alien Life]

Although a host of satellites monitor Earth, few eye the planet as a whole. As a result, many exoplanet scientists turn to models to understand how Earth might appear if it were a distant alien world. However, the accuracy of these models can be difficult to gauge without observations to verify them.

Scientists have made a few attempts to address this issue. In 1993, for example, Carl Sagan and other researchers used observations made by NASA’s Jupiter-studying Galileo spacecraft during a 1990 flyby of Earth to search for signs of life on our planet.

An image of Earth, taken by NASA’s LCROSS satellite, shows the planet in its crescent phase. The smaller light to the left is the moon.
Credit: NASA

And in 2009, NASA’s Lunar Crater Observation and Sensing Satellite(LCROSS) moon mission observed Earth at several phases, including near-full and crescent, in order to calibrate its instruments. Robinson and his colleagues analyzed these data, and found that the near-infrared and ultraviolet/visible light observations provided an approximation of how Earth might appear through extreme phases across various spectrums. Their study was published in 2014 in The Astrophysical Journal.

“LCROSS looked at Earth for calibration, but its measurements were good for science,” Robinson said.

The results showed that, although less of Earth’s surface was visible during its crescent phase, the brightness of the planet increased due to the light reflecting off its oceans. In visible light, the glint increased the planet’s brightness by as much as 40 percent; in the near-infrared, Earth shone nearly 80 percent more brightly, Robinson said.

Robinson was also a co-author on a different paper that examined similar, though less detailed, observations of Earth using NASA’s Deep Impact spacecraft (which performed up-close examinations of two different comets, in 2005 and 2010).

The observations performed by LCROSS — the first high-spectral-resolution observations of Earth in its crescent phases — lined up well with predictions based on existing models, Robinson said.

Alien Planet Quiz: Are You an Exoplanet Expert?

Astronomers have confirmed more than 800 planets beyond our own solar system, and the discoveries keep rolling in. How much do you know about these exotic worlds?

0 of 10 questions complete

Alien Planet Quiz: Are You an Exoplanet Expert?

Astronomers have confirmed more than 800 planets beyond our own solar system, and the discoveries keep rolling in. How much do you know about these exotic worlds?

0 of questions complete

However, similar results gained from observations of an exoplanet would not automatically be signs of an ocean, he cautioned; clouds and ice could also affect the brightness of a planet. Follow-up studies of the exoplanet’s atmospherecould reveal more about the world’s potential habitability.

Still, an apparent glint from an exoplanet ocean would be an exciting find, Robinson said.

“We conclude that the detection of such a feature would be intriguing, and would certainly indicate that a more detailed observational follow-up of the planet was warranted,” he and his colleagues wrote in their 2014 LCROSS paper.

Follow Nola Taylor Redd on Twitter @NolaTRedd Follow us @Spacedotcom, Facebook or Google+. Originally published on Space.com.

Credit: ESO/Nick Risinger (skysurvey.org)

An unmanned Atlas V rocket carrying the U.S. Navy’s Mobile User Objective System 4 satellite (MUOS-4) launches into space from Florida’s Cape Canaveral Air Force Station in a pre-dawn liftoff on Sept. 2, 2015. Credit: United Launch Alliance

The United States Navy launched an advanced new tactical communications satellite into orbit today (Sept. 2) to join a growing network designed to aid U.S. military forces stationed around the world. 

An unmanned Atlas V rocket carrying the Navy’s fourth Mobile User Objective System satellite, or MUOS-4, lit up the pre-dawn sky in a dazzling display as it lifted off from a launchpad at Florida’s Cape Canaveral Air Force Station at 6:18 a.m. EDT (1018 GMT). It will eventually assume a geosynchronous orbit above Earth. The mission, which was overseen by the U.S. launch provider United Launch Alliance (ULA) was originally scheduled for Aug. 31, but delayed due to bad weather.

The satellite is the fourth installment in the MUOS communications system, which is “designed to significantly improve ground communications for U.S. forces on the move,” according to a statement from Lockheed Martin, is building a total of five MUOS satellites for the U.S. military.

The first two MUOS satellites launched in 2012 and 2013. The third MUOS satellite launched in January and is still undergoing testing before it becomes fully operational.

A camera mounted to a United Launch Alliance Atlas V rocket captures an amazing view of the Earth from space while launching the U.S. Navy’s Mobile User Objective System 4 satellite (MUOS-4) on Sept. 2, 2015.
Credit: United Launch Alliance

A United Launch Alliance Atlas V rocket carrying the MUOS-4 satellite mission for the U.S. Navy lifted off from Space Launch Complex 41 at the Cape Canaveral Air Force Station at 6:18 a.m. ET.
Credit: United Launch Alliance

Lockheed Martin, the company that built the MUOS satellites, created this graphic to show how the MUOS communications array benefits the U.S. military.
Credit: Lockheed Martin

“The MUOS works like a smartphone network in space, vastly improving secure satellite communications for mobile U.S. forces,” Navy Commander Paul Benishek said in a ULA webcast just after liftoff.

MUOS is particularly helpful for troops in remote locations, because these soldiers can transmit and receive high-quality communications when the satellites are beyond the line of sight. All U.S. military services will be able to use the MUOS system, the statement said.

“MUOS provides satellite communications in the narrowband spectrum,” Navy officials said in a statement. “Although narrowband communication is less than 2 percent of total Department of Defense [DoD] bandwidth, it represents more than 50 percent of all DoD satellite communication users. In addition to ad-hoc situations such as disaster response, narrowband represents the majority of communications for SEAL teams.”

This is the 56th launch of an Atlas V rocket by ULA since the rocket’s debut in 2002. It is the sixth launch of an Atlas V rocket in the 551 configuration, which refers to the size of the payload capsule (5.4 meters or 17.7 feet wide), the number of solid rocket boosters (five) and the number of engines (one).

The next MUOS satellite, MUOS-5, is expected to launch in 2016.

Follow Calla Cofield @callacofield.Follow us @Spacedotcom, Facebook and Google+. Original article on Space.com.