Lecture16 - Lecture#16 Venus Earth's sister planet General...

Info icon This preview shows pages 1–3. Sign up to view the full content.

1 Astro 102/104 1 Lecture #16: • Venus: Earth’s sister planet. General properties. Telescopic observations. Space missions. Interior, surface, atmosphere. • Readings: Chapters 7.1(Venus), 9.5, 10.5 Astro 102/104 2 The Main Point Venus is very much like the Earth in terms of its size, density and presumably interior structure. However its surface and atmosphere are very different from Earth’s. Astro 102/104 3 Basic Properties of Venus Average Distance from Sun: 108,200,000 km (0.72 AU). Orbital period: 225 days. Period of Spin around axis: -243 days! Venus is spinning extremely slowly. And...it's spinning backwards relative to most everything else... Mass: 4.9x10 24 kg = 0.81 M E ; Radius: 6052 km = 0.95 R E . Density = 5.3 g/cm 3 (recall that Earth ~5.5 g/cm 3 ). Surface Gravity = 8.9 m/sec 2 (91% of Earth's). Thick CO 2 -rich atmosphere; Surface pressure ~90x Earth's. Average Surface Temperature: +482°C (900°F!) Complex surface geologic processes at work... Astro 102/104 4 Observations Venus is a prominent morning or evening "star", always within ~50° of the Sun. • Venus goes through phases like the Moon, visible in even small telescopes. • Venus is so bright partly because it is so close, but also because we are seeing sunlight reflected off bright cloudtops!
Image of page 1

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

2 Astro 102/104 5 Venus Transit on June 8, 2004 Next transit on June 6, 2012.
Image of page 2
Image of page 3
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