Time travel is both incredibly simple and very complex. The simple part is to merely look up. This is easiest at night when the sun isn’t out, but believe it or not, with proper planning (and precautions) you can sometimes see other planets and even stars and satellites during the day! Light coming from the moon shows us the surface of the moon as it was about 1.28 seconds ago. That’s how long it takes a photon from the sun to bounce off the moon and hit our eyes. So when we look at the moon, or anything else in the sky, we are peering into the past.
It’s also pretty easy to look deeper into the past. While there are lots of objects that you can with the naked eye, with a pair of binoculars you can see many, many more. They are also brighter and bigger in binoculars than they are with just your eye. Turn towards M31 (the Andromeda Galaxy), and you’re looking 2,500,000 years into the past. That’s how long it takes light from the stars of M31 to reach Earth.
Of course, a Astropotamus wants to be able to look very deep into the past and be able to photograph it, which requires something more complex than binoculars. It takes a Time Machine. Time Machines work like (and look like) telescopes, which operate by gathering, bending, and folding light so that light that travels a long way can be made brighter and bigger than just what the eye sees.
In general terms, a Time Machine gathers a lot of light and bends it so it focuses onto a small area. This makes the image at tha point very bright with lots of detail. Sort of like having a 10 megapixel camera instead of a 2 megapixel one. The Time Machine then bends the light again so that spreads this focused light out, making it bigger. This is similar to why a 10MP camera image can be zoomed in or blown up much more than a 2MP image can – there’s more information in the source, so you can magnify smaller portions of it more easily and still have it look good.
The end result is a lot of magnification and a (usually) bright image so that a camera can be put at the end and an image captured. With proper exposure, some practice, a little luck, and maybe some computer image processing, the camera can take long exposures that gather even very faint light that your eye can’t see. This lets the camera capture images from very far away or from very dim objects, which lets the Astropotamus share his time travels with the rest of the world by posting the images here!
In case you want to know about the Astropotamus’s Time Machine (also known as the telescope), here you go:
- Celestron 8″ Schmidt-Cassegrain f/11 OTA (Optical Tube Assembly)
- 2″ diagonal focuser (only used for looking with your eye)
- Some eyepieces (they magnify the image a little or a lot)
- Electric clock drive (for tracking objects)
- Equatorial wedge (for tilting the telescope at the right angle to let the clock drive work properly)
- Tripod (which keeps it all steady)
- Red dot star finder (to help in aiming the Time Machine at the right place in the sky)
- Piggy-back camera mount (this lets us mount a camera on the Time Machine)
- T-mount adapter, T-mount extension tubes, and T-mount thread for the DSLR (this lets us use the Time Machine directly as if it were the camera lens)
- Digital Single Lens Reflex (DSLR) camera (for capturing images)
- Lots of computer software (for image processing)
Lots of other things go into planning and doing the work as well, but now you know what the Astropotamus’s Time Machine is!