10/15/2012

Alec Fisher

QUASARS(QUASI-STELLAR RADIO SOURCES)

INTRODUCTION• What are they?

• How were they discovered, and by whom?

• How do they work?

• What do they say about our Universe?

(2) Artists Rendition of a Quasar

THE DISCOVERY• The late 1950’s

• Radio Telescopes

• Lovell Telescope

• No objects could

be found to match

radio signatures

(3) The Dwingeloo Radio Telescope

3C 48 - 1960

• First of these faint

radio sources to have

an object with it

• Many unknown

emission lines

• Astronomer John

Bolton said Red-Shifted

(4) Quasar 3C 48 viewed in the Radio Spectrum

3C 273 - 1962• Object was expected to make 5 occultations with the moon

• Astronomers Cyril Hazard and John Bolton use Parkes Radio Telescope

• Maarten Schmidt uses 200 inch Hale to obtain optical spectrum

• Shifted Hydrogen

(5)Spectral lines becoming progressively more redshifted

• What does this huge redshift imply for quasars?• 3C 48 red shifted .378 and Quasars have been found with redshift as high as z=7• Very far away• Farthest Quasar away is 12.9 Billion light years• Hubble’s Law

WHY SO LUMINOUS?• 3C 273 has an absolute magnitude of -26.7 and 4 trillion times brighter than the sun.

• Most luminous objects in the known universe

• Appear as point sources, like stars, as opposed to extended sources, such as galaxies

• Unknown form of antimatter

• White holes

WHAT EXACTLY ARE THESE OBJECTS?• Accretion disk models were successfully completed in the 1970s

• The energy emitted in relativity jets would explain why Quasars are so luminous

• Can convert 10% of mass into energy, as opposed to p-p chain nuclear fusion.

ACTIVE GALACTIC NUCLEUS!• Quasi-stellar objects are the active nuclei inside

newly formed galaxies.

• Accretion disk on the supermassive black hole in the nucleus.

• Periods of growth for the black hole.

(6) An artists drawing of a Quasar and a Blazar

WHY AREN’T ALL GALAXIES QUASARS?

• Need to consume at least 10 solar masses

• Most Luminous consume 600 Earths a minute

• Become normal galaxies after material is exhausted.

(9) What we think the milky way galaxy looks like

HOW DOES THIS KNOWLEDGE HELP US?• Objects appear to us how they did at the beginning of the universe.

• Lets us see how galaxies act at the beginning of their creation.

• Proved Einstein’s theory of General Relativity.

(10) Curvature of Space-Time

(11) Twin Quasar that proves Einstein’s Theory

(12) The Einstein Cross

CONCLUSION• Quasars are active galactic nuclei that are extremely bright and distance, making them useful

reference points in establishing a measurement grid on the night sky.

REFERENCES• (1)http://en.wikipedia.org/wiki/Quasar#History_of_observation

• (2)http://www.google.com/imgres?q=quasar&num=10&um=1&hl=en&biw=1600&bih=775&tbm=isch&tbnid=9HdPRtqY0sGyaM:&imgrefurl

• (3)http://www.flickr.com/photos/59371508@N07/galleries/72157628248518759/

• (4)http://en.wikipedia.org/wiki/3C_48

• (5) http://www.schoolphysics.co.uk/age14-16/Astronomy/text/Red_shift/index.html

• (6)http://astronomycentral.co.uk/most-distant-quasar-discovered/

• (7)http://www.astronomy.com/en/News-Observing/Ask%20Astro/2011/01/Blazar%20vs,-d-,%20quasar.aspx

• (8)http://en.wikipedia.org/wiki/Supermassive_black_hole

• (9)http://www.astronomy-blog.com/blogs/permalinks/8-2006/hidden-milky-way-deuterium-found.html

• (10)http://en.wikipedia.org/wiki/Gravitational_lens

• (11)http://en.wikipedia.org/wiki/Twin_QSO

• (12)http://en.wikipedia.org/wiki/Einstein_Cross