Recent Discoveries

Question 1

Discussion Topic for Session 5: Post an article that is about Searching for Extrasolar Planets. This can be about any of the many recent discoveries of planets orbiting other stars.

General Information about Discussions: The purpose of the discussions is to keep up to date with recent discoveries and also to engage you in rich, scientific discussion. Each session you are asked to post an article from the Internet and to lead a discussion about the content of the article with a group of your classmates. Discussions are an important part of the course and thus are worth 33% of your grade. They are live during each session and can not be made up later.

For each session you should:

1. Post a scientifically-valid article on the session’s topic with its URL and a 1-3 paragraph summary of the article for your groupmates. You must post a unique article that no one has posted yet in the group.

Question 2

The Hydrogen alpha spectral line has a rest wavelength of 656 nm. If hydrogen alpha absorption from an object has an observed wavelength of 657 nm, what is the velocity of the object relative to us, and in which direction? Predict the wavelength at which we should observe Hydrogen beta absorption, which has a rest wavelength of 486 nm.

Question 3

please answer in a minimum of five sentences each 🙂

q1: Do you agree or disagree with the theories about the Permian-Triassic extinction? Use facts from this unit to support your opinion.

q2: If an asteroid were going to impact Earth, would you prefer to know in advance or let the NEO remain a mystery until impact? Why?