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rodgrac
2012-Feb-02, 08:14 AM
I'm a payload subsystem member of a student satellite team.Infrared imaging is our main payload. I'm are trying to find a good application of the image data we receive.It is a nano-satellite with a weight of roughly 3 kgs.The altitude of the orbit is roughly 800 Kms. Ocean imaging using an IR camera is what I was thinking of. It would be helpful if I would get some more applications with an IR imaging camera. I doubt that when we focus the camera on the ocean surface by increasing the focal length as mentioned, the clouds will interfere in the image. Can this happen?

Hornblower
2012-Feb-02, 01:19 PM
I'm a payload subsystem member of a student satellite team.Infrared imaging is our main payload. I'm are trying to find a good application of the image data we receive.It is a nano-satellite with a weight of roughly 3 kgs.The altitude of the orbit is roughly 800 Kms. Ocean imaging using an IR camera is what I was thinking of. It would be helpful if I would get some more applications with an IR imaging camera. I doubt that when we focus the camera on the ocean surface by increasing the focal length as mentioned, the clouds will interfere in the image. Can this happen?

For starters, perhaps you could monitor the movements of warm water in the Pacific Ocean during the El Nino/La Nina cycle.

Shaula
2012-Feb-02, 04:50 PM
For starters what waveband IR? What are the rough specs on the camera?

Have a look at the MODIS specs site here (http://modis.gsfc.nasa.gov/about/specifications.php) - that breaks down the use of MODIS data by band.

Essentially if you are using a camera with a high NESR then that is going to hit what you can do quite hard. Also you need to consider that if you are going to try to monitor anything the orbit is very important. I am guessing that the camera is not going to be temperature stabilised? Direct sunlight could have a big effect on it if that is the case. All depends how it is mounted.

Let me know what the waveband is and I dig up some examples of what you can do with it.

rodgrac
2012-Feb-03, 08:15 AM
Hi!
Camera specs.:
Waveband:7.5-13.5 micro meter
Field of view: 45 37
Sensitivity(NEdT): <50 mK at f/1.0
Focal length:13mm.
The cameras' focus will be on the ocean surface.

What does NESR stand for?
What applications are possible?

rodgrac
2012-Feb-03, 02:17 PM
Hi!
These are some of the specifications of the camera:
Band width:7.5-13.5 micrometers.
Field of view:45 37
Focal length:13mm
Sensitivity(NEdT):<50 mK at f/1.0
And a small doubt:If IR can pass through clouds while monitoring ocean surface then how can we monitor the clouds temperature? Does that have something to do with the focus of the camera?

Shaula
2012-Feb-03, 04:39 PM
OK so you are looking at a broadband LWIR camera. NESR is a generalised form of the stat you have given as NEdT, just a measure of the noise floor. Most of the applications are going to be thermal. Which means things like cloud top temperatures, ocean currents (as Hornblower has said), surface temperatures.

Some ideas for projects (not sure if you will have the resolution/pointing accuracy for them all):
1) Urban heat islands. Look for temperature differences between rural and urban areas. Measure the effect of solar forcing on this effect.
2) Cloud heights. Estimate their relative temperatures, use this to estimate their height based on local atmospheric conditions (may need to link up with a meteorology department to do this)
3) Looking at ocean currents - tracking warm/cold surface waters
4) Volcanoes - if you get a lucky shot of one that is not quite dormant can you spot any activity?
5) Bush fires - if there are any going on can you map their extent?
6) Snow cover - snow has a higher emissivity than rock so should be brighter at a given temperature.
7) Vegetation analysis. Healthy vegetation has a higher emissivity than dead/dying vegetation. (Better in the 3-5 region but still worth a shot)

Hope that gets you thinking!

rodgrac
2012-Feb-08, 05:26 PM
Hi,
I am pleased to say that your information helped a lot in fixing the payload.
We have finally decided on four applications using the IR camera:
1.Cloud monitoring
2.Ocean surface imaging
3.Observe urban heat islands.
4.Snow cover and polar caps monitoring(depends on orbit inclination)
We had decided on the QUARK model IR camera manufactured by FLIR company.Most of the features look good.But, the range of detection is very less.Actually, the camera would be clicking the image from roughly 800 Kms. Here is the link leading to the datasheet of this camera:
http://www.flir.com/cvs/cores/view/?id=51266&collectionid=549&col=51276
Can you kindly go briefly through the features and conclude whether it could be implemented for the above applications in the satellite.(especially the range of detection looks bad).
It would be great if you would mention some companies better than this in IR space imaging.Because this company doesn't manufacture space graded cameras.
Awaiting for your reply,
Thank you.