Mars in the 
Night Sky
Galaxy

 
Mars has fascinated people since the ancient Babylonians, Romans, and Greeks noticed that some of stars in the night sky were "wanderers" and moved relative to the background stars. This is because the planets orbit the Sun (as does the Earth) and are much closer to us relative to the stars in our galaxy. We can see their movement around the Sun over time. 

The planets all appear to move along the same path as the Sun does in our sky. This is because all of planets in our solar system travel the same plane. It is called the plane of the ecliptic. Click here for an interactive view of our solar system. 

As seen in the night sky, planets do not twinkle like stars do. This is because planets are very close compared to stars and the reflected sunlight coming from them is very bright. The stars that we can see from Earth are many trillions of miles away and, as their faint light enters our thick atmosphere, their light becomes distorted and "twinkles." 

COMPARISON

The closest star to Earth is Alpha Centauri, which is 4.3 light years away. A light year is 9.46 trillion kilometers away. That makes Alpha Centauri about 40.1 trillion kilometers away. Depending upon where Mars and the Earth are in their orbits around the Sun, Mars can be as close as 56 million kilometers away and as far as 399 million kilometers away. 

  • How much farther away is Alpha Centauri than Mars on average?

Click for Enlarged Star Chart
(Click image for larger view.)
You can see Mars and some of the other planets in the night sky right now.  Mars is visible in the early morning in the southern part of the sky near Scorpius. During the month of June, it will be nearly twice as bright as Sirius (the brightest star in the sky) as will be quite close to the Earth, about 41,845,000 miles away. Mars is yellow-orange in color. Get up early one morning (when it is still dark) and note in your journal what it looks like. Use this star chart to locate Mars.  The Heavens Above also has a good starchart for viewing many celestial objects including the planets.
If you look for the planets over a period of time, you will notice that they are moving relative to the background stars! If you have spent a lot of time watching the night sky, you will have noticed that stars and planets rise and set like the Sun from east to west. This is because the Earth is rotating on its axis (in a counterclockwise direction if viewed from above the North Pole), which is also the reason we have day and night.

The ancient people did not know that the stars were suns located very far away. They believed the wandering stars (planets) were "gods" and named them such. The brightest was Jupiter (Zeus to the Greeks), the king of the gods. Mars with its reddish color was named after the god of war
  • Why do you think it was called the god of war?

Questions to think about:
  • What color does Mars look like in the night sky near where you live? 
  • How is it different from the stars around it? 
  • How is it different from the other planets you can see?

NEXT...The First Telescopes (1600-1850) -A New View of Mars!