When I was a kid interstellar exploration was something that people talked about as if it were only a matter of time before we figured it out. Fifty years later and I think we’re all a lot older and wiser. Even completely automated space craft reaching the nearest stars has begun to look like an improbability anytime within the next millennium. The scope of the resources needed to get something from here to even Proxima Centauri is staggering. Of course, I’m talking about a total project time that only totals into decades of time. If we’re interested in a 40,000-year round-trip, we could start working on it right now. But something like that is so laughably useless that I’d be embarrassed to even admit considering it as one of the options. To make the trip in a time frame that makes it useful the ship would have to accelerate to and decelerate from some considerable fraction of the speed of light. Let’s postulate 30% as the fraction. With that capability the trip would take something like twenty-five years round-trip. Sure, that’s a long time but our civilization should have a long enough attention span to follow up on the project and mine the results when the probe returns (if it returns). But the scope of such a project is too titanic for our current technological stage. It’s too grand.
Let’s look at more manageable projects. What’s doable?
I don’t have much enthusiasm for Elon Musk’s manned trip to Mars. Four or five years in space is a lot of radiation for astronauts to absorb. I don’t see the sense in it. I prefer the robot exploration thing we’ve been doing with the Voyager and later probes. The recent flyby of Pluto was very impressive. But I think much more ambitious unmanned exploration of the solar system is warranted.
I think the best bang for the buck is finding out if Europa has life in its ocean. I can imagine a series of visits. The first should be an orbiter that sends down a probe to take reading. Once the presence of water oceans has been confirmed a lander can be sent to try and find life.
I realize this is a large order to fill. I don’t know exactly how thick the ice crust is over the ocean. It may be many miles. If that is the case a very creative solution may be needed. Possibly a nuclear powered “drill” might be an option. Of course, if all else fails we could set off a nuke. Then again if there really are “Europans” we might start an interplanetary war. So maybe some thought will have to be expended thinking about the best way to search for life there. But I see a series of missions to attempt to answer this question as one of the most meaningful and exciting challenges that currently exist for mankind.
Of course, I’ve been talking of the cuff. Doing a quick AI search I see that the exact thickness of the ice is estimated to be between 5 and 20 miles thick. NASA’s Europa Clipper mission, launching in October 2024 and arriving at Jupiter around 2030, will use radar to penetrate the ice and measure its depth more precisely. So, chances are I’ll be old and broken down before much of anything is known about this ocean.
But I still find the prospect exciting. Imagine if some kind of multicellular life exists in that ocean. I hesitate to even imagine intelligent life there but it’s not impossible. We might find that wherever there’s liquid water and organic molecules life tends to develop from spores that float around in outer space. Now wouldn’t that be something?