What is the evidence that suggests planetary systems are common in the universe?
What will be an ideal response?
We know that stars form surrounded by disks of gas and dust, that there is enough material in these systems to form many planets, and that, theoretically, planet growth should be common in these disks. Observationally, we have detected Jupiter- (and even Saturn-) mass planets around nearby stars using the Doppler technique, and the Kepler mission has shown (via transits) that a majority of stars have planets.
You might also like to view...
A white dwarf is ________
A) an early stage of a neutron star B) a precursor to a black hole C) a brown dwarf that has exhausted its fuel for nuclear fusion D) what most stars become when they die
A general rule for estimating the distance in kilometers between an observer and a lightning bolt is to count the number of seconds between seeing the lightning and hearing it, and dividing by
A) 2. B) 3. C) 4. D) 5. E) none of the above
When you run along the hall from one classroom to another you're moving through
A) space. B) time. C) both of these D) none of these
The evening sunsets are reddish orange because the atmosphere
A. absorbs blue light. B. is more efficient at scattering blue light. C. contains small amounts of red dust that give the air its red color. D. absorbs the red light. E. is most efficient at scattering red light.