A slingshot around the sun would make a spaceship the fastest

NASA is very interested in developing a propulsion system to allow spaceships to go faster. We have many times reported various ideas in support of that goal, and many of the most successful ones have made good use of the sun’s gravity, usually in the orbiting sling, as Jupiter does. at this time.

But, there are still big obstacles when doing so, not least of which is the energy that radiates from the sun to blow anything close to using a gravitational assist. That is the problem of a project supported by NASA’s Institute for Advanced Concepts (NIAC) and managed by Jason Benkoski, of the Lawrence Livermore National Laboratory, which is trying to solve it.

The project was awarded the NIAC Phase I grant in 2022, based on the integration of two different systems – a heat shield and a heating system. According to the project’s final report, the combination of those two technologies will allow a spacecraft to perform the so-called Oberth maneuver in the sun.

In this orbital maneuver, a spaceship takes advantage of the sun’s gravity to catapult itself at high speeds in its intended direction. It is similar to the sudiver technology discussed in other articles.

So what makes this project unique? The heat shield is one thing—Dr. Benkoski and his team developed something that can last up to 2700 K. Although it is nowhere near the temperature of the sun, which can reach 5800 K, enough to get close enough, opening up an inability for aircraft carriers to use an Oberth trick in the first place.

Samples of items with these hot items have already been produced. However, more research is needed to understand if it is cut out for the airliner. And a heat shield alone is not enough to get the job done—an airplane must also have a system that can withstand that heat.

A solar heating system could. These systems use the sun’s energy to power their own catalysts and then expel the gases outside to produce energy, which is a part of needed as an Oberth trick. There are many different types of fuel that can be useful for such a system, and a large part of the research in the Phase I project looked at the different costs/effectiveness of each.

Hydrogen is one of the most common fuels used for solar heating. Although it is clean, it requires an extensive cryogenic process to store hydrogen because it is hot enough to be used as an injection. In the end, its trade-offs were negligible compared to the biological factors evaluated during the project.

Lithium hydride was the surprise winner for the fuel that could achieve the fastest escape velocity. Calculations show that this could result in a velocity of more than 12 AU/year. However, there are complications in the storage and handling of oil.

Dr. Benkoski settled on a common fuel as the overall winner of the experiment he created—methane. Although it usually has a slower final velocity than lithium hydride, its final velocity is still respectable above 10 AU/year. It also eliminates many of the obstacles to storing other fuels, such as the cryogenics required to store hydrogen.

There are some problems, though – the maximum speed is only 1.7 times more than what could be done with a booster from Jupiter, which does not need all the heat shield.

There are other drawbacks to that, though, like the direction the spacecraft can travel is limited by where Jupiter is at. other interests. A solar flare, on the other hand, can reach anywhere in the sun and beyond with a properly controlled burn.

As stated by Dr. Benkoski in the final report, he made many assumptions when making his model calculations, including that the system will be able to use technology that has already been developed instead of speculation that can significantly affect the results.

For now, it seems that NASA has not chosen this project to go to Phase II, and it is not clear what future work is planned for expansion. If nothing else, it’s a step toward understanding what it takes to actually send spacecraft beyond the sun and into deep space at speeds faster than anyone else’s. first things first. Due to NASA’s continued attention to this topic, no doubt, one day, one of the missions will be successful in doing so.