WALLABY

A radio telescope in remote Western Australia is helping to build a 3-dimensional map of the night sky, mapping nearby galaxies up to a billion light years away.

About WALLABY:

• WALLABY is a radio telescope in Western Australia that is helping astronomers build a three-dimensional map of the night sky.
• The Widefield ASKAP L-band Legacy All-sky Blind Survey (or WALLABY) is one of two key surveys that are now running on the Australian SKA Pathfinder (ASKAP).
• It is an innovative imaging radio telescope located in an extremely radio-quiet zone (the Murchison Radio-astronomy Observatory) in Western Australia.

Aim of WALLABY:

• To observe three-quarters of the whole sky in the 21-cm line of neutral hydrogen (or HI) at 30-arcsec resolution.
  • thereby detecting and imaging the gas distribution in hundreds of thousands of external galaxies in the local Universe.

• It will help the researchers to measure:
  • measure the dark-matter distribution
  • the internal motion of galaxies
  • how these systems evolve and interact

What is radio astronomy and how is it used?

• The radio telescope is an astronomical instrument consisting of a radio receiver and an antenna system that is used to detect radio-frequency radiation between wavelengths of about 10 meters (30 megahertz [MHz]) and 1 mm (300 gigahertz [GHz]) emitted by extraterrestrial sources, such as stars, galaxies, and quasars.
• Unlike optical telescopes, radio telescopes can detect invisible gas and, therefore, can reveal areas of space that may be obscured by cosmic dust.
• Cosmic dust consists of tiny particles of solid material floating around in the space between the stars.
• In its simplest form a radio telescope has three basic components:
  • One or more antennas pointed to the sky, to collect the radio waves
  • A receiver and amplifier to boost the very weak radio signal to a measurable level, and
  • A recorder to keep a record of the signal.