the universe in your backyard

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the universe in your backyard Projector Friday with Jaya Ramchandani January 8, 2010 (Near) Mumbai

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“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 Resort

TRANSCRIPT

Page 1: The Universe in Your Backyard

the universe in your backyardProjector Friday with Jaya RamchandaniJanuary 8, 2010(Near) Mumbai

Page 2: The Universe in Your Backyard

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

Page 3: The Universe in Your Backyard

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

Page 4: The Universe in Your Backyard

What is Light?

Page 5: The Universe in Your Backyard

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?

Page 6: The Universe in Your Backyard

Distances in cosmology

Sun’s nearest brother is 4.24 light years away or 40,000,000,000,000 km away.

Page 7: The Universe in Your Backyard

What’s in an atom?

Page 8: The Universe in Your Backyard

The forces of nature

Page 9: The Universe in Your Backyard

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

Page 11: The Universe in Your Backyard

Galactic redshift (universe is expanding)

Cosmic background radiation

Observation of Helium which agree with the standard Big Bang model.

Evidence for big bang

Page 12: The Universe in Your Backyard

Radio Telescopes

Secret to these observations

Space Telescopes

Page 13: The Universe in Your Backyard

Composition of the current universe

Dark Energy73%

Dark Matter23%

“Normal Matter”4%

Page 14: The Universe in Your Backyard

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.

Page 15: The Universe in Your Backyard

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.

Page 16: The Universe in Your Backyard

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.

Page 18: The Universe in Your Backyard

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.

Page 19: The Universe in Your Backyard

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

Page 20: The Universe in Your Backyard

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?

Page 21: The Universe in Your Backyard

What about string theory?

This (and other considerations) have led to the idea of cosmic strings

occupying a 10-dimensional space…

Page 22: The Universe in Your Backyard

The MultiverseAre multiple universes possible?

Page 23: The Universe in Your Backyard

• 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?

Page 24: The Universe in Your Backyard

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?

Page 25: The Universe in Your Backyard

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

Page 26: The Universe in Your Backyard

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

Page 27: The Universe in Your Backyard

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

Page 28: The Universe in Your Backyard

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a star’s life

Page 29: The Universe in Your Backyard

Star classification

Page 30: The Universe in Your Backyard

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

Page 31: The Universe in Your Backyard

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.

Page 32: The Universe in Your Backyard

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

Page 33: The Universe in Your Backyard

Other types of galaxies

Spiral Elliptical Irregular

Page 34: The Universe in Your Backyard

The local group

Page 35: The Universe in Your Backyard

The local super cluster

Page 36: The Universe in Your Backyard

Large scale structure

Page 37: The Universe in Your Backyard

• 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

Page 38: The Universe in Your Backyard

Our planets

Page 40: The Universe in Your Backyard

ThankYou!