What does the Oumuamua asteroid have to do with climate change?

Yes, there is a sort of connection.  OK, it’s not connecting the asteroid and climate change—but rather these two ideas help us understand the nature of science.

Oumuanua

I’m going to start with Oumuamua (which is fun to say out loud).  In case you aren’t familiar with it, this is the name of the recently discovered asteroid that appears to be from outside our solar system. It’s a pretty big deal.  Here’s what we know.

  • Oumuamua is from outside of our solar system and it’s not a comet (because it doesn’t have a coma).  Oh, we know it’s interstellar because of the direction it comes from as well as it’s speed (too fast to stay in the solar system).
  • The asteroid is long and skinny and rotating.  We know this based on the changing brightness as it rotates.

Now for the weird part.  If you just use the gravitational forces on the asteroid, it should move in a different path than it does.  So, why does it deviate from a purely gravitational trajectory?  We don’t know for sure.  One option is that there is a tiny force from the interaction with the sunlight that can push it.  In order for this to have a significant effect, the asteroid must either have super low density or be super thin.

Option B: the asteroid isn’t an asteroid but instead it’s an alien spaceship with thrusters.

OK, I didn’t get all the details perfect—but I think you get the idea.  It’s a weird asteroid and we don’t know everything about it.  Here, this video from Scott Manley gives a nice summary.

Oh, this article is pretty nice too (from The Verge).  But just to be clear—the motion of the asteroid COULD BE because it’s an alien.

Climate Change

I’m not going into all the details here (NASA does a nice job if you need more).  Let me just give the super simple version.

  • There is this thing called “The Sun”.  It’s in space and it radiates light in all directions.
  • Some of this light hits the surface of the Earth.
  • Some of the light that hits the Earth reflects, some gets absorbed and warms up the surface of the Earth.
  • When the surface of the Earth warms up, it radiates infrared light.
  • There is carbon dioxide in the atmosphere.  Carbon dioxide absorbs and re-radiates infrared.  This essentially makes the Earth warmer than it should be (this is good thing).  Oh, other gases do this too.
  • Humans add carbon dioxide to the atmosphere. Yes, by breathing—but we add a whole bunch more because we burn fossil fuels.  Oooops.  We added too much.

OK, that’s the short scoop.  Humans can measure the temperature of the Earth (not a trivial task) and they can measure the amount of carbon dioxide (this is a bit easier).  In the end, it seems very clear that humans add carbon dioxide and the carbon dioxide is warming the Earth and changing the climate.

Now for the Nature of Science

Science is the process of building models.  Science is NOT the process of finding The Truth.  In fact, we never know what’s absolutely true.  Here is my favorite example.

Take a ball.  Hold it out in front of you and then let go.  What will happen?  If you say “oh, it’s going to drop”—I agree.  That’s the most likely thing that will happen (since I’ve seen this like a million times).  But just because I’m very confident of the outcome doesn’t mean that it’s true.  The only way to find out if all balls fall when dropped is to drop ALL the balls ALL the times—like forever into the future.

OK, we can’t prove things are true but we can show when they are wrong.  If I have a science model that says all balls are red, I just need to find one ball that isn’t red and BOOM—I showed that was wrong.  This is just a fundamental nature of science.

Now let’s jump to publishing stuff in science.  Here, Katie Mack has a nice twitter thread on this.  Read the whole thing—it’s not long.

When scientists are writing about Oumuamua, they try to eliminate ideas.  They have collected evidence that the asteroid doesn’t move based just on the gravitational interaction, so they can eliminate that idea.

But what about aliens?  There’s not data that says it CAN’T be aliens.  Does that means it’s aliens?  Does that mean we think it’s aliens?  Does that mean that Will Smith and Jeff Goldblum need to steal an alien ship and fly into the mothership to upload a virus and save humankind?  No.

What about climate change?  Is it possible that there is something else going on other than human production of carbon dioxide?  Well, we haven’t disproven every possible idea.  Again, it’s possible that climate change is caused by aliens.  It’s possible, but unlikely—just like a released ball is just going to hover in the air when I let go of it.

When people (you know who you are) say something like this:

Oh, but only 97 percent of published papers in climate science say that humans cause climate change.  So, it could be fake.  We should burn more coal.  MORE COAL.

Well, how many published papers on Oumuamua include the possibility of aliens? Do we really think it’s aliens?

Someone needs to go through all the Oumuaua papers and calculate the percent of them that mentions aliens.

 

 

 

 

Hurricane models and the nature of science

Here I am, at my parents house. There is no power at my house and Louisiana in September with no power is really a whole bunch of no-fun. But maybe I can use this time to talk about science.

**The Nature of Science**

Here is a review. What is science all about? (I am pretty sure I talked about this before) Science is about making observations and from those observations creating models. If the model predicts other things that are confirmed, then that is good. If not, the model must be changed. Really, it’s that simple.

**Hurricane Models**

It is somewhat interesting that forecasting hurricanes is quite similar. To do this, they (hurricane people) start with a model of how a storm behaves. In this model they input the current weather conditions and run the model. Not everyone agrees on how a storm would behave given some initial conditions and not everyone agrees on what the initial conditions even are. The result is that there are several models (as shown below):
![hurricane models](http://blog.dotphys.net/wp-content/uploads/2008/09/hurricane-models.jpg)
(from [Weather Underground – a great weather site](http://www.wunderground.com))
Notice that the models do not agree. Everyone knows the models are not perfect, so multiple models are good. If the models are close in agreement, then there is more certainty in the track.

On a somewhat related note, I remember for a previous hurricane a weatherman said the following:
>The models say the hurricane will hit HERE. So, it’s NOT going to do that. It will either hit to the left or the right because the model is never correct.

I still find that quote to be quite funny. This would be the same as a person with a gun that is a bad shot. It is ok to aim at someone because the WILL miss.