When researching propulsion methods in space, the concept of “solar sail” comes up, which is an incomprehensible idea.
This is a concept where “solar energy is likened to wind and used for propulsion,” but I cannot understand it.
The concept of a magnetic sail also comes up.
Since it is impossible to understand these things by facing them head-on, let’s start by imagining something familiar.
Thinking from familiar things (this approach is wrong)
If you have seen Top Gun: Maverick, you may remember a scene where a sailboat sails on the sea.
Don’t forget the parachute.
Kite flying is another example.
If we apply this principle…
We would like to say that, but this is a trap.
First of all, a solar sail does not physically receive the solar wind from solar flares and move forward.
This is a big mistake at this point.
A solar sail moves through the reactive force generated by the reflection of particles of light, which are photons.
It moves not by physical force, but by light. I don’t understand the meaning.
“What is a Photon?”
Well, hold on. It’s not light, it’s a “photon.”
Historical Background of Understanding “Elementary Particles”
It seems like it’s going to get quite lengthy just with this, and I’m getting tired of it, but I’ll pursue it out of personal interest.
I found a description that says “one of the 17 elementary particles included in the Standard Model,” so let’s delve deeper into it.
First of all, an elementary particle is the “smallest unit that makes up matter.”
As physics developed, the atomic nucleus was discovered, and it was found that the atomic nucleus is composed of protons and neutrons, and smaller “elementary particles” were discovered than protons.
That’s how it emerged in this context.
I spent several hours researching various things, but it became too complicated and I got confused, so I’ll reorganize the details when I feel like it.
Does the Higgs Particle Give Mass to Elementary Particles? (Unrelated to Solar Sail)
Due to the propulsion principle of the solar sail, I’m curious about the existence of the Higgs particle, which is said to “give mass to elementary particles.”
However, the Higgs particle seems to be more of an entity that “brings elementary particles together and applies brakes” rather than anything else.
Regarding this, it is nicely summarized in the article “The Story of the Encounter between Space and Particles,” so I recommend reading it for a clearer understanding.
Quotation of a Clear Explanation Found After Persistent Research
Amidst my lack of understanding, I searched for every possible term and visited as many websites as I could, and as a result, I found a description that is easy to understand for anyone.
I would like you to refrain from explaining the mechanism of the solar sail in the form of quoting it. When the topic of elementary particles is brought in, it goes beyond the realm of comprehension…
RIKEN’s “ Realization of Sound Waves Controlled by Pressure”,” Electromagnetic waves such as light have radiation pressure. and is known to impart momentum to an object when reflected by it.“.
Also, let me quote from a certain page of JAXA.
Actually, we are under the pressure of light on a regular basis.
I am receiving power from both bright walls and hot stoves. Solar radiation pressure is the force generated when photons flying from the sun collide with the surface of the spacecraft, such as solar panels and antennas. Get bigger.
In a yacht, the photons are the wind, and the solar panels and antennas are the sails.
This force is very weak, about 1/100th of that of electric propulsion, but more than 10 times greater than Itokawa’s gravity at the gate position.
“Effect of solar radiation pressure on Hayabusa’s position control”｜Space Science Institute
This “ Hayabusa position control The effect of solar radiation pressure on
Surprisingly, The measurement result of the strength of solar radiation actually received by Hayabusa was written. It is .
” The solar radiation pressure obtained from this tilt is
1.261×10-10[km/s**2]= 1.25 [m/s/day]=4.5 [ km/hour/day] and .
On an ideal reflecting surface, the solar radiation pressure exerts a force equivalent to the gravity acting on a one-yen coin per 1000 square meters. increase.
Actually the reflection is not perfect so the force will be weaker. “
I couldn’t figure out what kind of unit [km/hour/day] was.
It’s not simply acceleration, Pascal, Newton, or anything like that.
…Also, I found out during the investigation process that Hayabusa2 seems to be using a solar sail for attitude control.
On the next page, I will introduce the magnetic sail.
