RANDY L. PHELPS

This is the Space-Based Observatories Module

For this assignment, please look through the "lecture" notes for "Space-Based Observatories".  These notes contain the material, in condensed form, that I will expect you to become familiar with.  By that, for this assignment, I simply mean to become familiar with the observatories I outline in the notes (notice, there are few words!).  To become familiar with them, you will need to explore the links I have provided.  You will find that some of these links are somewhat technical, while some are good at catering to a general audience.  I am aware of that, but do your best.  You will need to look at these links to become familiar with the material!

The purpose of this exercise is simply to show where much of the data that gives rise to our understanding of the Universe originates. 

Upon completing this assignment, you should be comfortable with the following material:

  • The regions of the electromagnetic spectrum, and where (from the ground, within the atmosphere, in orbit) each type is observable.
  • The relative energies of each type of electromagnetic radiation and what type of astronomical events/phenomena give rise to them.

Upon completing this assignment, you should be able to answer these, and similar questions

Applications

If two black holes collide, they would produce the most energy of any astronomical event, according to theory.  The energy would be released in a relatively short burst.  In what part of electromagnetic spectrum would you expect to see this burst of radiation?

  • When material spirals around a black hole, in a so-called accretion disk, it collides and is heated to high temperatures (i.e., high energies) before falling into the black hole itself.  In what part of the electromagnetic spectrum might you look to "see" this very high temperature gas, before it disappears into a black hole?
  • The outer atmosphere of the Sun, called the "corona", has a temperature of a million degrees Kelvin.  In what part of the electromagnetic spectrum might you look to study this hot, high energy gas?
  • "Solar flares" are giant storms on the Sun that release huge amounts of energy.  When a "solar flare" occurs on the Sun, in part of the electromagnetic spectrum might you look to study the explosion?
  • Stars more massive than the Sun are hot, with temperatures of 10,000-20,000 Kelvin at their "surfaces".  The Sun, with a temperature of 6,000 Kelvin (at its "surface"), emits most of its light in the visible part of electromagentic spectrum.  In what part of the electromagnetic spectrum might you look to study hot stars?
  • Even though visible light reaches the Earth's surface, NASA has spent billions of dollars to operate the Hubble Space Telescope (HST) in orbit around the Earth.  Why?
  • When a star is forming, it has not yet reached a temperature like a normal star, but rather it is still relatively cool.  In what part of the electromagnetic spectrum might you look to see newly forming stars?
  • In cold, dense, gaseous clouds where stars form, molecules collide and change their rotation states.  It is within these so-called "Giant Molecular Clouds" that stars begin to form.  In what part of the electromagnetic spectrum might you look to study regions where stars might form?

 

These questions, and similar ones, will form the basis of  the exam material for this section of the course.  If you have problems with the material, please see me.   If you are unable to answer some of the questions, I will help you before the date specified on the syllabus, provided you show me the results of your inquiry into the material.

That is, you must provide me the answers you we able to obtain for all questions, including your attempts at problem questions, before I will help you with any of them!   

In other words, for me to provide you with help with the questions, you must show me that you have undertaken a good-faith-effort to find the answers yourself, in a timely manner.