 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.apod. And today's picture, for August 21st of 2023, well it is titled Introducing Comet Nishimura. So what do we see here? Well, here is a comet and in fact a recently discovered one just about a week and a half ago that it was first discovered and imaged. And the question will be whether it will end up being visible to the naked eye. Is it a comet we will be able to see in the sky? And that is certainly a possibility based on how it is brightening. But it's very difficult to tell. It's not something that we can easily say will be bright enough because comets are very unpredictable. Sometimes they seem to brighten very quickly at first and then slow down and do not brighten further. So it's not something we can tell but it is something to look at over the next month or so as a chance to be able to see a naked eye comet. One of the other things that it will be doing is that it's going to be relatively close to the sun. Now, not just in distance but also in its angular distance meaning that it will never be very far away from the sun which will make it harder to see. It could be visible right before sunrise or right after sunset but not in the darker part of night which would make it even more easily visible. So it is something again that we can look at here and we see the comet itself in this image with the green coma around the nucleus which of course the nucleus is invisible being much too small to see at this scale and then we can see a tail stretching back toward the right hand side. Now as it gets closer to the sun the tail can develop and become even more prominent. So again, something else that we'll want to watch for to see how this comet behaves as it comes closer to the sun. When the comet comes close to the sun it's all of the material being vaporized off of its surface and then pushed back by the solar wind that gives us the greenish glow we see around for the head of the comet and then the tail stretching back outward. Now the comet seen here as I said discovered about ten days ago and that was discovered by Hideo Nishimura and it is, the comets are named after their discoverer. So anyone who discovers a new comet it would find that it would be named after them and that's how the comet gets its name. So we use that, it will see that many comets some comets are named after now telescopes and automated surveys that are searching the sky they pick up a lot of the comets but still here we have even now some of them are discovered by people photographing the sky. So just by taking photographs of the sky and able to determine this new comet as it gets mapped out and we determine its orbit one can get the comet ended up being named after them. So that was our picture of the day for August 21st of 2023 it was titled Introducing Comet Nishimura we'll be back again tomorrow for the next picture previewed to be Nebula Unknown so we'll see what that is about tomorrow and until then have a great day everyone and I will see you in class.