An Updated Drake Equation

The original Drake equation is essentially correct but it might be more useful if it were broken down into finer steps. Each step being achievable and measurable as we learn more about the universe.

constraints: milky way only, and ignoring the possiblity of marine life in "frozen" bodies like Io

• number of regions cleared of GRB or other unsafe galactic sized events / galaxy
• number of regions free from supernova (for billions of years) / safe region
• number of regions containing heavy elements (second or later generation stars) / safe region
• number of stars / heavy region
• number of stable solar systems (post bombardment) / stars

• number of planets / solar system
• number of planets in the goldie locks zone (or sufficiently heated for liquid chemistry) / solar system
• number of goldie locks planets w/ magnetic core (to protect the atmosphere) / solar system
• number of protected planets w/ plate tectonics (to recycle the surface) / solar system
• number of recycled planets w/ a slow orbit / solar system

• number of planets w/ some kind of liquid (e.g. water)
• number of goldie locks planets w/ atmosphere
• number of atmospheric planets w/ stable climate
• number of atmospheric planets w/ abundant minerals (e.g. CHNOPS)

• number of planets w/ single cell organisms
• number of planets w/ multi cell organisms
• number of planets w/ plants
• number of planets w/ animals
• number of planets w/ intelligent animals
• number of planets w/ technologically advanced beings