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Flashcards in Lecture 9 Deck (13):

What is unique about bacteria?

They do not require light, they could potentially use cosmic rays to make energy


What are cyanobacteria?

Bacteria who live deep underground and undergo anoxygenic photosynthesis


What are the three major branches of Darwin's tree of life

Bacteria, Archaea, and Eukaryotes


How does the bacteria feed on chemical radiation?

It uses the energy from chemicals broken down by radiation


What planets would be ideal for these bacteria?

Mars and rogue planets


What was unique about Newton's law of universal gravitation?

it implies that the moon (very far away) must feel gravity


What are the three important concepts in the Universal Law of Gravitation?

1. Every mass attracts every mass 2. attraction is directly proportional to masses 3. attraction is indirectly proportional to distance


How did newton's laws extend kepler's first law?

Now applies to all orbiting objects (not just around the sun)


How did newton's laws extend kepler's second law?

Now applies to all orbiting objects in a field with a central force, incl. gravity


How did newton's laws extend kepler's third law?

Ellipses are not the only paths for orbitals, (E<0, ellipses; E=0 parabola; E>0 hyperbola)


How was G first measured?

In the Cavendish experiment


How can we determine the mass of large objects?

By using the orbital period and average orbital distance (e.g. the earth and sun, earth's mass would be negligible)


What is fundamental about orbital energy?

it remains constant, unless there's an external force