The Hubble space telescope has enabled remarkable advancements in astronomy over the last 25 years, far more than paying back the few billion it cost to build and maintain the system. That said, new technologies are enabling the construction of greatly improved space telescopes. Some astronomers, including Hubble researchers, believe that future generations of space telescopes will give us a much better chance to finally settle the question of alien life.
More on the Hubble Space Telescope
The Hubble space telescope was a joint project of NASA and the European Space Agency, and was launched on the space shuttle Discovery on April 24th, 1990. Of interest, astronauts had to take a spacewalk to fix a major problem with the telescope back in 1993, but since then, Hubble has been expanding astronomers knowledge and and bringing gorgeous pictures of the cosmos within reach of virtually everyone on the planet.
“The Hubble has really allowed people to participate in the excitement of discovery,” noted Mario Livio, an astrophysicist at the Space Telescope Science Institute in Baltimore, which manages the Hubble’s science program. “Hubble images have become part of our culture,” Livio told Space.com. “I regard this as an incredible contribution.”
Giant space telescopes
Livio says a third-fourth generation Hubble space telescope would allow scientists to be much more accurate in their search for alien life. He notes that with a primary mirror at least 39 feet (12 meters) wide, the new telescope could produce images 25 times sharper than the Hubble. For perspective, the current main mirrors of Hubble are just 7.9 feet [2.4 meters], 7.9 feet and 21.3 feet [6.5 meters] wide.
This new device would be able to scan enough Earthlike planets in other solar systems at a great enough level of detail that “meaningful statistical constraints” on the relative rarity of alien life in the galaxy could be determined, according to Livio.
“A large sample of planets — around 50 — would have to be tested,” he noted in his recent Nature commentary. “Calculations show, for example, that if no biosignatures are detected in more than about three dozen Earth analogues, the probability of remotely detectable extrasolar life in our galactic neighborhood is less than about 10 percent.”