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Among the many particles that resulted from this crash were bizarre objects called anti-hypertritons. Not only are these things antimatter, but they're also what's called strange matter. Where normal atomic nuclei are made of protons and neutrons (which are made of "up" quarks and "down" quarks), strange nuclei also have so-called Lambda particles that contain another flavor of quark called "strange" as well. These Lambda particles orbit around the protons and neutrons. If all that is a little much to straighten out, just think of anti-hypertritons as several kinds of weird. Though they normally don't exist on Earth, these particles may be hiding in the universe in very hot, dense places like the centers of some stars, and most likely were around when the universe was extremely young and energetic, and all the matter was packed into a very small, sweltering space. "This is the first time they've ever been created in a laboratory or a situation where they can be studied," said researcher Carl Gagliardi of Texas A&M University. "We don't have anti-nuclei sitting around on a shelf that we can use to put anti-strangeness into. Only a few anti-nuclei have been observed so far." These particles weren't around for too long, though – in fact, they didn't last long enough to collide with normal matter and annihilate. Instead they just decayed after a fraction of a billionth of a second. "That sounds like a really short time, but in fact on the nuclear clock it's actually a long time," Gagliardi told SPACE.com. "In that fraction of a billionth of a second that Lambda particle has already gone around the nucleus as many times as the Earth has gone around the sun since the solar system was created."

A mission trajectory study estimated that a VASIMR-powered spacecraft could reach the red planet within 40 days if it had a 200 megawatt power source. That's 1,000 times more power than what the current VASIMR prototype will use, although Ad Astra says that VASIMR can scale up to higher power sources. The real problem rests with current limitations in space power sources. Glover estimates that the Mars mission scenario would need a power source that can produce one kilowatt (kW) of power per kilogram (kg) of mass, or else the spacecraft could never reach the speeds required for a quick trip. Existing power sources fall woefully short of that ideal. Solar panels have a mass to power ratio of 20 kg/kW. The Pentagon's DARPA science lab hopes to develop solar panels that can achieve 7 kg/KW, and stretched lens arrays might reach 3 kg/KW, Glover said. That's good enough for VASIMR to transport cargo around low-Earth orbit and to the moon, but not to fly humans to Mars. Ad Astra sees nuclear power as the likeliest power source for a VASIMR-powered Mars mission, but the nuclear reactor that could do the job remains just a concept on paper. The U.S. only ever launched one nuclear reactor into space back in 1965, and it achieved just 50 kg/kW.