An artist rendering of the Thirty Meter Telescope, planned for construction on Maunakea in Hawaii.Credit: TMT International Observatory/Courtesy of NAOJ with the cooperation of Mitsubishi Electric (CC BY 4.0) They have been planning for years to build the Giant Magellan Telescope on a mountaintop in Chile, and the Thirty Meter Telescope on the Hawaiian mountain Maunakea. Construction has started in Chile, while the Thirty Meter project has been building telescope components and doing other off-site work owing to concerns from Native Hawaiians over Maunakea, which they consider sacred. Both projects are backed by international groups of funders, but neither has the estimated US$3 billion needed to fully fund its telescope. Many astronomers had hoped that the US National Science Foundation (NSF) would contribute money to cover the funding shortfall. But last week the National Science Board, which oversees the NSF, recommended that the agency cap its giant-telescope contributions at $1.6 billion. The board also signalled that it was reluctant for the NSF to spend even that much, citing the need to build other facilities 'across a wide range of science and engineering fields'....

With the increasing interest in lunar exploration, an astrobiologist explores how further access to Earth's natural satellite could help humanity and science....

For radioastronomers, the far side of the Moon could be the last unspoilt refuge in the Solar System. Planet Earth ' and all the human-made electromagnetic noise it spews out into space ' stays permanently below the horizon, so that any radio observatories positioned there would be free to observe the cosmos without interference. But an upcoming boom in lunar exploration could put that at risk. In the next ten years or so, the Moon will be the target of hundreds of orbiters and landers, each of which could create radio noise. Researchers voiced their concerns last month at a conference called Astronomy from the Moon: The Next Decades, which took place at the Royal Society in London. 'Will the far side remain dark' You should already be nervous that I'm asking the question,' Joseph Lazio, a researcher at NASA's Jet Propulsion Laboratory in Pasadena, California, told the conference. The lunar far side has enormous potential for many fields, but it holds unique promise for cosmology. Astronomers have mapped the sky using much of the spectrum of electromagnetic waves, from microwaves to visible light and '-rays. But cosmic radio waves at frequencies below about 100 megahertz are extremely challenging to measure from Earth, because of the planet's noise. And anything below 30 megahertz is completely off-limits because it is absorbed in the ionosphere ' the zone where Earth's atmosphere meets space. These low-frequency waves, however, carry a treasure trove of information about the first billion years or so of the Universe's history....

It takes expensive tools to learn about the universe, but projects like the Very Large Array for radio astronomy in New Mexico and the Chandra X-ray Observatory, which orbits Earth, have pushed scientific knowledge forward in ways that would not have been possible without these instruments. Every 10 years, astronomers and astrophysicists outline priorities for the hardware they need in the decadal survey on astronomy and astrophysics. The newest version of the survey was published by the National Academies of Sciences, Engineering and Medicine in late 2021, and debates about funding are in full swing for the next fiscal year. I'm a professor of astronomy whose research has depended on facilities and equipment built after a recommendation in one of these decadal surveys, and I was involved in the previous survey, published in 2010. The decadal survey of astronomers is influential because it forces everyone to be on the same page and make hard choices. It has to temper ambition with realism, but when astronomers and astrophysicists from the many subfields all work together, they come up with ideas that advance the whole field....