Intelligent Life in the

GalaxyHANNAH MAGDASOC

MA. HAZEL LLORANDOBSED 2 - R

A being should have…

• An interaction to the environment

• To take in nutrients and energy from the environment

• The ability to reproduce

• The ability to evolve to keep its competitive edge

Life in Earth• The building blocks (amino acids) are

cosmically common. The “miracle” of Nuclei acids (DNA and RNA) with the right message evidently occurred on Earth almost “immediately”

• Although intelligence offers some evolutionary advantage, there has NOT been any steady march towards bigger brains. Humans may be a lucky evolutionary accident.

HISTORY OF THE UNIVERSE

7 PHASES FOF THE COSMIC EVOLUTION

PARTICULATE

Started from a single particle to the

explosion of the big bang.

GALACTIC

Upon the explosion of the big bang,

Galaxies began to form. And one of

them is our galaxy, THE MILKY WAY.

STELLAR EVOLUTION

Stars get brighter as they age along the main

sequence. This results in an outward migration of the “habitable zone”. The continuously habitable zone--the region where

liquid water is always stable—probably only includes 1

planet.

Later positionof HZ

Continuously Habitable Zone

Initial position of HZ

The rate of star formation: 10 stars per year (dividing population of Milky Way

by its present age) Fraction of stars having planetary systems: Most planetary

systems like our own have not been detected yet, but we would expect to be

able to detect those using current methods such as Kepler Telescope.

PLANETARY

Some stars have planetary systems

revolving around them. One example is our

very own, Solar System. If earth, one

of the planets revolving the sun could host life, who knows what the other stars have in

them.

CHEMICAL

There are 92 chemical elements allowed by the laws of physics in this Universe. There is

only one which is capable of making

complex molecules – carbon.

Life is Carbon-based. Click icon to add picture• We see no way that any conceivable life

could be based on any other chemistry than carbon.

• Finding life elsewhere means finding environments where carbon can assemble complex molecules – organic molecules.

• Life as we know it, carbon-based molecules originated in liquid water. That is why scientists are eager to find flowing water on nearby planets, the best example: MARS.

• These molecules occur naturally throughout interstellar space. The organic molecules needed for life to originate were probably brought to the young Earth by comets or meteorites.

Possible life in Mars and Europa• Besides Earth, only two worlds in our solar

system—the planet Mars and Jupiter’s satellite Europa—may have had the right conditions for the origin of life. Mars once had liquid water on its surface, though it has none today. Life may have originated on Mars during the liquid water era.

• Europa appears to have extensive liquid water beneath its icy surface. Future missions may search for the presence of life there.

• Recently, we have discovered that life without the sun is possible. Instead of photosynthesis, organisms have been discovered living in a variety of places via chemosynthesis - the use of chemical energy.

BIOLOGICAL

As organic molecules begin to evolve, new life has formed. Like the species

before the human sprang.

CULTURAL

As life adapts to its environment, it

changes its own features. This

comes the Lamarckian

Evolution and Darwin’s Theory of

Evolution.

Maybe Our Earth is More Rare and Special Than we Thought

• One astronomer calculates that if Jupiter weren’t there, we’d have ~10,000 times higher rate of comet impacts to the Earth.

• Moon needed to stabilize rotation axis and therefore climate. We’re the only inner planet with a real moon, and it took an extraordinary collision to make it.

THE DRAKE EQUATION

N=R* fp n fL fI fc L• R* = rate of formation of suitable

stars

• fp = fraction of these with solar systems

• n = number of life-suitable planets per solar system

• fL = fraction of these planets with life

• fI = fraction of living planets with intelligent life

• fc = fraction of intelligent living planets which choose to communicate across the stars

• L = average lifetime of a communicating civilization

Can be used to estimate the total

number of intelligent civilizations in our Galaxy, although a

number of its factors are extremely

uncertain.

WHAT CAN THEY DO TO CONTACT US?

• EM waves such as radio are “easy” for the persistent (Arecibo can now communicate with a copy of itself on other side of the Milky Way Galaxy!)

• Water hole - is a good place both to broadcast and to seek messages.

But are we sure we want to be contacted? Are you SURE that all advanced ETs are really “nice”

and enlightened?

Galactic Species could be:

• Uninterested

• Maybe they’re too far away to have received the RECENT ‘news’ of our development of technology

• They’re already here, but incompetent or “messing with us”?

• No–UFO’s internally inconsistent

• They are STRICTLY QUARANTINING us

BUT…

Until proven otherwise, this may be the only place in the entire Universe where consciousness has developed. We certainly can’t count on a bunch of super/enlightened beings to swoop down and ‘save’ us just at the brink of some calamity, cures cancer, etc—even if ‘they’ are watching, WE’RE ON OUR OWN.