How is it possible for their to be life on Earth...yet not anywhere else in our solar system...
What is the Goldilocks principle?
The classic fairytale 'Goldilocks and the Three Bears' tells the story of a young child who wanders into a strange house in the woods. She finds one bowl of porridge too hot, another too cold and the third 'just right.'
Astronomers sometimes apply the tale to a planet's ability to sustain life as we know it. In our own star system, Venus is too hot and Mars is too cold for us -- but Earth is just right. We are just the perfect distance from the sun to allow liquid water, which allows plants to grow, in turn supplying animals with oxygen.
Broadly speaking, the Goldilocks principle applies to any situation where only a particular range of conditions is agreeable.
Protection by the Atmosphere
Earth’s moon receives about the same amount of sunlight as Earth. Yet conditions on the Moon are more extreme than they are on Earth. The
Moon’s surface temperature can rise to 100°C during the day and drop to −150°C at night.Temperatures are extreme on the Moon because the
Moon, unlike Earth, does not have an atmosphere.
Maintains Temperatures
Earth’s atmosphere is like a blanket around Earth. It absorbs sunlight during the day and keeps heat from escaping into space during the night. It maintains Earth’s average surface temperature at a comfortable 14°C.
2. Reading Check How is Earth’s atmosphere like a blanket?
Absorbs Harmful Radiation Have you ever had a painful sunburn? Sunburns are caused by the Sun’s ultraviolet light. Even though you cannot see ultraviolet light, you can feel its effects. Too much ultraviolet light can harm you.
Fortunately, Earth’s atmosphere absorbs most of the Sun’s ultraviolet light, as well as x-rays and other harmful light from the sun
The atmosphere also helps protect Earth from highly charged particles that erupt from the Sun in powerful storms.
Burns Up Meteoroids Earth’s atmosphere also protects Earth’s surface from meteoroids. Millions of meteoroids strike Earth’s atmosphere every day. But almost all of them burn up in the atmosphere before they can hit Earth’s surface.
Traveling to space...
Why wear Spacesuits?
Space travelers wear a spacesuit in order to bring along elements of Earth’s environment needed for survival: oxygen, air pressure, moderate temperatures, and protection against the Sun’s rays. On earth, our atmosphere absorbs much of the sun;s harmful rays. In space and on planets the thin atmosphere provides little protection for astronauts.
The vacuum of space is another harsh environmental condition, causing fluids to boil due to lack of air pressure. Bubbles form in the bloodstream and tissue, capillaries and other fragile tissues would rupture. Lack of oxygen would render the unfortunate individual unconscious in 15 seconds and permanent brain damage in as little as 4 minutes, followed shortly thereafter death.
Key Question
What function does a spacesuit need to have for a mission to mars?
Spacesuit Criteria
1. Function on Mars.
2. Have features needed to accommodate human body functions.
3. Take into account Mission Control needs.
4. Allow astronauts to perform mission tasks. (climb, repell, dig, collecting rocks ,ice, etc.)
Q & A
Why do humans need to wear spacesuits?
How is movement in space different from movement on Earth?
What does a spacesuit have to include?
A system for breathing, air pressure, temperature control, walking, identification, food storage…can you think of any more…
How can a spacesuit make work harder to complete?
Bulky because of the many systems and stiff due to air pressure.
Why don’t astronauts need to wear a spacesuit in a spacecraft?
How does a spacesuit worn in space differ from those needed for Mars?
Mars needs suits that function below freezing, with adaptations for fine dust particles that could affect visibility and leak into suit joints. Both need oxygen.
Mission Control
Mission Control plays a critical role in keeping astronauts safe and helping them complete tasks during extravehicular activities (EVA’s) or spacewalks. Spacesuits need to have special features so that Mission Control can be sure the suits are functioning well. They also need to communicate with and identify the astronauts.
References
Life in Our Solar System - Click here
Space Travel - Click here
Let's Explore Space Travel - click on the links below
First we must build a spacesuit!
Astronomy Training
Life in Space
The 10 Coolest Space Suit Designs
Spacesuit Design Q & A
Elements of Spacesuit Technology
Everything you wanted to know about Spacesuits and Spacewalks
Clickable Spacesuit
Spacewalk Video