141. What was the first spacecraft to orbit another planet?
142. The average density of comets known is:
143. What is the source of energy in a supernova explosion?
144. Which is the nearest point to the Sun in the orbit of a planet / space object?
145. Recognize the image.
146. ROSAT was a:
147. A star that forms by contraction of the gas from a giant molecular cloud is called:
T Tauri star
148. By which fusion reaction, the stars convert hydrogen to helium?
Carbon - Nitrogen - Oxygen Cycle
Carbon - Nitrogen - Nitrogen Cycle
Deuterium - tritium
149. Who was the first man to classify stars according to their brightness?
150. What is the diameter of the star UY Scuti?
2.4 billion km
1.1 billion km
3.2 billion km
1.9 billion km