— SpaceX is poised to make history by launching the world's fourth electric car into space.
Years in the making, the commercial spaceflight company is preparing to launch its first Falcon Heavy rocket, which as its name implies, is a heavy-lift booster built from a core stage and two of SpaceX's Falcon 9 recoverable rockets. According to SpaceX, when the Falcon Heavy lifts off, it will be "the most powerful operational rocket in the world by a factor of two." Only NASA's Saturn V rocket, which carried six crews — and three electric cars — to the moon almost 50 years ago, could deliver more payload to orbit. (The space shuttle had more thrust at launch than the Falcon Heavy, but had a lower payload capacity.) Even though the Falcon Heavy is based on the design of the proven (and flight-proven, or reflown) Falcon 9, its configuration is new and so carries new risks. The rocket's 27 Merlin engines must fire in unison and the two side mounted boosters need to separate from the core — something SpaceX has never done in flight. "Going through the sound barrier, you get supersonic shockwaves. You could have some shockwave impingement, or where two shockwaves interact and amplify the effect, that could cause a failure as it goes transonic," said Elon Musk, SpaceX's CEO and chief designer, in a call with with reporters on Monday (Feb. 5) "Then around Max-Q, which is maximum dynamic air pressure — that is when the force on the rocket is the greatest — and that's possibly where it could fail as well." "We're worried about ice potentially falling off the upper stage onto the nose cones of the side boosters," Musk continued. "That would be like a cannon ball coming through the nose cone. And then the separation system has not been tested in flight. We have tested everything that we could think of for the separation of those side boosters on the ground, but this is the first time it has to operate in flight." As such, Falcon Heavy's success on its maiden mission is not a sure thing and so placing a satellite or some other operational payload on board wasn't considered a prudent move. Test flights typically carry a mass simulator, taking the place of the payload in the form dead weight, like concrete or steel blocks. "That seemed extremely boring," Musk wrote on Twitter in December, just before revealing what would top the rocket. "We decided to send something unusual, something that made us feel," he said. "The payload will be an original Tesla Roadster, playing [the song] 'Space Oddity,' on a billion-year elliptic Mars orbit." More specifically, Musk, who is also the CEO and product architect at Telsa, said it was his personal "midnight cherry" Roadster.
Photographs of the electric car taken prior to it being encapsulated in its protective fairing for launch revealed a few more details.
Strapped into the driver's seat is a mannequin dressed in a spacesuit of the same black and white style as SpaceX designed for NASA astronauts to soon wear for flights on the company's Dragon spacecraft to and from the International Space Station. Musk referred to the driver as "Starman" — another nod to the late David Bowie — in a tweet on Monday (Feb. 5). "If you look closely you'll see a little easter egg on the dashboard," Musk teased, talking to reporters. The photos appears to show a miniature version of the Roadster, complete with its own tiny Starman, on the dash of the convertible. The (full-size) car is mounted atop the Falcon Heavy's second stage such that its front is higher than its rear. The second stage will fire its single Merlin engine three times, first to place the it and Tesla into space, then to demonstrate the Heavy's ability to insert satellites directly into geosynchronous Earth orbit and then finally, if all goes to plan, to thrust the Roadster into deep space. Between the second and third burns, the Roadster will coast for six hours, passing in and out of the Van Allen belts, a concentrated region of radiation that surrounds Earth. "We're going to be testing something on this flight which we've never done before, a six hour coast in deep space that's going to go through the Van Allen belts," said Musk. "So, it is going to get whacked [by radiation] pretty hard." "The fuel [for the second stage] could freeze and the oxygen [for the engine] could vaporize, all of which could inhibit the third burn which is necessary for trans-Mars injection," he said. If the stage survives the "grand tour" of the Van Allen belts and successfully fires its engine for a third time, then the Tesla will leave Earth on a journey to out where Mars circles the Sun. "It will go out to Mars orbit," said Musk, "about 400 million kilometers from Earth, about 250 to 270 million miles, and be doing 11 kilometers per second [7 miles per second]." "It is going to be in a precessing elliptical orbit, with one part of the ellipse being in Earth orbit and the other part being in Mars orbit. So essentially, it will be an Earth-Mars cycler and we estimate it will be in that orbit for several million years, maybe in excess of a billion years, and at times it will come extremely close to Mars and there is a tiny, tiny chance it will hit Mars," he said, adding that the chances of an impact with the Red Planet was "extremely tiny." Musk's Tesla Roadster will be the first car that was built to be driven on Earth to be launched into space, but for the first car to leave the planet, you need to look back almost half a century. The first and last time that a car ventured beyond Earth was aboard NASA's threelast Apollo missions to the moon. The Lunar Roving Vehicle (LRV, or lunar rover) helped expand the ground that the Apollo astronauts could cover while exploring the lunar surface. Built by Boeing and General Motors, the latter providing the rover's wheels, motor and suspension, the Apollo-era car drew its power from the rover's two silver-zinc potassium hydroxide non-rechargeable batteries and had a range of 57 miles (92 kilometers). By comparison, the Tesla Roadster uses a lithium-ion power pack with a range of 244 miles (393 km). But the Roadster won't be driving on its space voyage. It will however, be sending back data, and with luck, imagery of its departure from Earth. "There are three cameras on the Roadster. They really should provide some epic views, if they work and everything goes well," said Musk. |
SpaceX's first Falcon Heavy rocket stands poised for launch on Pad 39A at NASA's
Kennedy Space Center in Florida. |
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