The Newly Proposed High Definition Space Telescope Makes Hubble Look Like a Toy

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The James Webb Space Telescope (JWST), which will be “in many ways a hundred times” more capable than Hubble, isn’t launching until 2018, but already astrophysicists are thinking about its successor. They’re calling it the High Definition Space Telescope (HDST). That’s it on the far right, towering over both its predecessors.

Here’s Ramin Skibba reporting for Universe Today:

As the HDST’s name suggests, its 12-meter wide segmented mirror would give it much higher resolution than any current or upcoming telescopes, allowing astronomers to focus on many Earth-like “exoplanets” orbiting stars outside our solar system up to 100 light-years away, resolve stars even in the Andromeda Galaxy, and image faraway galaxies dating back 10 billion years of cosmic time into our universe’s past. The 24x increased sharpness compared to Hubble and the upcoming James Webb Space Telescope is similar to the dramatic improvement of an UltraHD TV over a standard television, according to Marc Postman, an astronomer at the Space Telescope Science Institute.

In particular, “exoplanets are the main science driver for the HDST,” said [MIT astrophysicist Sara Seager]. “Are there other planets like Earth, and are there signs of life on them?” Her and her colleagues’ excitement came through as she explained that, if the telescope comes to fruition, they predict it would find dozens, if not hundreds, of Earth-like planets in the habitable zone. They would look for evidence of oxygen and water vapor as well, transforming astronomers’ knowledge of such planets, currently limited to only 1 or 2 candidates detected by the Kepler telescope.


The Association of Universities for Research in Astronomy (AURA) presented its proposal for the HDST in a report issued last month. An excerpt from the website established by the association encapsulates the vision for the project:

HDST has the potential to push back the frontiers of astrophysics with a single great observatory. Rather than small focused missions that have a shot at finding one to a few exoEarths (while relying on unusually good fortune to turn up signs of life on even one), or that specialize in a particular subfield of astrophysics, HDST pursues the more ambitious approach. HDST’s sensitivity, resolution, and efficiency of exoplanet characterization make it a profoundly capable mission. It can deliver a high yield of exoEarths along with a rich database of information about all kinds of planetary systems. At the same time, and often while observing in tandem with exoEarth searches, HDST will fundamentally change our understanding of the Universe throughout cosmic time. Many fields of astronomy will be transformed by its capabilities; none will remain entirely untouched. HDST will transform how we all—scientists and public alike—see our place in the universe.


Development started on JWST immediately after Hubble launched. Pending funding, development of the HDST would probably follow a similar timeline, with design and construction happening throughout the 2020s and a launch happening in the 2030s.

[AURA via Universe Today]

Contact the author at Top image: “A direct, to-scale, comparison between the primary mirrors of Hubble, JWST, and HDST. In this concept, the HDST primary is composed of 36 1.7 m segments. Smaller segments could also be used. An 11 m class aperture could be made from 54 1.3 m segments” via the AURA report. Rob Bricken made me add the ghost lady, who appears in other comparisons between Hubble and JWST, for scale.