Testing the observatory I decided to try a very faint asteroide.
Chosed the 2015 ON73 wandering around in the Triangulum near the Andromeda border with a magnitude close to 20.
Decided on 180s exposures through a Luminance filter (Clear), the setup used was a 30cm aperture SCT and the CCD a KAF3200ME from the SBIG ST-10XME.
The mount guided very well and made a sequence of 16 exposures in order to stack them to see if the target showed up.
…Well it showed up in a single exposure.
To see it properly and in order to get it's position I used Astrometrica. The program finds the direction of the asteroid movement and it's speed and stacks the images on top of the asteroid position adding each image flux to get a better signal to noise ratio. In this case the asteroid movement freezes and the stars trail.
Using the Astrometrica tool to determine the manitude and position difference to the orbital prediction, we find the 2015 ON73 was spot ON by the predicted position.
For eur25 you get a nice tool to play http://www.astrometrica.at/
Blink of two images showing the asteroid in two different positions.
Sum of all images to show the trail of the asteroid movement in the sky.
Joao Gregorio