Vanessa Chapman's Radio Telescope Is Made From Upcycled Food Packaging and an Empty Fuel Tin

Vanessa Chapman has demonstrated that you don't need a big budget to get into radio astronomy, creating a functional hydrogen-line radio telescope out of a low-cost software-defined radio (SDR) dongle and salvaged packaging.

Built as part of a community science project run by Space Australia, Chapman's telescope is made to a definite budget. "Vanessa's telescope is constructed using cereal boxes that have been folded into shape," Space Australia's Rami Mandow explains, "covered with aluminium foil (for reflectivity) and joined together to form a conical horn that directs radio waves into the waveguide.

"The waveguide itself is produced by inserting a short copper-wire antenna into a disused circular paint can, before connecting this to the low-noise amplifier and receiver."

The salvaged materials are combined with an RTL-SDR software-defined radio dongle, plus an RTL-SDR wideband low-noise amplifier, connected to a controlling PC. The entire assembly is then used for hydrogen line observation — detecting the electromagnetic signal on the 21cm wavelength through which the approach or departure of Milky Way galactic features can be tracked.

Chapman's build is the first of 35 DIY radio telescope builds being put together as part of Space Australia's SpaceAusScope project, which launched in December last year; the build phase is scheduled to close at the end of March, with the observation phase beginning in April. "By the end of the community science project SpaceAustralia.com aims to have documentation available for a variety of DIY radio telescope models for future builders," writes Mandow, "esp. school students across the country."

Additional information on the build and the project in general can be found on Space Australia, with more on the radio hardware and hydrogen line observation on RTL-SDR.com.