There is an entire internet’s worth of information out there if you know where to look. There’s actually no excuse for not knowing stuff now if you have a device and a connection. Look at Friday evening for example.
There, up in the Eastern sky (near the top) was Jupiter. I knew this because I’d wondered what the shining star in the East was over the weekend, and I’d looked it up, before looking up at it.
As a bit of a demo, we got the tripod out, aimed and shot, hoping to get the four Galilean moons in the picture. It’s a quick and dirty image: I suppose I could have Googled for the best settings for this sort of thing, but as I say, this was a quick post-braai thing, and – much as I knew that the moons might be there – I picked the settings from my experience, rather than finding a site on the net.
Here’s what we got:
It’s not going to win any awards, other than maybe the one for demonstrating the four Galilean Moons of Jupiter to a few kids (and a couple of adults) after an early evening braai.
If I had tried harder or had more time, I could have done better, but that’s really not this was about. This was “That one there is Jupiter. Let’s see if we can see its moons and then get back to standing around the fire before I fall asleep.”
But then come the questions: How far away is that? How long will the light take to reach us? Which moon is which?
I can do a medium-rare rump over the coals and I can manage some functional camera settings, but I had to turn to the internet for these answers.
Currently, (current to when this was taken) Jupiter was 627.85 million kilometres away. That’s over four times the distance to the sun. I did a rudimentary calculation and that means that with light traveling (as it does) at 300000km per second, the light from Jupiter takes 35 minutes to get to us.
We’re essentially looking at a snapshot of Jupiter as it was just over half an hour ago.
But which moon is Io, or Europa, Ganymede or Callisto?
Well, surely there isn’t a site that can tell you that for any given moment?
All I had to do was to pop in the date and time that the image was taken, allow for our longitude, and make sure they knew I was using an Erect System (stop it).
So, from the top down on our photo are: Callisto, Europa, Io, Jupiter and Ganymede. All taken from a well-lit suburban back garden, with a basic camera and lens, and all informed by the internet.
It’s not just there for being shouted at by anti-vaxxers.
Some of it is quite useful.