With which of the following observations could Tycho have ...

[futuristic]

With which of the following observations could Tycho have demonstrated that a comet must be a celestial phenomenon? (Note: you may want to review Ch. 2)
 
  A) from the comet causing a full solar eclipse across much of Europe
  B) measuring changes in its brightness over time
  C) parallax measurements from observing it from two locations on Earth

Question 2

Visiting comets and asteroids: In recent years, several space probes have been sent to comets and asteroids to physically interact with them.
 
  Briefly describe three of these missions, and compare how each allows astronomers to better study the composition of these objects.

[HandsomeMarc]

Answer to Question 1

C

Answer to Question 2

Stardust directly collected dust from a comet's tail and returned it to Earth, where the material can be studied in great detail in laboratories. Deep Impact, on the other hand, released material from deep inside a comet into space (using an impactor) where it could be examined via spectroscopy using Earth-based telescopes. The Rosetta mission will place a lander on the surface of a comet, where it can use instruments to directly study the material on the comet's surface.

[futuristic]

Wow, this really help

[fatboyy09]

Thanks for the timely response, appreciate it