sending a telescope into space with a helium balloon
Scientists have decided to find an innovative, cheaper and more flexible way to launch something into space and are experimenting with using helium balloons instead of rocket technology when sending telescopes.
source
They left the rockets
Universities in Durham, Toronto, and Princeton have teamed up with NASA and the Canadian Space Agency (CSA) to develop a new astronomical telescope. The Super Pressure Balloon-Based Imaging Telescope, called SuperBIT, travels through the Earth's atmosphere in a helium balloon with a volume of 532,000 cubic meters. The balloon is almost the size of a stadium.
In a press release at the National Astronomy Meeting, scientists hope to get images as sharp as those from the Hubble Space Telescope with the telescope to be sent in this way.