Satellites orbiting the Earth must occasionally be nudged to stay on the correct path. MIT scientists are developing a new rocket that could make this and other spacecraft maneuvers much less costly, a consideration of growing importance as more private companies start working in space.
The new system, called the Mini-Helicon Plasma Thruster, is much smaller than other rockets of its kind and runs on gases that are much less expensive than conventional propellants. As a result, it could slash fuel consumption by 10 times that of conventional systems used for the same applications, said Oleg Batishchev, a principal research scientist in the Department of Aeronautics and Astronautics and leader of the work.
The propulsion systems currently used for maintaining a satellite's orbit, pushing a spacecraft from one orbit to another, and otherwise maneuvering in space rely on chemical reactions that occur within the fuel, releasing energy that ultimately propels the object.
Although such systems have brought humans to the moon and are regularly used in a variety of other applications, they have limitations. For example, chemical rockets are expensive largely due to the amount of fuel they use.
As a result, engineers have been developing alternative, non-chemical rockets. In these, an external source of electrical energy is used to accelerate the propellant that provides the thrust for moving a craft through space.
Such non-chemical rockets have been successfully used by NASA and the European Space Agency in missions including NASA's Deep Space 1, which involved the flyby of a comet and asteroid.
But the field is still relatively new, and these advanced rockets are one focus of the MIT Space Propulsion Laboratory (SPL). "The Mini-Helicon is one exciting example of the sorts of thrusters one can devise using external electrical energy instead of the locked-in chemical energy. Others we in the SPL work on include Hall thrusters and Electrospray thrusters. This area tends to attract students with a strong physics background, because it sits at the intersection of physics and engineering, with ample room for invention," said Manuel Martinez-Sanchez, director of the SPL and a professor in the Department of Aeronautics and Astronautics.
The Mini-Helicon is the first rocket to run on nitrogen, the most abundant gas in our atmosphere.
It was conceived through work with former astronaut Franklin Chang-Diaz ScD '77 on a much larger, more powerful system developed by Chang-Diaz. Batishchev's team did a theoretical analysis showing that the first of three parts of the larger rocket could potentially be used alone for different applications.
The idea "was that a rocket based on the first stage [of Chang-Diaz's system] could be small and simple, for more economical applications," said Batishchev, who noted that the team's prototype would fit in a large shoe box.
Since then, 12 MIT students have worked on the Mini-Helicon, resulting in one PhD and four masters' theses to date. Batishchev notes, however, that it could be years before the technology can be used commercially, in part due to certification policies through NASA and other agencies.
The Mini-Helicon has three general parts: a quartz tube wrapped by a coiled antenna, with magnets surrounding both. The gas of interest is pumped into the quartz tube, where radio frequency power transmitted to the gas from the antenna turns the gas into a plasma, or electrically charged gas.
The magnets not only help produce the plasma, but also confine, guide, and accelerate it through the system. "The plasma beam exhausted from the tube is what gives us the thrust to propel the rocket," Batishchev said.
He noted that the exhaust velocity from the new rocket is some 10 times higher than the velocity from the average chemical rocket, so much less propellant is needed.
Work continues. Batishchev notes that last summer, for fun, his team built a plasma rocket based on a glass bottle (a stand-in for the quartz tube) and an aluminum can (the radio-frequency antenna), both of which previously held soft drinks. It worked. "This shows that this is a robust, simple design. So in principal, an even simpler design could be developed," he said.
This work was funded by the Air Force Research Laboratory.
Elizabeth Thomson | EurekAlert!
Further reports about: > Aeronautics > Astronautics > Mini-Helicon Plasma Thruster > NASA > Plasma > Space > Velocity > cheaper nudges > chemical reaction > chemical rocket > electrical energy > inexpensive gases > maneuvering in space > radio-frequency antenna > rockets > satellites > spacecraft maneuvers
Engineering team images tiny quasicrystals as they form
18.08.2017 | Cornell University
Astrophysicists explain the mysterious behavior of cosmic rays
18.08.2017 | Moscow Institute of Physics and Technology
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
21.08.2017 | Materials Sciences
21.08.2017 | Health and Medicine
21.08.2017 | Materials Sciences