the universe in your backyard
DESCRIPTION
“Poets say science takes away from the beauty of the stars - mere globs of gas atoms. I, too, can see the stars on a desert night, and feel them. But do I see less or more?” - Richard P. Feynman We all have wondered about the origins of our universe. How did it all begin? What do we see when we look up at the night sky? What exactly is dark matter? Are there more universes out there? What about aliens? Jaya — a student of astronomy — is on her way to discovering the answers to these questions and unravelling other mysteries of our universe. She’s here this weekend to share what she’s learnt so far with us. Date: Saturday, January 8, 2011 Time: Presentation at 8:00 PM, followed by a discussion, dinner and some star-gazing. Venue: Tunnel Top, Mini Matheran ResortTRANSCRIPT
the universe in your backyardProjector Friday with Jaya RamchandaniJanuary 8, 2010(Near) Mumbai
Astro-talk
Big Bang Theory
Dark Energy
Relativity
Hindu Cosmology
Today’s talk
Future of the Universe
Alien-where
Stars and Constellations
Galaxies
Our Solar System
8:00 PM
Planet Jupiter and its moons (Io,
Europa, Ganymede, and Callisto)
10:00 PM
Andromeda M31 (largest galaxy in
our local cluster)
Open Star Cluster Plaides
tonight’s observations
12:00 AM
Orion Nebula (M47), M37, M35
2:00 – 3:00 AM
Saturn
6:00 AM
Venus
What is Light?
Energy travels in waves at the speed of light (300,000 km/sec)
1 Light Year = How far light travels in one year = 9.4605284 ×
1015 meters
What is Light?
Distances in cosmology
Sun’s nearest brother is 4.24 light years away or 40,000,000,000,000 km away.
What’s in an atom?
The forces of nature
A human being is part of a whole, called by us ‘universe’, a part limited in time and space.
~Albert Einstein, Founder of the Big Bang Cosmology
Galactic redshift (universe is expanding)
Cosmic background radiation
Observation of Helium which agree with the standard Big Bang model.
Evidence for big bang
Radio Telescopes
Secret to these observations
Space Telescopes
Composition of the current universe
Dark Energy73%
Dark Matter23%
“Normal Matter”4%
What is dark energy?
Dark energy is a hypothetical form of energy that permeates all
of space and tends to increase the rate of expansion of the
universe. In the standard model of cosmology, dark energy
currently accounts for 73% of the total mass-energy of the
universe.
What is dark Matter?
Dark matter is matter that is inferred to exist
from gravitational effects on visible matter and background
radiation, but is undetectable
by emitted or scattered electromagnetic radiation.
Travel to the Stars?• Kinetic Energy = 1/2 Mv2
• What does it take to get a 1000-ton spaceship to 10% of the speed of light? (43 years to Alpha Centauri)
• M=106 kg, v = 3 x 107 m/sec• KE = 1/2 x 106 x 9 x 1014 = 4.5 x 1020 joules• Equals U.S. Energy Production for 4.5 years• Once you get there, you have to stop.
Hindu cosmological time cycle
Vedic and Puranic units of time span from the truti (microsecond)
to the mahamanvantara (311.04 trillion years). Hindu theology
considers the creation and destruction of the universe a cyclic
process
trasarenu is the combination of 6 celestial atoms.
truti is the time needed to integrate 3 trasarenus, or
1/1687.5th of a second.
Hindu cosmological time cycle
50 years of Brahma have elapsed and we are in the first Day of
the 51st year.
This Brahma's day, Kalpa, is named as Shveta Varaha Kalpa.
We are in the Kaliyuga of the 28th Mahayuga. This Kaliyuga
began in the year 3102 BC
The time elapsed since the current Brahma has taken over the
task of creation can be calculated as 155.52 Trillion Years
We perceive the Universe in four
dimensions: x, y, z, t
But there are problems because of
the conflict between general
relativity and quantum theory
“There can’t be a singularity at the
instant of the Big Bang…”
What about string theory?
What about string theory?
This (and other considerations) have led to the idea of cosmic strings
occupying a 10-dimensional space…
The MultiverseAre multiple universes possible?
• Trillions of years: Star formation ends• 10-100 trillion years: Stars stop radiating• 1015 – 1020 years: Planetary orbits decay• 1032 – 1041 years: Protons decay• Heat Death?• Big Crunch?• Big Bounce?
How will it all end?
Frank Drake developed Drake’s Equation
N = Ns*fs-p*fp-e*fp-l*fl-i*fi-c*Tc / Tg
N = # of communicative civilizations in our galaxy, right now
Will you ever see an alien?
Ns = number of stars in the Galaxy
fs-p = fraction of stars with planets
fp-e= fraction of planets that are “earthlike”
fp-l = fraction of “earthlike” planets that develop life
fl-i = fraction of above that develop intelligence
fi-c= fraction of above that develop communication
Tc = lifetime of communicative civilization
Tg = age of Galaxy
Drake’s equation
N ~ 10000
Say the galaxy contains ~ 10^11 stars, if N ~ 104, we
would expect to have to survey ~10^7 stars before we
found one ETI.
Even then, ETIs will rarely co-exist at the same time.
“We may really be alone…we should have a better picture in
the next 50 years if we use instruments with fast survey
speeds.” – My radio astronomy professor
Solving drake’s equation
A large ball of gas that is held together by gravity
Formed from nuclear fusion
Nuclear fusion produces tremendous energy (stars
shine because of this energy)
High temperature and high pressure
Anatomy of a star
28
a star’s life
Star classification
Constellations: Recognizable patterns
in the sky are called Constellations.
There are 88 Constellations: Orion,
Leo, Aries, Taurus, etc. 12 are based on
the Zodiac.
Asterisms: Recognizable patterns of
stars that are not one of the
constellations are called Asterisms: Big
Dipper, Little Dipper, Summer Triangle
constellations
The zodiac
The zodiac is the ring of constellations that lines the ecliptic, which is the
apparent path of the Sun across the celestial sphere over the course of
the year.
The band of light called the “Milky Way” traces the galactic plane as it appears from our location in the outskirts of the galaxy.
The milky way
Other types of galaxies
Spiral Elliptical Irregular
The local group
The local super cluster
Large scale structure
• Cloud of “dust” starts to pull
in and contract due to
gravity
• Nuclear fusion starts the sun
• Loose rock starts to pull
together to form the planets
• Solar system forms – about
5.5 billion years ago
• Earth is about 4.6 billion
years old
Formation of our solar system
Our planets
Interesting video clips
Can a Planet Have Two Suns?
Why Isn’t Pluto a Planet Any More?
Why Is the Sky Blue?
Why Doesn’t the Moon Fall Down?
What Will Happen to the Earth When the Sun Dies?
Do the Stars Really Move?
Where Is the Center of the Universe?
What Causes an Eclipse of the Moon?
Why Does the Moon Look Like It Changes?
ThankYou!