Even the closest asteroids are so far away that they look like "dots" in the night sky - just like stars! So, you might think it is very hard to spot them, even with a big telescope.
But unlike stars, asteroids are part of our Solar System and orbit the Sun. This means that, when observing over a relatively small amount of time, asteroids seem to move quickly across the sky while stars do not.
In the Go Observing programme you'll use for this project, the telescope follows the NEO across the sky and takes 6 images at different intervals. The first 3 images (numbered 000, 001, and 002 at the end) are taken 1 to 2 minutes apart. These form a short-interval data set. The last 3 images (numbered 003, 004, and 005 at the end) are taken approximately 20 minutes later. These form a long-interval data set, with bigger time gaps between images e.g. 15, 20, or 40 minutes apart.
Because the telescope is tracking the asteroid across the sky, the background appears to move whilst the asteroid stays mostly fixed in place. This can give the illusion that the asteroid is "moving" opposite to everything else in the image.
You can see this in the video below. 3 observations of the asteroid 1916 Boreas are shown one after the other (we call this "blinking" the images).
The asteroid resembles the stars around it, but doesn't move towards the lower left between images like they do. You might also spot some tiny white pixels that remain static as well. These are "hot" pixels in the camera sensor. Be careful not to confuse these for the asteroid!
If an asteroid is traveling fast enough, it should be noticeable in the short-interval data set. But a slower asteroid may be harder to spot over a short-interval because it's not moving much. This is why a long-interval data set is obtained as well.
The video below shows the long-interval images for asteroid 1916 Boreas. Though the asteroid could be seen in the short-interval data set, it's easier to find in these images.
And that's all there is to it. Use the image software to open up the images in order, "blink" them, and whichever object is not moving like the others is the asteroid!
But before you request any observations of NEOs, we recommend practicing with some example data of asteroid 138205 (2000 EZ148). Use the instructions on the next webpage and see if you can spot the asteroid!