The best way to solve the mystery is to catch up with it, get close to it, observe it, and study it.
The Lyra light sail probe approaches interstellar visitors (imagine). i4is
In 2017, the mysterious interstellar visitor "Ou Momo" went to the solar system for a walk, then turned around and accelerated away.
"Oumuamua" has left too many mysteries for people. With the discovery already on its way back, the limited data leaves astronomers puzzled by its nature. Even today, 5 years after "Oumuamua" has left human vision, it is still inconclusive what "Oumuamua" is and where it comes from.
The best way to solve the mystery is to catch up with it, get close to it, observe it, study it. It's not easy. But already scientists have come up with ideas, including the so-called "Lyra Project."
Project Lyra aims to use advanced propulsion techniques, such as thermonuclear propulsion, especially light sail technology, to meet interstellar objects such as Oumuamua.
Less than two weeks after the discovery of "Oumuamua" in 2017, the "Initiative for Interstellar Studies" (i4is) proposed the so-called "Lyra Project" to study how to use existing or recently achievable technologies to conduct a close-up investigation of "Oumuamua".
The researchers said that most of the ideas for catching up with "Oumuamua" were based on the so-called "Solar Obers Maneuver".
The "Obers maneuver" is essentially a "gravitational slingshot" that has been widely used in deep space exploration. This technique typically uses the planet's gravitational pull as a "slingshot" to increase flight speed. The Solar Orbs Maneuver uses the Sun.
A "Solar Olbers Maneuver" can be divided into three steps. First, the probe is launched from Earth to a point furthest from the Sun, that is, the aphelion point in a preset orbit; then the probe falls back in the direction of the Sun; when the probe reaches the closest point to the Sun, that is, the perihelion, it is given additional thrust to make it reach a very fast flight speed.
The researchers say it's a fuel-saving, high-speed scheme that's ideal for catching up with interstellar visitors like Oumuamua who quickly navigate away after perihelion. But humans have never implemented the "solar gravitational slingshot" before.
Another question to consider in the plan is, how to resist the heat of the sun's fury at perihelion?
Unlike previous probes, probes flying to Oumuamua are not about how hot they are at a particular distance, but about how close they can get to the sun.
As the distance between the probe and the Sun gets closer, its thermal protection should become stronger and stronger. Until the limits of the design are reached.
The Parker Solar Probe, which crosses the corona, carries a heavy thermal shield. If we use thin and light sails to advance, then how to protect the probe chasing "Oumuamua" near the perihelion will be a very difficult problem.
To that end, the researchers envisioned alternatives, including the use of Jupiter for catapults.
The scheme of using Jupiter catapults is known as the "Jupiter Olbers Maneuver". After the probe lifts off from Earth, it will first skim over Venus, then again, and finally use Jupiter's gravity to make a final acceleration.
The advantage of the Jupiter Orbers Maneuver is that the probe does not need to be equipped with a heavy thermal shield, and the flight distance and time required are greatly shortened. The required technology is also readily available.
However, the flight speed of the probe will be slower and the duration of the mission will be longer.
But considering that once the probe approaches Oumuamua, the relative speed between the two becomes important — if the speed is too fast, there will be less time to detect; this disadvantage will turn into an advantage.
Probes that use the Sun to accelerate can fly at speeds of up to 30 kilometers per second, while probes that use Jupiter to accelerate can only fly at about 18 kilometers per second.
The researchers say that if we decide to catch up with "Oumuamua", then there will be a launch window in 2028. If a light-sail detector can take off in 2028, it can theoretically catch up with "Oumuamua" in 2054 in 26 years.
The array of light sail probes flies away from the solar system (image). Adrian Mann
reference
Project Lyra: A Mission to 1I/‘Oumuamua without Solar Oberth Manoeuvre
https://arxiv.org/abs/2201.04240