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society

Why Space Matters

Sometimes people question the value of science, like whether it matters we now have confirmation of liquid water on Mars. I often question the value of celebrity gossip, so it’s not a sufficient answer to simply reply, ‘Because, science.’ What would a possible future benefit from knowing more about space and other planets look like?

To answer the celebrity issue, maybe if you learn about a celebrity’s allergies you could stop them from eating something they shouldn’t and going into anaphylactic shock. But good luck with that.

In the case of water on Mars, it helps with planning for future missions to Mars, but can also let us learn about the types of worlds that can exist. Down the long road of the future, we might be quicker to figure out a similar planet is similar if we know more about Mars, just like if you know a lot about one actor, you might extrapolate information about another.

But more than that, a lot of the science and engineering from studying space are in figuring out “how do we figure out X?” We have some scientific question and we can’t just scratch off a lottery ticket and see what the answer is. We have to feel our way to the answer through a lot of obstacles.

In the case of water on Mars, we could have just sent a giant bomb full of color-changing-when-wet tablets to mars and blown it up, dispersing them all over the planet. But that would have put a bunch of those chemicals all over the planet, potentially ruining future explorations, and it might still not have given us the real answer, depending on when and how the water flows.

Instead, they sent a vehicle with a decent number of tools and sensors, including cameras, to look around, feel around. That meant doing a lot of work, including designing and building the rovers, which includes how to power them, how to get them to Mars, and how to get them onto the surface. A lot of those issues being solved helps build the next one better, and it also tells us where we need better technology.

Okay, okay, a lot of boring science stuff. Who cares? People on earth have other stuff to worry about.

But if and when we find out a big rock is on a collision course with earth, you’ll probably care, right? They’ve hit us before, and sooner or later we will probably have to deal with the prospect of an impact coming our way. Space exploration is an insurance policy. The more we know about space and getting up there and working up there, the better our chances at dealing with something that could make us all have a really, really bad time.

Categories
science

Solar Messaging for Interstellar Discovery

The sun, our star, emits something on the order of 400 terawatts (trillion, trillion watts; 15 zeros) of radiation. Per second. It is the biggest thing we have going for us. It lets us see, keeps us warm, powers our plant life.

In examining the question, “is earth alone?” we might turn to the sun. Launched in 2009, the Kepler space telescope has been finding remote planets. It has definitely found over one hundred such planets, and has thousands more unconfirmed. It does this work by focusing on the stars. It looks for telltale changes in what the star looks like over time, looks for a dimming that is caused by an orbiting planet moving between the star and the telescope.

The planets are too distant to be seen (yet?) by our instruments. But the stars, putting out terawatts of energy per second, we can see the stars.

And if we wish to signal to other intelligent life, or if it wishes to signal to us, the stars may be the most obvious and best bet. Because where else are we going to pick up a transmitter that can output terawatts?

But the trouble is how to wire this massive, powerful transmitter. As small as we are, with as limited resources as we have, it seems improbable we can make much of an impact on the solar output in any meaningful way. And even if we could, what way would that be, that would produce a detectable difference that would be definitive proof of life to aliens across the galaxy?

More importantly, what should we look for in the stars we can see?

The SETI Institute has been looking for intelligent life out there. But they tend to look for the alien equivalent of terrestrial signals: microwaves, radio waves, laser beacons. But, as far as I know, they do not look at the stars themselves, for anomalous readings that might indicate some subtle tampering by a local intelligence.

In a few hundred years, maybe, we will have advanced our space program and asteroid catalog far enough that we might endeavor to shift some asteroids about. We might do this with minimal effort, using a chain reaction in which we nudge one or a few asteroids ever so slightly. In this effort, we might produce a distinctive pattern for aliens who happen to glimpse our star. Maybe one that gives some sort of prime-number-based sequence to the next generation of alien Kepler-esque telescopes.

We might look for the same sorts of patterns in the stars we examine with our next generations of planet-finders.

Or maybe there is some other property of the stars we will learn to manipulate more easily? That we might find alien stars exhibiting the same changes?

What secrets do you see looking up at the stars? What secrets do you fail to see?