The Hubble Space Telescope is back—for now. After a worrying month out of action because its payload computer failed, the problem has been fixed—and it’s begun doing science again already.
However, despite returning to action with some incredible shots of a pair of interacting galaxies there are warnings this week that its achievements could soon be replicated using … balloons.
Here’s everything you need to know about SuperBIT—the $5 million “floating telescope” whose wider angle lens and more megapixels will make it “better than Hubble.”
What is SuperBIT?
Described today at the online National Astronomy Meeting (NAM 2021), the Superpressure Balloon-borne Imaging Telescope (or SuperBIT) is a new kind of astronomical observatory—a low-cost balloon-borne telescope.
Due to debut next April 2022, SuperBIT will have a 0.5 metre diameter mirror and be carried 40km up to above 99.5% of the Earth’s atmosphere by a helium balloon the size of a football stadium.
“New balloon technology makes visiting space cheap, easy, and environmentally friendly,” said Mohamed Shaaban, a PhD student at the University of Toronto. “SuperBIT can be continually reconfigured and upgraded, but its first mission will watch the largest particle accelerators in the Universe: collisions between clusters of galaxies.”
For the first time NASA now has “superpressure” balloons that contain helium for months, well beyond the few days that was previously possible.
How can it be as good as Hubble?
Earth’s turbulent atmosphere blurs our view of the Universe. That’s why the biggest and best ground-based telescopes are built the top of high mountains where the atmosphere is at its thinnest. It’s also why our space telescopes have a clearer view—but it seems that getting above 99.5% of the Earth’s atmosphere is enough to get sharp images of the cosmos.
During a flight test flight in 2019, SuperBIT was able to remain stable for over an hour, which means its images should be as sharp as from any orbiting space telescope.
When will SuperBIT launch?
SuperBIT is scheduled to launch on a superpressure balloon in April 2022 from Wanaka, New Zealand.
During its flight it will circumnavigate the Earth, imaging the sky at night and recharging its batteries via solar panels during the day.
The advantages of balloon telescopes
Whereas space telescopes have to work first time and stay in space for decades—hence Hubble’s cameras being relatively low resolution—balloon telescopes like SuperBIT can be fixed and upgraded between flights.
SuperBIT’s 0.5 metre mirror could also soon be upgraded to 1.5 metres, which would make it better than Hubble … and in future it could even be one of a fleet of space telescopes.
Why we need a ‘new Hubble’
Although it was fixed in the 1990s and upgraded several times by astronauts on visiting Space Shuttles, Hubble cannot now be fixed. You might think that’s fine since NASA and ESA will soon launch the James Webb Space Telescope, but that monster space telescope images only at infrared wavelengths.
So when Hubble does die—and we’ve had a stark warning this month of just how quickly that could happen—astronomers won’t have an optical space telescope. If all goes well during its test flights, SuperBIT can fill the gap by offering high-resolution multicolour optical and ultraviolet observations well beynd the lifespan of Hubble.
What’s next for the Hubble Space Telescope
Meanwhile, it’s hoped that Hubble, which has made over 1.5 million observations of the cosmos in its 31 years, will now get the chance to work in tandem with the James Webb Space Telescope, which is due to launch in 100 days on October 31, 2021 (though that date could easily slip a week or two).
“I’m thrilled to see that Hubble has its eye back on the Universe, once again capturing the kind of images that have intrigued and inspired us for decades,” said NASA Administrator Bill Nelson. “This is a moment to celebrate the success of a team truly dedicated to the mission. Through their efforts, Hubble will continue its 32nd year of discovery, and we will continue to learn from the observatory’s transformational vision.”
Wishing you clear skies and wide eyes.