YOU probably didn't notice the tennis court-size experimental balloon pass over Hervey Bay on Wednesday.

Floating over the Fraser Coast at an altitude of 19km, the balloon is part of Project Loon, a futuristic concept from the owners of Google to provide "balloon-powered internet" on a global scale.

The balloons are described as floating telephone towers which transmit high speed internet from the edge of space to users on the ground.

The mission is designed to extend internet connectivity to people in rural and remote areas worldwide.

The balloon's passover didn't slip under John Sahlberg's radar, who noticed it on flight tracking website FlightRadar24 travelling over Burrum Heads, Pt Vernon and then Fraser Island in the morning.

"I've seen a few of them, but nothing as close as that to Hervey Bay," the Urangan resident said.

The innovative project started in 2013 and has been launching balloons across Australia, New Zealand and South America ever since.

The internet balloons are designed and manufactured to survive the harsh conditions in the stratosphere, where winds can blow over 100 kmh while the thin atmosphere offers little protection from UV radiation and temperatures reach as low as -90 degrees.

Made from sheets of polyethylene, each balloon is built to last more than 100 days in the stratosphere before returning to the ground in a controlled descent.

FUN FACTS

• EACH balloon has a coverage area of 5000km2.
• Once the balloon lands, recovery teams then collect the equipment for reuse and recycling.
• By moving with the wind, the balloons can be arranged to provide coverage where it's needed.
• The project was started in 2013 by the parent company of Google.

Have you spotted something out of the ordinary? Let us know at editorial@ frasercoastchronicle.com.au