 Greetings and welcome to the Introduction to Astronomy. In today's Misconception in Astronomy, we are going to look at the idea that comets zip across the sky and see why this is actually incorrect. So what do we see when we see a comet? So when we see a comet in the sky, such as in our image here, and we see the comet off to the left, and you can see the head of the comet down to lower here and then the tail stretching back away. Now this, when you see this comet, it would not appear to flash across the sky. It would just kind of hang there in the sky and slowly move, rising or setting, with the rest of the stars. So the answer to our Misconception is definitely no, comets do not move quickly across the sky. This is often a confusion between a meteor and a shooting star or shooting star and a comet. So there's a difference between these two. Comets are very large icy bodies, many kilometers across, which move in orbits much like the planets do. Meteors, on the other hand, are tiny bits of material that are burning up in Earth's atmosphere. So a comet is not something associated with our atmosphere and is not moving quickly across the sky. In reality, we see when we look at a comet, we're looking at something much further away, comparable to the distance of a planet. Now that is not to say that comets do not move. They actually do, and we can take a look at an example here, and here are a number of images of this comet. And you can see how it did appear to move slowly among the constellations over the period of a short period here. So this is actually over the period of about two months, maybe two and a half months, and you can see how the comet did appear to move. And you can see how it started here, moved around, and here as it was getting closer and closer to the sun, then the tail would get more and more prominent. So they do wander among the stars and will change position. They can move as slow as a planet. If they're further away from Earth, they can move even faster when they happen to come very close. But they do not flash across the sky much as a shooting star does. There's a big difference between a comet and a shooting star. Now we can also get an idea of how they move. Here, let's take a look at this image. Here is an image looking at a comet, and we're looking, we're focused on the comet and are the tracking the comet position. And you note that all of the other stars appear to have moved. So when you follow the comet, the stars will appear to move over a short period of time. However, it is still not large enough, and you would not notice it over the course of a day very easily. You would have to very carefully track the position of this to see it change in position. So they do slowly move among the stars, much like the planets do, and they rise and set like all other objects in the sky. But they are not objects that flash across our sky. That would actually be a meteor or shooting star. So let's go ahead and summarize what we've looked at here and what we've talked about and found out is that comets do not flash across the sky. So they are not the same thing as a meteor or a shooting star. There is a big difference between a comet and these two types of objects. They do slowly move among the stars, much as the planets do. That's how planets originally got their name as wanderers that wandered among the stars. So that concludes this misconception in astronomy on comets flashing across the sky. We'll be back again next time for another misconception in astronomy. So until then, have a great day everyone, and I will see you in class.