Tag Archives: NEO

Analysing CCD characteristics and Determining minimum optimal exposure time.

Motivation

My main interest st the moment is in minor planet astrometry, particularly of brighter Near Earth Asteroids. In order to get precise astrometry of these objects it helps if they are not moving in a single frame. Slow NEO’s can have rates of several arcseconds per minute so being able to take short exposures and stacking them is often required to get precise enough astrometry. It is possible to compute the minimum exposure needed for an asteroid by ensuring it’s movement does not exceed the FWHM of stars in your image, e.g. if an NEO is travelling at 4”/minute and you have a FWHM of 4” then an image one minute in duration will not show trailing. However it is also necessary to understand what the minimum exposure you can take with your setup is to minimise noise and maximise the signal to noise ratio. And it was necessary to understand the camera characteristics in order to make that determination. Continue reading Analysing CCD characteristics and Determining minimum optimal exposure time.

Z72’s first contribution to science

On Christmas Eve the Catalina sky survey spotted an object that had not been seen before. Shortly after McDonald observatory in Texas confirmed the object and further observations were needed to help nail down it’s orbit.

We had clear skies on Christmas night so I checked the Minor Planet Center NEO page to see if there were any possible targets and sure enough the object, provisionally called UY31A3B, was within the range of my equipment. Continue reading Z72’s first contribution to science