Space shuttle Discovery is about 3 hours away from their de-orbit burn for an expected landing of (17:39 UTC).

NASA are about to start their go/no-go poll to close the payload bay doors.
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When attempting to get machines to process images you sometimes run into noise problems. Filters are regularly applied first to clean them up.

Editing the contrast of an image changes its dynamic range. In its most basic form, it will move pixel values away from the center (normally 128 if using 8 bits per color).

There are many different ways to to perform contrast adjustment.
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I’ve been getting around 200 spam comments a day on this site and had to manually sort through them to find the non spam comments. This morning I was finally fed up with comment spam on this site and decided to do something about it.
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I’m in the process of writing some code to detect the stars in astromical images. One of the filters I need to apply to an image is to convert it to greyscale.

Conversion to greyscale is relatively straightforward – The red, green and blue values of a pixel all need to be set to the same value.

There is one caveat, and that is that our eyes are sensitive to different colors. This means that color images tend to have lots of blue and red when compared to green.
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While the shuttle is on it’s way to the station, more debris is inbound.

NASA are deciding what to do. They may boost the station up a bit which will mean that the shuttle will get there a day later.

This piece of debris is to pass far closer than last week. Only half a mile this time.

I’m trying to find out exactly which piece is involved and will update this once more information is available.

This post is part of a series on understanding the meaning behind the values contained in a Two Line Element set, or Keplerian Elements. The main article is here.

First Time Derivative of the Mean Motion

Engineers like to use long confusing names for some of these fields. This field is sometimes called the “Ballistic Coefficient”.
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This post is part of a series on understanding the meaning behind the values contained in a Two Line Element set, or Keplerian Elements. The main article is here.

Epoch Year and Day

The epoch is simply the point in time that the two line element set is valid for.
The position of the satellite is supplied as part of the two line element set – The position for a particular point in time can then be calculated from the difference between the Epoch and the time you want to know.
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Space Shuttle discovery is still on track for a launch at 11:43pm UTC. Weather is perfect and everything looks good.

There is a sleeping bat attached to the external fuel tank however “The bat is not expected to interfere with launch this evening.”.

A live video feed is available here..

After fixing a problem with leaking fuel, Space Shuttle Discovery is still go for Launch on Sunday the 15th March.

Launch time is expected to be 23:43 UTC (Which is 19:43 EDT, or 12:43 Monday NZDT).

More information is available from http://www.nasa.gov/mission_pages/shuttle/main/.

Live video is available from http://www.nasa.gov/multimedia/nasatv/

This post is part of a series on understanding the meaning behind the values contained in a Two Line Element set, or Keplerian Elements. The main article is here.

Calculation of the Julian Day Number (JDN)

Julian day numbers are regularly used in astronomy instead of a date.

Julian day numbers are simply the count of days that have elapse since noon on January 1, 4713 BC Greenwich time using the Julian proleptic calendar.
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