Remote Sensing C

[bernard]

[cryo]

Does anyone know what to expect from RemSen tests this year? I try to learn conceptually and have a great background in Earth science, so I'm hoping to do well, but I'm afraid my weakness will just be memorization of terms, satellites, etc. The rules seem to be ideally geared towards more conceptual questions, which I'm glad to see, but I'm afraid those will be difficult to write and test writers will just focus on the memorization aspect of this event. I can't seem to find many tests from 2017/2018 so I'm basically going in blind.

[cryo]

Does anyone know what to expect from RemSen tests this year? I try to learn conceptually and have a great background in Earth science, so I'm hoping to do well, but I'm afraid my weakness will just be memorization of terms, satellites, etc. The rules seem to be ideally geared towards more conceptual questions, which I'm glad to see, but I'm afraid those will be difficult to write and test writers will just focus on the memorization aspect of this event. I can't seem to find many tests from 2017/2018 so I'm basically going in blind.

Hello! I've never competed in this event, but I'm co-writing the Remote Sensing test for SOUP (Science Olympiad at the University of Pennsylvania), and while I obviously can't give any specific details about the test, I try in general for all tests to make them more conceptual-based rather than memorizing specific satellites, as I think it's a much fairer test of competitors' knowledge (although vocab definition questions definitely have their place for assessing basic knowledge). For new events or events that haven't been in competition for a few years though, it's important to keep in mind that we're all learning together though (even the event supervisors)! Look at the site's test exchange for example tests though! There's quite a number from 2017/2018.

[corila]

Hey y'all. Does anyone have any helpful tips for this event? Tbh, Earth science is not my strong suit so any tips on where to start would be helpful. Thanks

[oklumberjack34]

Howdy y'all,
I'm really new to this whole science olympiad thing, and very new to remote sensing. I was smoothing over notes and saw Planck's Function. I looked the equation up and it's a bull to say the least. Should I try and fit this on our notes sheet? Do y'all think it'd be on the test?
Thanks,
JB

[RiverWalker88]

Howdy y'all,
I'm really new to this whole science olympiad thing, and very new to remote sensing. I was smoothing over notes and saw Planck's Function. I looked the equation up and it's a bull to say the least. Should I try and fit this on our notes sheet? Do y'all think it'd be on the test?
Thanks,
JB

I've seen it pop up in a competition before, so it probably isn't a bad idea to put it on. As with most equations as well, you might want to spend a few minutes practicing using it, so that you know what context it is used in and won't stumble with a little operation error in the event (speaking from plenty of experience there...). It looks horrendous (and is, to be fair), but shouldn't be too difficult to apply.

I would link you to an example of it being used, but I can't find any. So here's one I made up, in case you are interested:

A satellite in orbit has a temperature of 280 Kelvin. It observes at around 21 microns. How intense is the thermal emission from this satellite at this band? (Could someone correct me if I messed up my wording of the question? Or my solving of the question?)

To make sure the units work out right, I'm going to first convert microns to meters (1 micron = 1 micrometer = 10^-6 m). So, 21 microns = 2.1*10^-5 m. The value for the Boltzmann constant is in J/K units, so I don't need to convert temperature from Kelvins.

We have a temperature and wavelength... so we can just plug into the Planck function.



Value of constants:
c = 3.00e8 m/s
k_B = 1.381e-23 J/K
h = 6.62e-34 J*s

So, plugging everything in, we get this horrible looking thing:


And the final trick is to put this into a calculator correctly. This is where I, personally, am most likely to make a mistake.

Here's what my screenshot from calculating the solution using desmos looks like. I am realizing that I might want to get pretty familiar pretty quickly with entering this into a scientific calculator...

PlanckExampleDesmos.jpg

So, the solution is 2768449 J s^-1 m^-3 (this seems pretty high, but some online solvers agree with me, so... maybe I just underestimated how much energy gets released as heat).

Also, I would recommend including units when solving your problem to make sure they work out. I calculated mine seperately so that I could determine the unit of the final answer, but this is generally bad practice. Here is how they work out (all of the units in the e^(crazy stuff) in the denominator of the second fraction cancel if you have everything in the units I have here).



If you are asked for anything other than the units shown (or W/m^3, which is equivalent), you'll have to do some conversions on the answer. So, for example, if you needed the answer in J s^-1 cm^-2 micron^-1 (I saw this unit, so I figured I'd give an example conversion, you would do):



This is probably way more of an answer than you bargained for, but hopefully it is useful to you or someone else?

The other thing I've seen is plugging variables and expressions into the Planck function, but that is much easier.

EDIT: I was bound to do something like write cm^1 instead of cm^2, wasn't I...