Showing the number and relative size, velocity and distribution of the various types of celestial objects. ================+====================+=====================+===========+===================== | | |Velocities | Object | Number | Diameter | miles | Distribution | | | per sec. | ----------------+--------------------+---------------------+-----------+--------------------- 1. Solar System | | | | | | | | a. Planets |Eight |3,000 to 88,000 mi. |3 to 35 |Revolving in nearly | | | miles | circular orbits | | | per sec. | about the sun. b. Sun | |864,000 mi. |12-1/2 mi. |Travelling through | | | | galactic systems of 2. Stars | | | | stars (Milky Way). | | | | a. Helium | | |8 mi. | (bluish) | | | | b. Hydrogen |Approx. | Dwarfs |14 mi. |All types of stars are (white) | 2,000,000,000 (Two | 500,000 to | | more or less crowded c. Solar | thousand million) | 1,000,000 mi. |18-19 mi. | toward plane of Milky (yellow) | | | | Way in lens shaped d. Type M |Including all types | Giants |21 mi. | formation. (Milky (red) | | 10,000,000 to | | Way possibly a spiral | | 400,000,000 mi. | | nebula.) 3. Nebulæ | | | | | | | | a. Diffuse or |Numerous |Very extensive, many |Very low |In or close to Milky Gaseous | | light years. | | Way. | | | | b. Spiral |Approx. 700,000 |Size and distance |Average |Far external to Milky | (seven hundred | doubtful but | 480 mi. | Way and numerous | thousand) | very great. | | near its poles. | | | | c. Planetary |One hundred and |Several times that |Average |In or close to Milky