Sh2-240 with more photons.

The Sh2-240 (Simeis 147) is a very faint supernova remaint in Taurus.

The image is in false color to show hydrogen alpha emission.

Original BW H-alpha image at the bottom

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This is a huge object, it covers nearly 3 degrees (6 full moons) on the sky.

Estimated distance from my home town Oulu is about

3000 light-years. The width of the object is 160 light-years.

This supernova remnant has an apparent age of about 100.000 years.

(Light from massive explosion reached Earth 100.000 years ago)

In the center of the remaint, there is a fast spinning neutron star or pulsar.

I started this project with, Sh2-240 supernova remant, at march 6. 2008.

So far I have collected lights for this very dim object litle by litle.

I feel like there have been all possible troubles with this object.

Number one, weather... like to say word or two but I hold back.

Number two, mechanical problems with guiding and only with this object!

Number three, bad flats, there is something seriously wrong with my flat frame box.

(I'll make a new one by using EL-panel!)

And many more troubles, only about one of three light frames was usable

doe the thin upper clouds.

They are allmoust impossible to spot from my location. Normally so thin clouds does not do too much harm. In this case the target has so low surfage brightness, that even slight

variations in transparency distroy the image.

The effect of bad trancparency is possible to spot during processing, so lots of work for nothing has been done here.

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IMAGING DETAILS
Optics:

Canon FD 200mm f2.8 lens with full aperature

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Camera:

QHY8

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Platform and guiding:

LX200 GPS 12" with QHY5 guider and PHD-guiding

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Exposures:

10 x 3600s + 4 x 2700s + 3 x 900s H-alpha + Flats and Bias frames, no darks

exposure time so far 13h 45min.

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Filter:

Baader 7nm H-alp + IDAS LP for RGB

Hydroge alpha channel only

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Update:

I reprocessed images, and I was able to go litle deeper, I think.

The data is yet "thin" and more exposures are needed, maybe an other ten hours.