 Greetings and welcome to the Introduction to Astronomy. In this lecture we are going to begin our discussion of the exploration of the Solar System, and I will start out with an introduction as to what this series will consist of over the next few months. So what I intend to do is consider how we have studied the sky. Certainly we've looked at the sky since ancient times, and we have really only had direct study and been able to directly explore objects in our solar system since the space age, since we've been able to put satellites out in space. So what I'm going to do with this series, and I intend to eventually get up to modern day, although that may take a little while because there's been a lot of craft that have explored different parts of our solar system. So over the next few months I will try to get a start on this and try to merge into at least the first decade or so from the late 1950s through the 1960s and talk about our early exploration of the solar system. So we'll start, for example, with the first satellite put into space, and that was the Sputnik satellite, a replica of which is pictured here, and we will look at many of the other craft over the course of this series that have explored the solar system. So we have had craft explore Mars, as shown here, and we'll see how our understanding of our solar system has changed by being able to directly explore and sample these other bodies. So when we get into even more modern we can look at things like exploration of asteroids and sample return from very small asteroids that could not be imaged like this from Earth. All we can see from Earth is a dot of light. So being able to travel out there and get close-up images but then to be able to get a sample to return to Earth really allows us much greater understanding of our solar system than we can possibly do just from Earth alone. So let's go ahead and summarize what we're doing for this introduction here. So I am going to discuss the different craft that have been used to explore our solar system. That can start with satellites put into space to observe Earth, and it can be objects that have continued out to study other objects in our solar system, whether they be planets, whether it be our sun, and whether it be some of the moons or asteroids or other objects within our solar system. And my intention eventually is to get up to the modern craft current, but that will be as time permits. This may be a few month series running through the spring semester, and then we may pause for a little bit to work on some other things as well. But the intention in the long run is to really go through many of the different crafts that have explored our solar system. So that concludes this introduction to our exploration of the solar system. We'll be back again next time to start our study of this. So until then, have a great day everyone, and I will see you in class.