Space and Physics
PUBLISHED
The discovery of interstellar comet 3I/ATLAS last year provided insights into a never-before-seen object. It's different from the two known other interstellar interlopers that we have observed crossing the Solar System, much older and faster. Telescopes on and around Earth, as well as spacecraft in deep space and even rovers on Mars, looked at this object as it whizzed by during its perihelion and closest approach last year. What we would really need, though, is a mission ready to intercept it. Now, a team has put forward a proposal on how to catch up with the comet. It's just going to take a few decades.
The rest of this article is behind a paywall. Please sign in or subscribe to access the full content.The European Space Agency is serious about a mission ready and waiting in orbit to go after a comet. It even has a very matter-of-fact name: Comet Interceptor. It will be launched in late 2028 or early 2029, and it will be parked in space, ready to go after a pristine comet or suitable interstellar object detected nearby. Unfortunately, even if we had this mission ready, 3I/ATLAS would not have been suitable.
“The issues of a direct mission are centred largely on the celestial mechanics of the target in question and these are first the retrograde orientation of 3I/ATLAS’s orbit, second the high heliocentric speed at infinity of ∼ 60 km s−1 (otherwise known as the hyperbolic excess speed, V∞), and third the rather late initial detection, when 3I/ATLAS was already within the orbit of Jupiter,” the authors of the mission proposal write in their paper.
Despite the crucial difficulties in sending a mission to catch up with 3I/ATLAS, there are some reasonable motivations for studying the object up close. This comet is something we have never seen before, and it’s unlikely that another one like it will cross the Solar System again any time soon, despite the large number of interstellar objects predicted to travel through it.
“[3I/ATLAS] is probably more interesting than what we can imagine it to be because it's like a time capsule from a different era,” Colin Wilson, European Space Agency Project Scientist for ExoMars and Mars Express, told IFLScience in October. “That is super interesting, and I would love for us to be able to visit it, land on it, and take a sample and bring it back.”
The new proposal by researchers from the Initiative for Interstellar Studies sees a mission able to catch up with 3I/ATLAS by using a Solar Oberth maneuver. The Oberth maneuver is a famous celestial mechanics approach where a spacecraft is sent towards a massive object. As it begins to fall into its gravitational potential well, it turns its rockets on, achieving additional speed.
Simulations suggest that the best time for it to launch would be 2035. The craft would be sent to Jupiter, and it would use the gravity of the planet to lose speed and move towards the Sun. As it approached the Sun, the Oberth maneuver would come into play, launching the craft at a much higher speed than would be possible with chemical rockets alone.
The mission could then get to 3I/ATLAS by 2085, just a little bit faster than the comet at a distance of 109 billion kilometers (68 billion miles) from us. For now, the work focuses just on the feasibility of such a maneuver and not on all the other challenges actually putting together a mission that would have to face Jupiter, the Sun, and then extremely deep space – with all the requirements that these very different environments demand – entails.
The paper is available on the ArXiv.
[H/T: Universe Today]
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