NASA Says 2 Asteroids Will Safely Fly By Earth This WeekendScientists Discover Possible Interstellar Visitor Stay on target It’s long been a feature of speculative fiction, but terraforming Mars — like for real — is probably going to be harder than we’d probably hoped. At least according to new research by NASA, which suggests even the most aggressive route — literally nuking Mars to habitability — won’t be enough to make water wet on the surface of the red planet.The basic concept is sound — pump the air full of gasses that can trap heat. Use that to make it nice and toasty, and hopefully those gasses turn out to be breathable ones. I mean, we’re already kinda mucking this up here on Earth and Venus is well past screwed, with a surface hot enough to melt many metals outright. So, what’s the trouble with Mars?Well, it turns out there just isn’t enough atmosphere — even with the human-powered boost. Earth and Venus, for instance, both have complex atmospheres with loads of different chemicals. Each of them can block a specific band of radiation, and while CO2 can pull off some pretty wicked things here, where there’s a complex cocktail of chemistry working together to heat up the planet (which is why many people refer to greenhouse gasses in general and not just CO2 these days). “Carbon dioxide and water vapor are the only greenhouse gases that are likely to be present on Mars in sufficient abundance to provide any significant greenhouse warming,” said Bruce Jakosky of the University of Colorado in a release. “In addition, most of the CO2 gas is not accessible and could not be readily mobilized. As a result, terraforming Mars is not possible using present-day technology.”Even if all the carbon on Mars were tapped, the air pressure alone would be a small fraction of what is needed. To say nothing of it being breathable, or usable, or comfortable. There is evidence to suggest that Mars may once have been a haven for life. And, with liquid water now discovered, it’s possible the planet still harbors something. But it’s critical resources — like air — have long since been lost to the void. Maybe one day we can make the place a second home, but we have a long-ass way to go.Stay up to date on all the latest ongoings of our favorite red planet here. Let us know what you like about Geek by taking our survey.
Stay on target It’s official! The Voyager 2 probe has entered interstellar space, making it just the second human-made object to do so.NASA announced on Monday that the Voyager 2 probe has exited the heliosphere — the protective bubble of particles and magnetic fields created by the Sun.After comparing data from different instruments aboard the spacecraft, mission scientists determined the probe crossed the outer edge of the heliosphere on November 5, according to NASA. This boundary, called the heliopause, is where the tenuous, hot solar wind meets the cold, dense interstellar medium.The probe is now more than 11 billion miles from Earth.“I think we’re all happy and relieved that the Voyager probes have both operated long enough to make it past this milestone,” Voyager Project Manager Suzanne Dodd said in a statement. “This is what we’ve all been waiting for. Now we’re looking forward to what we’ll be able to learn from having both probes outside the heliopause.”The Voyager 2 is no stranger to milestones. Launched in 1977, it is the only spacecraft to study all four of the solar system’s giant planets at close range, and is NASA’s longest-running mission.It explored the Jupiter, its magnetosphere, and moons in greater detail than had the Pioneer spacecraft that preceded it. Voyager 2 also used Jupiter as a springboard to Saturn, using the gravity-assist technique. It was able to observe Saturn’s rings at much higher resolution and to discover many more ringlets.Voyager 2 also became the first spacecraft to visit Uranus, where it discovered 10 new moons, two new rings, and a strangely tilted magnetic field stronger than that of Saturn.And the spacecraft is still the only human-made object to have flown by Neptune. In the closest approach of its entire tour, Voyager 2 passed less than 5,000 km above the planet’s cloud tops. It discovered five moons, four rings, and a “Great Dark Spot” that vanished by the time the Hubble Space Telescope imaged Neptune five years later.Illustration shows the position of NASA’s Voyager 1 and Voyager 2 probes, outside of the heliosphere, a protective bubble created by the Sun that extends well past the orbit of Pluto. (Photo Credit: NASA/JPL-Caltech)Though it launched a couple weeks before its twin Voyager 1, its trajectory took it on a longer route through the solar system. Voyager 1 reached interstellar space in 2012. Voyager 2 also carries a working instrument that will provide first-of-its-kind observations of the nature of this gateway into interstellar space.Mission operators still can communicate with Voyager 2 as it enters the new phase of its journey, but information – moving at the speed of light – takes about 16.5 hours to travel from the spacecraft to Earth. By comparison, light traveling from the Sun takes about eight minutes to reach Earth.More on Geek.com:NASA Advises Avengers on Saving Tony StarkNASA Recorded the Sound of Mars (And It’s Almost All Bass)40 Incredible Images of the Surface of Mars NASA Says 2 Asteroids Will Safely Fly By Earth This WeekendScientists Discover Possible Interstellar Visitor