A huge balloon examining a black hole passes over Nunavut before landing in the Northwest Territories

From the ground, it looked like a second moon floating in the sky.

A football stadium-sized research balloon recently passed over Nunavut and the Northwest Territories to survey the galaxy and create a buzz in some of the communities it passed through.

The Calibur XL – launched from Kiruna, Sweden, last week – was built by a team of 50 scientists from the United States, Japan and Sweden to measure X-rays from black holes and neutron stars.

The trip took six days, seven hours and 45 minutes and was a collaboration between NASA, Washington University in St. Louis (WUSTL) and the KTH Royal Institute of Technology in Sweden.

The ball, which is the size of a football stadium, was photographed at 130,000 feet by Richard Bose, a senior research engineer at the University of Washington who helped build the telescope it was carrying. (Submitted by Richard Bose)

A Twitter account for the XL-Calibur shared photos that were taken by people in Norway, Iceland and Arviat and Iqaluit in Nunavut. The balloon also passed over Yellowknife before Richard Bose, senior research engineer at WUSTL, said the payload landed 80 kilometers from Délı̨nę in the Northwest Territories on Monday.

Bose said NASA decided when to end the flight, a process that involved opening a hole in the balloon for it to fall from an altitude of 130,000 feet to around 50,000 feet. Then the balloon and the telescope separated — the latter being transported to the ground with a parachute.

“I just missed a few trees and definitely didn’t land in a lake, which is our biggest concern,” said Bose, who helped build part of the telescope and said the water didn’t probably wouldn’t have been kind to rare and expensive mirrors. contains.

The XL-Calibur was spotted drifting over Iqaluit last Friday. (Karen Pikuyak/CBC)

Jeremy Eggers, a NASA communications manager, told CBC News in an email that the polythene film balloon landed nearly 20 kilometers from the payload and a team was deployed to recover the three parts.

Before ending any flights, Eggers said NASA’s science balloon team was carrying out a survey to ensure public safety, minimize environmental impacts and ensure they could salvage as much equipment as possible. .

“NASA considers environmental impacts during all science balloon missions and takes steps to mitigate the impacts,” he wrote, adding that the organization had worked with Canadian officials to coordinate the flight and landing location of XL-Calibur.

Bose said XL-Calibur’s primary target is a black hole called Cygnus X1 which is special because it is sucking up gas from a nearby star.

The line on this map shows the flight path of the XL-Calibur from Sweden, over Norway, Iceland and northern Canada. (Columbia Science Balloon Facility)

“Black holes are very mysterious objects and of course you can’t really tell what’s going on there because light can’t escape,” he said. But scientists can study things happening near them, he said, like something “very intense” generating X-rays near Cygnus X1.

“In the spirit of exploring and understanding what is happening in our universe, this is some of the fundamental research that we are fortunate to be able to fund.”