How were the earth, sun and moon formed?
What is the term for the amount of energy released from each square meter of an objects surface each second?
What is the speed of solar wind?
When did solar system come into existence? What is the expected life of solar system?
How long is a day on saturn?
The 29 days it takes the moon to complete an orbit around the earth is called a?
The work of this harvard college observatory scientist made possible the first accurate determination of extragalactic distances by what is often called henriettas law?
What are the scientific names for the two regions of a sunspot?
What are black holes? Do they exist in reality?
Tell me how many moons do mars have?
Which of the pulsating variable star whose brightness varies in a very regular time period of about 1-50 days?
Why these stars are called novae?
How many stars are there, which are normally visible?
Which is the brighest star?
Tell me how many planets are now in the solar system?