For many years, astronomers have looked forward to a coming revolution in ground-based astronomy: going from the current generation of 8-to-10 meter telescopes to the next generation of 30-meter class telescopes. Approximately a decade ago, a variety of partnerships selected their preferred sites, instruments to build, and facilities to construct. Now, in 2019, two of them are right on track, while one — the Thirty Meter Telescope (TMT) in Hawaii — is years behind.
The overwhelming majority of astronomers recognize that the preferred site for TMT, atop Hawaii’s Mauna Kea, would be the technically superior location to build it. But doing so would ignore the objections of many citizens whose concerns and values have been marginalized for over a century. As astronomers prepare for a field-defining choice, here’s what everyone should know.