Venus is usually visible to the naked eye. ... It is commonly referred to as the Red planet. ... When it is in the nighttime sky, Mars is easily visible for the naked eye. ... In the nighttime sky, Saturn is easily visible to the naked eye. ...

• Word Count: 677
• Approx Pages: 3
• Grade Level: High School

Introduction Since ages Space have been a mysterious and interesting subject that we human beings only could stare at, until the development of the telescope all astronomical observations were made with the eye. ... The human eye with 20/20 vision, the angular resolution is 1 arc minute, which is 1/60th of a degree. ...

• Word Count: 3931
• Approx Pages: 16