Opponents of the Thirty Meter Telescope attack the telescope in any way possible. Any argument is fodder in social media and newspaper editorials. Many of these arguments depend on a superficial level of knowledge about astronomy, this claim is a good example of this.
The claim is that a ground based telescope like TMT is not needed as a space telescope is more capable. Why spend the money? Why build TMT on Mauna Kea?
Given the stunning accomplishments of the Hubble Space Telescope this sounds plausible. This argument also ignores a number of fundamental realities in telescope design and use. Both have their limitations and we will discuss some of the more important ones here.
Certainly a telescope in space has a number of advantages over a ground based telescope. Not having an atmosphere to look through helps, it helps a lot. This is countered by the way ground based telescopes have developed solutions to overcome those limitations. The limitations on a space telescope are not created by the atmosphere and as such are far more practical and daunting.
Continue reading “Space telescopes are better?”