NASA invests $67 million into solar electric propulsion for deep space exploration

Emily Calandrelli (@TheSpaceGal)

NASA has selected Aerojet Rocketdyne for a $67 million contract to develop an advanced Solar Electric Propulsion (SEP) system for future deep-space missions.

In a press release, NASA stated that the propulsion system could be used on robotic missions to an asteroid and in other missions related to their Journey to Mars program.

Compared to chemical propulsion (the type of propulsion that rockets use to escape Earth’s gravity well and reach orbit), SEP has lower thrust but is more fuel-efficient and can provide thrust for longer periods of time. For these reasons, SEP works well in the vacuum of space, particularly on spacecraft with long mission lifetimes.

A Hall thruster tested at NASA Glenn Research Center/ Image courtesy of NASA

SEP engines provide thrust by converting solar energy into electricity and using that electricity to accelerate ionized propellant at extremely high speeds. The iconic blue glow from a SEP thruster is created from photons released by the ions as they lose energy upon leaving the engine.

NASA has been working on SEP technology since the 1950s and they’ve used SEP on prior missions like the Dawn spacecraft, which is currently in orbit around the dwarf planet Ceres and is the first spacecraft to orbit around two extraterrestrial bodies.

Illustration of the Dawn spacecraft with its SEP system / Image courtesy of NASA

Under the new contract, NASA hopes to double the thrust capability compared to current electric propulsion systems and increase the fuel efficiency by 10 times the current chemical propulsion.

One challenge with deep-space missions that use SEP is that as you travel deeper into the solar system (farther away from the sun), it becomes more difficult to effectively capture light from the sun to power the spacecraft. Because of this, NASA stated its current SEP research is funded in parallel with work to advance solar array technology.

During the 36-month contract, Aerojet Rocketdyne is responsible for constructing, testing and delivering an SEP product for testing and evaluation. Eventually, the goal is to have Aerojet Rocketdyne deliver four electric propulsion units that will fly in space.

“Through this contract, NASA will be developing advanced electric propulsion elements for initial spaceflight applications, which will pave the way for an advanced solar electric propulsion demonstration mission by the end of the decade.” Steve Jurczyk, associate administrator of NASA’s Space Technology Mission Directorate

In addition to this particular electric propulsion contract, Aerojet Rocketdyne is responsible for the chemical propulsion — the RS-25 engines — for NASA’s Space Launch System, the rocket designed to be used on missions related to NASA’s Journey to Mars initiative.

Illustration of NASA's Asteroid Redirect Mission using SEP / Image courtesy of NASA

Aerojet Rocketdyne’s current contract is part of NASA’s overall push to advance SEP systems. NASA plans to test the largest and most advanced SEP system ever used in space on their Asteroid Redirect Mission, which is designed to capture an asteroid and place it in orbit around the moon. That mission is currently slated for the mid-2020s.

 

‘Dr Frankenstein’ ready to perform first head transplant by 2017

A controversial surgeon is preparing to carry out the first ever whole head transplant by the end of 2017 after “successful” experiments on monkeys and mice.

Neurosurgeon Sergio Canavero introduced the strategy in 2013 and has been touting his experiments since.

In 2015, the 51-year-old presented at the American Academy of Neurological and Orthopaedic Surgeons’s 39th annual conference, where his speech about the ambitious procedure served as the keynote talk.

Earlier this year, Dr Canavero told New Scientist he had been conducting a series of experiments on animals and human cadavers with the help of scientists in China and South Korea.

“I would say we have plenty of data to go on,” Dr Canavero said.

“It’s important that people stop thinking this is impossible.”

Dr Canavero is working with Xiaoping Ren from Harbin Medical University in China.

According to the publication, Mr Ren has already performed a monkey head transplant and more than 1000 head transplants on mice.


Valery Spiridonov (centre) suffers from Werdnig-Hoffman disease and has volunteered to be the first person to undergo a head transplant under Dr. Canavero’s hands. Photo: Maxim Zmeyev/REUTERS

Dr Canavero’s first patient is Russian program manager, Valery Spiridonov, who is suffering from the rare muscular atrophy disorder Werdnig-Hoffman disease.

The 31-year-old volunteered for the transplant and says that he’s willing to risk death to escape his disease.

His transplant will be done in a vegetative state and is set to take place at Harbin Medical University in China.

 

The two-part procedure is composed of HEAVEN (head anastomosis venture) and Gemini (the subsequent spinal cord fusion).

The whole process involves 36 hours, 150 people (doctors, nurses, technicians, psychologists, and virtual reality engineers), and around $20 million.

According to Dr Canavero, there will be two surgical teams working on the Russian patient at the same time.

One will focus on the Mr Spiridonov, the living patient, while the other will focus on a donor’s body.

The donor will be brain-dead and selected based on height, build, and immunotype.