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Originally published 1995
Authors Marcel den Dikken
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Particles are words that do not change their form through inflection and do not fit easily into the established system of parts of speech. Examples include the negative particle "not," the infinitival particle "to" (as in "to go"), and do and let in "do tell me" and "let's go. " . . .

New engine tech might be faster us to Mars

Feb 16,2020 4:55 am

Mars Base Camp: a concept of the Orbit Outpost on the Red Planet by Lockheed Martin

If we ever make regular trips from the earth to Mars and other distant trip, maybe we need new types of engines. Engineers are exploring new technologies that could help us to traverse the Solar System in much less time.

Because the orbit of Mars and earth take around The Sun , the distance between them varies between 54. 6 million kilometers and 401 million km.

missions will be launched to Mars when the two planets make an approximation. During one of these approaches, it takes Nine Months to spread to Mars with chemical Rockets - the shape of the drive far.

This is to spend a long time for someone else to travel. But engineers, including those at the U.S. Space Agency (Nasa), working with industrial partners on the development of faster methods to get us there.

So, what are some of The Most promising technologies?

Solar electric propulsion solar electric propulsion could be used to send cargo to Mars ahead of a human task. This would ensure that the equipment and supplies were ready and waiting for the astronauts when they came up with chemical Rockets , according to Dr. Jeff Sheehy , chief engineer in the Nasa Space Technology Mission Directorate.

Using solar-electric propulsion, large solar sails unfurl to catch The Sun 's energy that is then converted to electricity. These forces are so-called Hall thruster.

There are advantages and disadvantages. On The Other hand, you need far less fuel, so the space ship, it will be easier. But it is also your vehicle takes longer to get there.

", to the payload, we would have to, it would probably be between the two 2. To says 5 years to get us there," Dr. Sheehy the Bbc .

Aerojet Rocketdyne is on a Hall thruster for the lunar Gateway "For the type of Outpost that we need to build on Mars for The Crew to survive in the situation for months, and the vehicles they would have a lot of cargo. "

Aerojet Rocketdyne is on a Hall thruster for The Gateway , a proposal for a space station in lunar orbit.

"Solar is The Best , because we know we can expand," Joe Cassidy , executive director of Aerojet Rocketdyne 's space division, she explains.

"We already have this to fly today on communications satellites. The Power -stage, we fly today, is 10-15 kW (kilowatts), and what we seek to do, with The Gateway to scale up to something larger than 50kW. "

Mr Cassidy spoke Aerojet Rocketdyne 's Hall thruster is a lot of driving More fuel-efficient than one with Liquid Hydrogen and oxygen Rocket Engine .

But in a good way, the access to space cheaper would be less starts, he explains.

"I think that solar-electric propulsion is a very Good Technology , the use of xenon as a fuel. But the two major disadvantages are the time it takes to get there, and the size of the solar arrays," says Tim Cichan, a manned space architect at the aerospace giant Lockheed Martin .

Dale Thomas , professor and eminent scholar in systems engineering at the University of Alabama in Huntsville (UAH) is consistent.

"Solar-electric-works well for small payloads, but we still have problems to scale it," he says of the Bbc .

He thinks it could is an important alternative technology, if the technical challenges can be solved. But now, he says, there are other better options, such as nuclear-thermal-electric drive.

- Nuclear thermal-electric propulsion another idea is raise the use of chemical rocket from earth and land on Mars . But for The Middle part of the trip, some engineers propose using something called the nuclear thermal electric propulsion.

The Orion crew module, docking a Gateway in the lunar orbit could be sent astronauts to The Gateway of the Nasa Orion capsule. The Orion crew capsule would dock with a transfer vehicle.

Once Orion was associated with the transfer of The Vehicle , a nuclear electric rocket would be used to The Crew capsule and the transport module to Mars , where they connect with a Mars orbiter and lander waiting in orbit of Mars .

In a nuclear thermal electric rocket, a small Nuclear Reactor hydrogen is heated liquid. The gaseous form of the element expands and shoots out of the engine.

"If we transit time [Mars ] cut down from 30 to 60 days, it improves the radiation exposure to The Crew ," says Mr. Cassidy. "We're looking at nuclear thermal as a key technology, because they can enable faster running times. "

Dale Thomas , together with UAH, has a study contract with Nasa to design a space rocket with a nuclear thermal engine He thinks nuclear thermal electric is the next new engine technology ready for use.

"Some of the tracks we run in my lab, we can months of the term of up to three, this is still a very long way, but it's about a third of the time is required in the chemical drive to get us there," he says.

in space, astronauts are exposed to radiation. Some of these would not increase in the space industry fear nuclear thermal propulsion is that the risk is Boeing so keen on nuclear-thermal propulsion, because they might have to worry about the effects of a Nuclear Reactor , to astronauts.

Mr. Thomas disagrees: "This is a misunderstanding. Of hydrogen as a fuel is a large weather cabin.

"The Team is at one end of The Vehicle and the engine at The Other end. As such, the preliminary estimates show that The Crew More dose from cosmic radiation to get radiation than the nuclear-thermal engine. "

he admits, However, a disadvantage of the technology, the inability to simply test it on the earth.

But Nasa is developing a ground-test apparatus that scrubs the exhaust to remove radio active Particles - making-soil-tests.

Electric ion propulsion is another idea electric ion drive. These produce Thrust by the acceleration of ions, i.e. charged atoms or molecules - with electricity.

ion propulsion is already used to power satellites in space. But they produce only a small Thrust is More like the force of the Hairdryer - and therefore have a low acceleration. But given the time, you can reach high speeds.

Ad Astra says, it works on a type of engine called the Vasimr, to ionise the radio waves, and to accelerate heat, fuel, And Then a magnetic field and the resulting soup of Particles - the plasma. The Vasimr is designed to provide much More Thrust than a standard ion engine can produce.

required current can be generated in various ways. But for sending people to Mars , The Team with a Nuclear Reactor would. The Vasimr would use solar electric for smaller payloads.

Ad Astra president and CEO Franklin Chang-Diaz, a former Nasa astronaut, says need manned missions to Mars in less than Nine Months , in the ideal case.

Former Nasa astronaut Franklin Chang-Diaz, the Red Planet is much heavier than on The Moon , he says.

"will go to The Solution quickly," said Mr Chang Diaz, the Bbc says. "For a space ship that would weigh 400-600 tons, with a capacity of 200 MW (megawatts) you can get to Mars in 39 days. "

Dale Thomas believes the scaling of the Vasimr will be difficult, as the performance of a lawn mower to a rocket to The Moon . But the technology is promising.

"If, or perhaps I should say, if Ad Astra can solve the technical challenges Vasimr seems to be The Best choice for electric actuators in the human-ferrying space ship scale," Mr Thomas said.

"says The Physics that it should work. However, I must point out that Vasimr is still in development, in the laboratory; it is a long way from the flight-ready for any size order. "

Mr Chang Diaz does not see a problem with the scaling, it's just that there is currently no market for a 10 MW engine, so Ad Astra stick with 200kW.

"We have a market for the 200kW Motor, there is a lot of activity in low-Earth orbit and near The Moon to move in cis-to-earth satellite," says Mr Chang Diaz.

Lockheed Martin is also thinking of the Vasimr is a promising technology, but it is the focus on solar-electric propulsion.

The case for the chemical Rockets , Although the new technologies are interesting, veteran space players Lockheed Martin and Boeing both think that liquid chemical rocket must be the basis of any human mission to Mars .

Lockheed Martin says, we already have the technology we need for Mars , and the chemical Rockets are a proven technology, and worked in all of the Apollo missions.

"We already have the technology to take us to Mars Today ," says Mr. Cichan, the former System Architect for Orion .

graphic: The engines of The Core stage of the SLS, the Space Shuttle "There are some technical challenges, but it is really about the technology we have, build the systems and the experience in flying In Deep space, this is The Work before us, as well as the development of technologies, the leading the way in The Future . "

hydrogen upper stages and launchers have been available since the 1960s, and you have emphasized a high rate of success, he.

"Nasa's Space Launch System (SLS) has four Liquid Hydrogen -and oxygen-RS-25 Rocket Engine ," Rob Broeren, a Boeing rocket propulsion specialist, says the Bbc .



mars, the moon, nasa, boeing

Source of news: bbc.com

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