Archive for August 2009

Silly, but funny.

August 7, 2009

This was my first attempt.

Then I was surprised by a failure to converge!

But then I got it in one with my next attempt.

Mary found a nice one in an old favorite.

She thought lyrics might give good results, but not Penny Lane.

A base slander led to a three-part loop.

Some things just translate well!

We had a romance novel fail.

And this reminded me it’s time for bed.


Science vs Consumer Detectors: Thank you, Mary.

August 4, 2009

I have been trying to figure out recently why people don’t understand what IR detector data looks like, given that we have examples and studies and in a few cases specifications of what we’ll get from JWST, and examples and analysis of NICMOS, Spitzer and some Keck data.  My wife explained it to me, and then I looked at the numbers.  She’s right, and I wanted to publicly thank her.

We have some simulated data, a cutout of which is shown here, that gives you the general idea of what the data will look like if it’s pretty good.  Jay Anderson (STScI) did this simulation.

Simulated NIRCam Data with 1% bad pixels

Simulated NIRCam Data with 1% bad pixels

That picture is 1 percent bad pixels, which is pretty good.  For the roughly 4 megapixel NIRCam, you’d expect to get 40,000 bad pixels, before you add any cosmic rays.  That means one in every hundred pixels is a bad one.  It could be one in 50.  And still, that’s pretty good.