New Rocket Engine to Prove Solar Thermal Propulsion Isn’t Crazy
Engineers at the Johns Hopkins University Applied Physics Laboratory are prototyping a previously theoretical rocket design that could someday take spacecraft to interstellar space.
Their plan? Use heat from the sun, rather than combustion, to power a rocket engine.
Unlike a traditional engine that’s mounted on the rear end of a rocket, the experimental solar-powered engine takes the shape of a flat shield made from black carbon foam. The engine would double as a heat shield, protecting the probe from the sun’s powerful rays, while coils of tubing filled with hydrogen lying beneath the surface absorb heat from the sun.
The hydrogen expands, becomes pressurized, and then explodes out from a nozzle, generating thrust. The scientists call it solar thermal propulsion.
“From a physics standpoint, it’s hard for me to imagine anything that’s going to beat solar thermal propulsion in terms of efficiency,” Jason Benkoski, a materials scientist at the Applied Physics Laboratory (APL), told WIRED. “But can you keep it from exploding?”
Benkoski and his colleagues from APL and NASA recently shared their design online at the 3rd Annual Interstellar Probe Exploration Workshop. According to Benkoski’s calculations, a real-life version of the engine could be three times more efficient than the most advanced chemical combustion engines used in today’s rockets.
In 2019, NASA partnered with APL to kick off its Interstellar Probe study. The study will determine missions that could be launched next decade to study science outside our sun’s sphere of influence. Where the solar system ends and where interstellar space begins isn’t completely agreed upon, but one metric is the boundary where the sun’s magnetic fields and solar winds that make up the heliosphere can no longer be detected—what scientists call the heliopause.
APL is looking for a probe that can travel three times farther than the outermost reaches of the heliosphere in less than two decades time—a distance of 50 billion miles. To put that into perspective, let’s take a look at the current record holder of the farthest distance traveled.
In 2012, the Voyager 1 spacecraft became the first manmade object to leave the confines of our solar system. After lifting off from NASA’s Kennedy Space Center in 1977 aboard the Titan III rocket, the space probe embarked on a 2-year journey to Jupiter, where it was slingshotted by the gas giant’s massive gravity to continue its journey to Saturn, Uranus, and Neptune. (See the spacecraft’s full timeline here).
As of today, almost four decades since its launch, Voyager 1 is more than 14 billion miles from Earth and traveling at 38 thousand miles per hour (mph). The team at APL wants to shatter this record by accelerating its spacecraft to 200,000 mph and making the journey in half the time.
To pull it off, the spacecraft will have to accomplish another first: performing an Oberth maneuver a mere million miles from the fiery surface of the sun. Coined by one of the founders of modern rocketry, Hermann Oberth, the maneuver takes advantage of the gravitational pull of a celestial body by using a spacecraft’s engines to further accelerate its fall into a gravitational well, as seen here:
It’s a lot like running down a hill to gain momentum for the uphill. The steeper the hill, or the closer you get to a gravitational body like the sun, the easier it is to gain speed and maximize your energy. The problem? The sun is very, very hot.
In 2025, NASA’s Parker Solar Probe will perform its closest approach to the sun. It will come within 4 million miles of the sun’s surface, travel at speeds exceeding 400,000 mph, and experience temperatures as high as 2,500 degrees Fahrenheit. To fight off the giant nuclear furnace’s heat, NASA equipped its probe with a 4.5-inch-thick carbon-composite shield.
If APL plans to send its probe within a million miles of the sun, it will need to withstand temperatures around 4,500 degrees Fahrenheit for 2.5 hours as it performs its Oberth maneuver. That’s why NASA is finding new materials that could coat the spacecraft and reflect the sun’s heat. Additionally, the hydrogen flowing through the heat shield could act like a radiator, displacing the thermal energy as propellant.
“We want to make a spacecraft that will go faster, further, and get closer to the sun than anything has ever done before,” Benkoski told WIRED. “It’s like the hardest thing you could possibly do.”
Benksoski and his colleagues at APL plan to submit a report on findings from their experimental rocket design next year.
See more here: popularmechanics.com
Header image: Getty Images
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Jasper's Farm
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Why can’t the achieve the same effect with reflector shields in an earth orbit that concentrate the power of the sun into a small area, much the way solar farms do?
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Herb Rose
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Providing money for this hair brained idea is what’s crazy.
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Ken Hughes
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According to the description given, there is no oxygen to burn the hydrogen with. No matter how high the temperature, hydrogen will never “explode” on its own. It may leach into the metal of the pressure container though and rapidly produce hydrogen embrittlement. Without more detailed information on the design, this looks like a scam.
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bobarance
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I find it troubling that this website is smart enough to question the Plandemic, Global Warming and other obvious frauds, but still is under the mass delusion that space exists. No space, no globe, no such thing as gravity or galaxies, planets, nuke furnaces millions of light years away. NASA is a fraud. For the love of Pete, wake up! Use your senses! Do some experiments and discover the Flat Earth you mindless sheep.
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very old white guy
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The observable eludes you.
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bobarance
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What have you actually observed old white simpleton? What a hypocrite! You come here and read stories that question the narrative about Covid and other obvious lies yet you steadfastly cling like an impudent child to the “final frontier”. So “they” lie about most things but not your fiercely protected Universe eh? That must be off limits right? What observable things are you referring to? Would you care to debate or do you relish your ignorance too much?
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Purple People Eater.
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Wickedlington Bob.
I have been trying like hell to figure out what the moon is. I can not figure it.
Any help would be appreciated. Cool. Cool, cool.
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bobarance
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I don’t exactly know what the Moon is either. I do not believe it is a rock 238,000 miles away that can be landed on by a rocket ship. Only one side of this so called “Moon” is ever observable ever. How can anyone say it’s a globular shape when it just as easily could be a disk or even a hole in the sky? Isn’t science based on provable, demonstrate-able, evidence that can be repeated? Nobody has ever seen another side of the Moon. So how does that scientifically prove it’s a ball? And how about it’s distance from the earth? NASA claims 238,000 miles. How does the lay person measure that? And how do they?
At night under a full Moon, the Moon light appears to be created by the Moon itself. It’s bright enough to create shadows. If you place a metal pan in this Moon light it typically is 3 to 5 degrees cooler than the same metal pan in the shade. How can that be? NASA claims the Full Moon is reflecting the light of the Sun. If that were true wouldn’t the light be warmer than the shade? Yet it’s not. Anyone can duplicate this experiment. Just go get a 15 dollar laser thermometer and a pie pan. Oh and one more thing. I have often observed the Moon in the daytime sky with the Sun shining brightly. I look to the Sun and then the Moon and the portion of the Moon that is illuminated does not match the angle that the Sun is allegedly striking it.
I believe that the Sun and Moon are luminaries that independently provide light. I do not believe that the Sun is a Nuke furnace in space 93 million miles away. And I do not believe that the Moon is a rock in “space” 238,000 miles away.
Bonus. I have observed a couple of eclipses now and have discovered some strange things. I see the Sun dim and be eclipsed then re-gain it’s previous shine. Science says it’s the Moon moving between my position on the Earth and the Sun above. Funny thing is I never saw the Moon in the sky moving in front of the Sun nor moving away after the eclipse. Just the effect of the temporary eclipse. How is that possible? Perhaps that is why “science” warns everyone each time to never look at the eclipse! We might just figure out that they are full of it.
Herb Rose
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Hi Bobarance,
When you speak of the pan being in the shade are you saying that in the shade of the moon light the pan is cooler than exposed to the moon light or in the shade of sunlight? I do not believe being in the shade of moonlight would make the pan warmer but I do believe that the reflected light from the moon would make the pan warmer than receiving no light from the sun.
Do you believe the sun and the moon are the same size since the moon covers the sun completely during a full eclipse? How could a hole in the sky cause an eclipse?) Do you believe that the tides are caused by the moon and sun? If they are the same size wouldn’t there be very little tide during a full moon and a double tide during a new moon?
I think your problem is determining a correct point of reference when there are multiple motions involved. If you are in a car traveling at 100 mph you do not feel you are moving. If you open a window and put your hand out you will feel a 100 mph wind and yet the leaves on the trees are not moving. The proper reference point for observations is at the center of the controlling energy field (gravity) If you are at the equator traveling at 1000 mph laterally or at the North pole traveling 0 mph laterally your reference point is the center of the Earth and your velocity is the same as all the things around you.
Herb
Howdy
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There are no poles on a flat Earth, Herb.
Jerry Krause
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Hi Herb and other PSI Readers,
Good comments Herb but you didn’t refer to Bobarance’s comment: “If you place a metal pan in this Moon light it typically is 3 to 5 degrees cooler than the same metal pan in the shade. ” Here, like a good SCIENTIST, he is refers to an observation; which I believe is true and hence deserves an explanation.
I will leave it to you, Herb, to explain to him (and other PSI Readers) the cause of what he has observed.
Have a good day, Jerry
Herb Rose
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Hi Howdy,
Sorry I forgot. If you travel north or south you will fall off the edge of the Earth. If you travel east or west you will eventually arrive at your starting point. The Earth is a rotating cylinder.
Herb
Howdy
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You can’t fall off the edge, Herb, and they have a reason why, which is, there’s an ice wall surrounding the disk (the south pole) that is patrolled by soldiers, so you can’t climb up.
I guess that’s why special permission is needed to go there.
Regarding the Moon not being a rock. David Ike says it is hollow, and contains a relay transmitter for Saturn transmissions I believe? We don’t exist as we think, but are actually ‘consciousness’, being force fed this reality (from the Moon) to keep us oppressed and controlled…..
Purple People Eater
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Do not forget the high security area where there is a gap in the ice wall where they let groups through to go bungee jumping off the edge.
Plus on the far side of the moon are some people waiting for us to show up. They are called “Pink Floyd “.
Herb Rose
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Hi Purple,
Since you have one eye, one horn, and can fly why don’y you go up there and check it out? We await your report on the real evidence.
Herb
Howdy
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I’ve used my senses Bobarance.
Self-observed with my own eyes, and deduced via common sense, I watched a ship moving away from me into the distance. Did it grow smaller as time passed until it was a tiny dot, as would be expected of a flat surface? No, It appeared to sink. This is due to the curvature of the Earth.
As far as the Bible is concerned:
https://eternal-productions.org/PDFS/articles/Does%20the%20Bible%20Teach%20a%20Spherical%20Earth.pdf
BAHHHHHH!!
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bobarance
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A ship eh? So the earth is obviously a ball spinning through space because you allegedly observed a ship appear to sink? Well excuse me genius! I guess that settles it. Perhaps you should try that again with a telescope or a strong pair of binoculars. You will see that ship miraculously re-appear once again. It is not going over the curve because there is no curve. The earth is demonstrably flat.
Listen, they lie about covid, disease, wars, terrorism, shootings, “global warming” (2 lies in that title alone), central banking, health, weather, fires, history, education, pretty much everything. Why cling to your precious globe? Free yourself!
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Howdy
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“So the earth is obviously a ball spinning through space because you allegedly observed a ship appear to sink?”
I never said anything about a ball, or spinning through space. You did.
BTW, what about the Bible reference?
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Jerry Krause
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Hi PSI Readers,
What an opportunity to read first hand what Aristotle and his fellow philosophers were debating (and ignoring what was plainly seen) as they concluded” the earth stands still, bodies twice as heavy fall twice as at a constant speed (rate), that the elements of matter were earth, water, air and fire, that matter was endless divisible so there was nothing like an atom!!! This is a list of what really intelligent people have done and still do!!!
Have a good day, Jerry
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Jerry Krause
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Hi Herb and other PSI Readers,
Herb, you wrote:’ “The Earth is a rotating cylinder.” Where did you get that from? For I seem to remember that I wrote that several times here at PSI. And I thought I had an original idea. I’m going to wait until you tell us a reason why this is a better model than the near sphere of the globe. For I want to be sure that I wasn’t the first to suggest that a rotating cylinder is a better model.
Have a good day, Jerry
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