 Greetings and welcome to the Introduction to Astronomy! One of the things that I like to do in each of my introductory astronomy classes is to begin the class with the astronomy picture of the day. From the NASA website that is apod.nasa.gov slash apod. And today's picture for July 24th of 2023, while it is titled Chemicals Glow as a Meteor Disintegrates. So what do we see here? Well here we see an example of a meteor or shooting star and you may have seen these from time to time as they streak across the sky. Now meteors come in showers often and we have the Perseid meteor shower coming up in a few weeks here. That's usually the second week in August so that will be coming up shortly in which you'll be able to see a number of meteors if you're able to watch for a good amount of time. Their meteor showers are not thousands of meteors coming at a time but are a relatively small amount of meteors and you can still see on a good meteor shower even one or two a minute and maybe one every few minutes or longer for a less prominent meteor shower. Now here we see a very colorful meteor and the colors are caused by the material that made it up. Now meteors are just small bits of material in space. They can be little bits of ice. They can be little bits of rock. They can be any tiny bit of material that is around in space and when Earth's orbit happens to intersect their orbit they can crash into Earth and they vaporize in the atmosphere and that's what we're seeing is the trail left behind as that happens. Now normally their material left over from a comet so a lot of them are very icy material. There's some bits of rock as well but normally they burn up very high up in Earth's atmosphere and never reach the ground. However we can see the different colors and it does apply to the chemical elements that make them up. So the violet purple colors that we see here are generally associated with magnesium and calcium. The green can be a glow of nickel and the red is actually from this atmosphere not from itself but is nitrogen and oxygen that are energized by the meteor striking the atmosphere. So some of that is part of the meteor itself and others are parts of Earth's atmosphere which is still associated with the meteor in that they have been energized by it. So here we get to see this and again meteor is a matter of chance. You have to have your camera pointed in the right spot taking the image and just happen to have the meteor passing through. Well you can predict when there will likely be more meteors by the time you see a shooting star you'll never be able to set a camera up to get that picture because it will have long disappeared before you're able to get the camera set. So in many cases it's just you take lots and lots of pictures hoping to get a beautiful one showing all the different colors such as the one we're seeing today. So that was our picture of the day for July 4th of 2023. It was titled chemicals glow as a meteor disintegrates. We'll be back again tomorrow for the next picture. So until then have a great day everyone and I will see you in class.