On a dark night of naked eye observation in the Atacama Desert you can see around 2500 stars. Our Galaxy, the milky way, has around 200 billion. To appreciate this, you need a clear sky and low light pollution. One of the places with the best skies for this form of observation is the Atacama Desert in Chile.
In the Atacama Desert in Chile tree factors come together producing the best conditions for naked eye observation. The Humboldt current coming from the Antarctic carries very cold water. This has a strong influence on the water temperature of the Pacific Ocean, keeping them cold and avoiding mass evaporation. The consequence is low air humidity, little cloud formation and almost no rain. The Andes mountain range plays a major role blocking the high humidity air and winds coming from the Atlantic. The Andes mountains and the coastal mountain range block the light of major cities at night avoiding light pollution in the transversal valleys laying in-between. These tree factor make the Atacama Desert in the north of Chile one of the best places on the world for nacked eye observation and stargazing. One of the places to visit if you are a hobby astronomer and a passionate of astro tourism.
You do not need a large telescope to start in the world of astronomy, but you have to go to a good place like the Atacama desert or its vicinity. The most important attractions in the skies of the southern hemisphere are the Via Lactea, the shooting stars, the planets of the solar system and the Magallanic clouds.
The Large vault of stars is visible in more than 330 days in the Atacama Desert due to the special conditions. The probability to observe near planets like Mars or Jupiter is always there, they are quite bright and easy to identify when the sky is clear. The Moon, our natural satellite, can be very bright during the evenings and can dull some weaker stars, however we can enjoy his majesty and without much effort observe its delicate displacement through the night sky.
The Greek astronomer Hipparchus created a scale of magnitudes of brightness to classify the stars from the brightest (Sun) to the weakest. This scale went from 1 to 6. At Present The scale is broader and following their example the brightest stars have lower values. In a clear night in Atacama you can see stars up to magnitude 6.5 and you can even distinguish different colours.
The colour of the stars is a reflection of their temperature. The coolest stars in the universe have a red colour while the hottest stars have a blue colour. In this way astronomers can classify the stars by their brilliance. It is Also possible to estimate its temperature. In a night of observation in the region of Atacama you can do this type of analysis.
Before the telescopes, our eyes were the only instruments to study the sky. Our pupil expands in the absence of light, allowing a greater reception of light. The furthest object observed to naked eye is the Andromeda galaxy, which is located at 2.5 million light-years. In comparison, the closest star, without counting the sun, Proxima Centauri is 4.2 light-years away.
The universe is coarse and wonderful, with impossible distances and infinite time. Astronomy is the science that more humility teaches us, showing how small we can be. Observing the sky is just a small gesture that generates great changes in the way we see the world.
Discover more about astro tourism in the Atacama Desert following this link here.