LMC X-3 is a binary system that is believed to contain a black ...

[abarnes]

LMC X-3 is a binary system that is believed to contain a black hole.
 
  a. True
  b. False
  Indicate whether the statement is true or false

Question 2

What are some new techniques and technologies that enable construction of optical telescopes with very large mirrors?
 
  What will be an ideal response?

[micaelaswann]

Answer to Question 1

True

Answer to Question 2

Constructing large-mirror optical telescopes with thin, or floppy, mirrors has made the process much more feasible. Thin mirrors are lightweight and so do not require massive support structures. Some large mirrors are cast in a rotating oven that causes the molten glass to flow to form a concave upper surface, so grinding and polishing the mirror is relatively fast. Mirrors can also be made of segments, which are economical because each segment can be made separately. For both floppy and segmented mirrors, active optics, computer-driven thrusters behind the mirrors, is used to control their optical shapes.