{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Our Place - Our Place In space Earth 1 planet of 8 Sun an...

Info icon This preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Our Place In space… Earth – 1 planet of 8 Sun – an ordinary star. One of 100 billion in our galaxy the “Milky way” Milky Way – typical galaxy, one of 10s or 100s of billions of galaxy in observable universe The scale of thins Solar system :all 8 planets lie within about 40 astronomical units. 1 AU is about 150 million km Distance between stars often measured in light years Speed of light = 300,000 km/s = 9.46 trillion km/yr 1 light year = 9.46 trillion km (5.88 trillion miles) Our galaxy is about 100.00 ly across How can we know what the universe was like in the past? Light travels at a finite speed Moon light travel time 1 second Sun light travel time 8 minutes Sirius light travel time 8 years Andromeda Galaxy light travel time 2.5 million years Thus we see objects as they were in the past. The farther away we look in distance the further back we look in time. How is Earth moving in our solar system Contrary to our perception we are not sitting still.
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern