Questions with the keyword 'orbit'

• Why do planets orbit in an ellipse with the Sun at one focus? Why not a circle? And as a circle is an ellipse with by doppler to Adam, SheilaCategory: Space Comments: (So far, one comment )
• What do you think would kill us if the sun “went out”: Lack of light, lack of heat or drifting out of orbit and by mattiosmmm to Adam, Geoff, Rob, Sheila, SuzieCategory: Space Comments: (No comments so far )