Remember the old fairy tale, “Goldilocks and the Three Bears”? Goldilocks tried all the chairs, beds and bowls of porridge until she found the ones that were “just right”. Well, in astrobiology, we also use the term Goldilocks when talking about other planets that could possibly sustain life.
The Goldilocks Zone refers to the habitable zone around a star where the temperature is just right – not too hot and not too cold – for liquid water to exist on a planet. Watch the “Watch This Space” video that explains Exoplanets in Goldilocks Zones of their star systems.
Liquid water is essential for life as we know it. Where we find liquid water on Earth we also find life. Looking for planets in the Goldilocks Zone allows scientists to hone in their search for Earth-like planets that could contain life.
Basically, the assumption is that if it’s possible there may be liquid water on the planet, then it’s also possible that the planet may be habitable. But, just because a planet or moon is in the Goldilocks Zone of a star, doesn’t mean it’s going to have life or even liquid water. Click here for more details!
After all, Earth isn’t the only planet in the Sun’s Goldilocks Zone – Venus and Mars are also in this habitable zone, but aren’t currently habitable.
Activity
Imagine as if you are part of the crew that will travel to the closest Exoplanet in a Goldilocks Zone. The planet is dense with plants and has an atmosphere similar to Earth’s. There are large bodies of shallow water along its equatorial region. You and the crew are tasked with the main mission objective of finding evidence of life, observing it and classifying it.
To earn credit for this activity, write three journal entries from different points in the fictional mission.
Entry 1-Explain where your habitation module is located. What is around you? What can you observe from your vantage point? Explain the environment in sensory terms (temperature, atmospheric conditions, what you can see, smell and hear).
Entry 2-Focus on one new life form. How does it behave? How does it interact with its environment? What does it seem to require for life? Will it require water and an energy source to maintain life or is this new planet completely different from life as we know it?
Entry 3-Explain this life form in terms of a food web/food chain. You should be using terms such as predator, prey, tertiary consumer, decomposer and energy. Describe the interactions between this organism and how it receives its energy. How does it interact with other organisms (if any) in its environment? Does it have specialized structures to keep it safe or to catch prey?