Below is a star field and in this field is a Kuiper Belt Object. Use the right and left arrow keys to go forward/backwards one day in time, so that the only object that moves is the Kuiper Belt Object. When you click on it, its angular position and measured flux (brightness) will be displayed.
To select a different star field press 1, 2 or 3. That will change your view of the sky.
Make sure your browser window is fully displayed.