In 1974, humans sent a message to space. The Arecibo Radio Telescope, located in Puerto Rico, was celebrated as the first telescope to send a message because many people at the time thought that we, as humans, weren’t the only species to exist in the universe. At least, not the only intelligent species, in spite of the fact that some scientists and researchers thought we’d give away “Earth’s location in space to unknown alien civilizations,” and open us up for an attack.
Today, however, we now know that the radio signals we sent then aren’t so scary. But the radio signals we received from space back then are a totally different story. The “fast radio bursts” are from 17 years ago in fact from the 64-meter Parkes radio telescope in Australia. Researchers couldn’t figure out where the signals came from back then and searched almost two decades to do so. Today, however, they have their answer.
Researchers knew that the radio signals were “reasonably local, say within 5 km of the telescope,” according to Simon Johnson, the head of CSIRO’s astrophysics department. The researchers initially thought the signals came from lightning strikes because of the type of signals they found – perytons – and the time of year they found them at 2.4 GHz.
Ironically, it was the Parkes’ observatory’s microwave oven that generated the radio signals that the staff used to hear up their lunches.
So, why didn’t the microwave show these signals when it was tested? Because apparently, it only gives off the signals at certain times. Such as when you open the microwave oven door while the cycle is still running – before it finishes.
According to Johnston:
“If you set it to heat and pull it open to have a look, it generates interference.”
It’s that interference that creates the perytons. And because people don’t live at the observatory, they only figured it out now, 17 years after they initially detected them, what they were and where they came from. And only after a new receiver was installed.
Additionally, according to the report, the fast radio burst signal interference only ever happened when the telescope was made to point in the direction of the microwave the staff used, and only when the staff was on the premises during work hours.
According to Johnston:
“When you only find a few, it’s hard to pin them down.”
And, to date there have only been a “few.” The Parkes telescope was “built in the middle of nowhere,” which was initially quiet and allowed researchers to work without interference. However, interference from the surrounding towns and newer technology such as FM radio, digital technology, and even wireless and Bluetooth technologies have made detecting the FRB signals more difficult.
A new telescope is being built called the Australian Square Kilometre Array Pathfinder, or ASKAP in Western Australia. Johnston says it is:
“The quietest site on Earth to do astronomy. There’s no mobile phone coverage, no radio station, no Wi-Fi – it’s pristine and quiet and we can look into the universe and see things that you can’t in Parkes.”
Essentially, the site of the new telescope is located in a “radio quiet zone” protected from outside interference and technologies. No one will be able to enter the area without proper licensing for any “wireless internet or radios,” making it easier for researchers to detect a fast radio burst.
The question is… Does that mean the staff can’t use microwaves any longer either?
Featured Image by NASA, ESA, J. Hester and A. Loll (Arizona State University)
via Wikimedia Commons/Public Domain