Class Notes (834,037)
Canada (508,290)
Lecture 7

Lecture 7 Habitable Planets.docx

13 Pages
Unlock Document

Life Sciences
Luc Bernier

Habitable Planets Only EarthUntil now the only example of a known habitable planetEarth orbits the Sun within a region called the habitable zoneWhat is the habitable zoneRegion where an Earth analog planet can maintain liquid water on its surface It has the greenhouse gases that keep the temperature regulated for life on Earth Liquid Water Important for HabitabilityThe best solvent for life to emerge and evolve inSeveral key characteristics o It has a large dipole moment o It can form hydrogen bonds with other water molecules o It is able to attractrepel molecules in a hydrophobichydrophilic fashionLiquid Water Important for HabitabilityWater abundant compound in our galaxyCan be found in different environments o Stellar atmospheres The Habitable Zone HZInner edge of the HZ o Runaway greenhouse conditions o Planets such as Venus and Mercury are found in the inner edge of the HZOuter edge of the HZ o Greenhouse effect fails to keep the planet above the freezing point o Planets such as Neptune and Saturn would be an example of this PictureEarth has the perfect distance from the sun It received the perfect amount of energy to keep things warm but not too hot where water is lost as water vapourIf we go outside these gases such as carbon dioxide condense and they cant perform their function as greenhouse gasesIf the mass of the star sun increases the HZ is further to the rightIf the star is smaller the HZ is located close to the star leftBasic Habitability Requirements for LifeMain factors o Long time span o Liquid water in contact with building blocks o Environmental conditions that allow liquid water to existBuilding blocks for life to exist need to be abundant at the surface o Carbono Sulphur o NitrogenFor the most part the overall conditions were relatively stable in the Cambrian eraThis has led to the process of evolution to take shape and formEnvironmental conditions that allow liquid water to exist
More Less

Related notes for LIFESCI 2H03

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.