NASA X-Calibur: Black hole seeking telescope carried by giant balloon

High pressure helium is used to inflate the balloon that will carry X-Calibur high into the atmosphere. 

This photo of the balloon was taken during a previous mission in Antarctica. 

Credit: NASA

Scientists from NASA's Scientific Balloon Facility and University of Washington in St. Louis will soon launch a telescope with a giant balloon, planning the launch for sometime later this month.

Reaching heights of around 120,000 feet, the balloon will carry a polarimeter telescope meant to search for black holes.

X-Calibur, a polarimeter telescope measures a powerful kind of X-Ray that is emitted by objects being pulled into a black hole.

Black holes don't even let light escape their incredible gravity, and that's why scientists need a certain kind of telescope that can identify the X-Rays on the fringes of the black hole, which will give them an idea of its size and rotation speed.

Part of the goal of the mission is to test Einstein's theory of general relativity, which set certain parameters for how fast he believed a black hole can spin.

Launch Preparation

Scott Barthelmy, a researcher at NASA's Goddard Space Flight Center in Greenbelt, Maryland, described the complicated pre-launch procedure needed to inflate the balloon and prep X-Calibur for flight.

The first step will be to roll out the ultra-thin plastic sheets of the balloon. Hoses will then pump pressurized helium into the balloon, which will expand and cause the balloon to rise in a mushroom-shaped cloud, until the 40-million-cubic foot (1,132,674 cubic meters) interior is full.

The ground weight will then be lifted off the balloon to let it rise. About 900 feet (274 m) of balloon material will be rolled out on the ground, and as the balloon rises it will pick up more and more of this train.

The very end of the balloon will be attached to X-Calibur.

A small crane will cradle X-Calibur about 10 feet (3 m) over the ground.

When the balloon drifts directly over the telescope and begins pulling up, a technician will be standing by to release the telescope from the crane.

If the release comes too early, the telescope could drop to the ground and smash. If it comes too late, the crane release could jam.

NASA's Columbia Scientific Balloon Facility website will host a live broadcast of the launch, which the scientists expect will happen around Sept. 14 or 15, if weather conditions allow. After the balloon launches, anyone can track its progress with a live Google map.