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(Phys.org)—A small team of researchers at Harvard University who are part of the Breakthrough Starshot team has been testing the likely damage to an interstellar spacecraft traveling at approximately one-fifth the speed of light as it makes its way to the Alpha Centauri star system. As they note in a paper describing their testing and results, which was uploaded to the arXiv preprint server, such damage could be catastrophic, but they believe they have a solution.

Earlier this year, Russian billionaire Yuri Milner announced to the world that he wants to send a probe to the Alpha Centauri star system—he put up $100 million of his own money to get the ball rolling on what is expected to be a multi-billion-dollar effort. At the time of the announcement, Milner told the press that his team of advisors had identified 20 main challenges that would have to be overcome in order for such a mission to be a success. In this new effort, the researchers have addressed one of those challenges—assessing the likely damage to the craft due to space dust and gases, and offering solutions to the problem.

The preliminary working design of a able to travel at ∼0.2c is little more than a circuit board that has come to be known as a wafersat—it would be attached to a light sail that would be the target of a laser sent from Earth to push it during the initial part of the journey. The wavsat would be made mostly of graphite and quartz. Thus, the researchers focused the bulk of their testing on these two materials. They discovered that particles of hit by the craft would mostly come in the form of collections of heavy atoms rather than particles—those collisions would cause two problems. The first would be the creation of pits on the surface of the craft, which would result in loss of material (up to 30 percent of the entire craft might be lost).

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China has unveiled illustrations of a Mars probe and rover it aims to send to the Red Planet at the end of the decade in a mission that faces “unprecedented” challenges, state media said on Wednesday.

China, which is pouring billions into its space programme and working to catch up with the US and Europe, announced in April it aims to send a spacecraft “around 2020” to orbit Mars, land and deploy the rover.

Zhang Rongqiao, chief architect of the project, said Tuesday they were targeting July or August of that year for the launch, the Xinhua news agency reported.

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As for the maximum distance the train could journey, “There is no limit,” Bombardier asserts. He reckons the first ship would shuttle cargo and travelers between Earth and the Moon—a trip that would take roughly seven hours to complete at the ideal speed of 15 km/s. “The Moon will serve as a launching pad for other projects, because it is easier to assemble and build this kind of train in the absence of gravity,” he says. “And Mars seems to be a good candidate for the next phase, especially if we can terraform it.”

Though intriguing, the notion begs many questions, and likely won’t be viable for eons. “Obviously there is a lot to consider,” the designer admits. “The general purpose here is to devise a system to transport minerals, materials, and humans from one place to the other in our solar system. Solar Express is a basic idea, and we would like to know how we could improve it.”

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# Venus # OxygenVenus’ ‘Twin Planet’ Could Still Have Oxygen, Scientists Say : Nine months ago, astronomers announced that they were able to discover a planet that is said to be a twin to Venus. Today, it seems that a new study raises the possibility of the said planet to have oxygen in its atmosphere – don’t mistake it for the next livable planet though – it is said to have hellish temperatures, which automatically rules out the possibility of life.

Dubbed the GJ 1132b, IFL Science noted that it is larger than Earth in size and mass. Temperature-wise, it is considerably hot at 120 to 320 degrees Celsius, but it is still considered cooler than most of the rocky planets previously detected.

The GJ 1132b orbits around 2.2 million kilometers from its star, about 1.5 percent of the Earth-Sun distance. Its parental star, the GJ 1132, is a red dwarf planet just a fifth of the sun’s mass, but is more exposed to light than the earth. While undoubtedly hot, wide estimates of its temperature show that it could reflect a Venus-style runaway greenhouse effect.

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Wild stuff.


Somewhere on the other side of the sun, almost directly opposite to Earth, a NASA spacecraft has drifted aimlessly through the void since Oct. 1, 2014, unable to establish contact with our planet.

At least that was the depressing situation until Sunday night.

In a statement posted Monday (scroll down for the full version), the space agency says it has finally contacted the STEREO-B solar observatory — an identical twin of another sun-monitoring robot, called STEREO-A — after nearly 2 years of effort.

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The first stage launches the rocket off of the pad and continues firing for about four minutes. Once the first stage is out of fuel, it separates, and if it’s a SpaceX Falcon 9, flies back home to be reused. If it’s anything else, including the Atlas V, the first stage crash lands in the ocean and sinks. Meanwhile, the second stage fires up its own engine (or engines) to boost the payload the rest of the way into orbit. On the Atlas V, the second stage is called Centaur. Once Centaur gets its payload where it needs to go, it separates, and then suicides down into Earth’s atmosphere.

Getting a payload into space is so expensive because you have to build up this huge and complicated rocket, with engines and guidance systems and fuel tanks and stuff, and then you basically use it for like 15 minutes and throw it all away. This is why SpaceX is trying so hard to recover the first stage of the Falcon 9. But what about the second stage? You’ve got a whole bunch of hardware that made it to orbit, and when getting stuff to orbit costs something like $2,500 per kilogram, you then tell it to go it burn itself up in the atmosphere, because otherwise it’s just useless space junk.

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