A brief sight of something. see or perceive briefly.

expert in or student of astronomy. Scientist studying stars and other bodies in space.

sentence worded or expressed so as to elicit information. What you ask about; issues. To have or express concerns or uncertainty.

likely or prone to be affected by. conditionally upon. The person or thing that does the action of a verb. To cause to suffer or experience something.

Used to add new (often different) information.

small, narrow river. Classes split into ability levels. To send a constant flow of data over the internet.

way in which one acts or conducts oneself.

person who watches or notices. People whose job it is to watch or notice things.

all existing matter and space considered as whole.

positioned in or relating to sky, or outer space as observed in astronomy.

of very distant past. old man.

undergoing natural development by increasing in size and changing physically. Act of cultivating plants for food. To get bigger and more mature; make plants do this.

To feel certain thoughts/emotions for a long time.

document giving authorization. Pieces of paper giving you rights to do some things. To allow something to happen; to give permission.

celestial body moving round star. One of the bodies that orbit the sun.