Billion-dollar telescopes could end up beyond the reach of US astronomers
International competition is growing. The European Space Agency has picked its key projects as far ahead as 2044, including an advanced X-ray space observatory. The European Southern Observatory has fully funded its Extremely Large Telescope (ELT) in Chile. From the mid-2020s, its 39-metre-diameter mirror will collect more than ten times as much light as the largest optical telescopes today. China opened the world’s biggest radio telescope in Guizhou province in 2016, and plans to launch a competitor to the Hubble Space Telescope4.
Without a concerted effort, a US scientist in the 2030s will be left without similarly capable facilities. We will face an unacceptable dilemma: support existing grants and cede US leadership, or abandon funding for key areas of research to support a few world-leading facilities.
As the presidents of organizations that build and operate major US publicly funded telescopes on behalf of the NSF and NASA, here we set out how entrenched assumptions and patterns of funding, development and collaboration must be reassessed.
Federal support essential
The United States has historically built its strength in astronomy on an eclectic mix of private and public observatories. Early telescopes such as those at the Mount Wilson, Griffith and Lick observatories in California were funded by foundations and run by universities. Edwin Hubble discovered the expansion of the Universe at Mount Wilson in the 1920s, for example. Until 2009, the United States hosted the world’s largest telescopes: the twin W. M. Keck telescopes in Hawaii each have mirrors 10 m across and were paid for largely by philanthropy. (That accolade is now held by the 10.4-m Gran Telescopio Canarias in the Canary Islands, Spain.)
After the Second World War, the US federal government set up national observatories for radio and optical astronomy. The rationale was to boost national and economic security by investing in basic science. On the ground, this has led the NSF to establish major facilities such as the Very Large Array in New Mexico, the Gemini Telescopes in Hawaii and Chile, and, most recently, ALMA. In space, NASA runs iconic observatories such as the Hubble and Spitzer space telescopes and the Chandra X-Ray telescope. US astronomers from any institution compete through a peer-review process for time on telescopes.
This mixed system has worked well for decades. But the next generation of ground-based telescopes has become so expensive that even consortia of universities and institutes are struggling, despite hefty contributions from billionaires, state governments and international partners.
US-led efforts to construct giant telescopes to match the European ELT plans have stalled. Both the Giant Magellan Telescope (GMT), a 25-metre-mirror telescope under construction in Chile, and the Thirty Meter Telescope (TMT), which it is hoped will be built on Mauna Kea in Hawaii, have been unable to find the billion dollars or more that each will need. In May, the two teams joined forces and announced they would seek extra NSF funding through the Decadal Survey5. In return, they will enable broad US community access to the two telescopes, providing coverage of both hemispheres of the night sky.
Big science perceptions
Space astronomy has always been federally supported, and is expensive. The total bill of the JWST has mounted to more than US$9 billion, not helped by a series of delays. The proposed Wide-Field Infrared Survey Telescope (WFIRST), which will examine exoplanets and dark energy should it launch in the late 2020s, would cost at least $3 billion.
Both projects have come under fire for their costs. In February, US President Donald Trump proposed cancelling WFIRST, although Congress subsequently approved funding for it. Incoming NASA administrator Jim Bridenstine has queried the need for any large science missions. He said in May6: “If we can do smaller missions with multiple satellites, then any one of them that runs over doesn’t clobber the decadal [survey] not only for this decade but also the next decade”.
Yet if inflation is taken into account, the cost of the JWST is comparable with that of the Hubble telescope: $3 billion in 1990 translates to around $9 billion today (see ‘Astronomical costs’, middle right panel). Even in its peak fun
Publisher URL: https://www.nature.com/articles/d41586-018-05985-2
Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.
Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.