Square Kilometre Array Science

PowerPoint Presentation

Square Kilometre ArrayScienceStephen FineSKA FellowUniversity of the Western Cape

SKA Science goalsCosmology + Galaxy evolution

Testing general relativity: gravity waves

Magnetic fields in the Universe

Exoplanets and SETI

The first light in the Universe.EVER?Note 12Cosmology + Galaxy evolution`If you want to make an apple pie from scratch, you must first create the Universe.

`You have to know the past to understand the present.

Carl Sagan (1935-1996)Telescopes as time machinesSpeed of light:299,792 km/s

You see this slide ~ 0.00000003 seconds(30 nanoseconds) in the past.

Astronomers like distances measured in lightyears1 ly = 9,460,000,000,000 km

Telescopes as time machinesProxima centauri4.24 ly

Telescopes as time machinesProxima centauri4.24 ly

Telescopes as time machinesEta Carina7500-8000 ly

Telescopes as time machinesAndromeda galaxy2.2 Mly

Cosmic timelineEarthDistance = 0 lyAge = 13.7 billion yearsBig BangDistance = 13.7 billion lyAge = 0Between here is the whole history of cosmic evolution

Back to galaxy evolutionIn the nearby Universe we have a fairly good understanding of the demographics of galaxies.

0.4 billion years

Galaxy evolutionStepping out we have optical surveys that can find large numbers of galaxies when the universe was ~4/5th its current age.2.5 billion years

Galaxy evolutionWith the largest telescopes we can find massive galaxies when the Universe was ~1/10th its current age.12.7 billion years1 billion years after BB

Galaxy evolutionWe know that galaxies had not started forming until at least 0.2 billion years after the Big Bang.13.5 billion years0.2 billion years after BB

The state of the artNo galaxiesSome massive galaxies formedLimit of current large galaxy surveysLimit of current galaxy mass surveys

Enter the SKANo galaxiesSome massive galaxies formedLimit of current large galaxy surveysLimit of current galaxy mass surveysA mass survey over half the observable UniverseWill detect `typical Milky Way type objects as they are first forming

Enter the SKANo galaxiesSome massive galaxies formedLimit of current large galaxy surveysLimit of current galaxy mass surveysA mass survey over half the observable UniverseWill detect `typical Milky Way type objects as they are first formingSETI with the SKA

Project Cyclops

Project Cyclops

Remind you of anything?

Some estimates for SKA SETITerrestrial TV/radioCould be observed from ~75 ly

~2500 stars in that volume

~250 are sun like.(Most others too faint)

Some estimates for SKA SETIRadar (especially military)Could be observed from a few hundred ly

~10000 stars in that volume

~1000 are sun like.

Final commentsFinal comments