How much of the leading edge of astronomy is ground based, vs space based? Are they complementary or is space based going to eventually assume any and all roles ground based could?
Radio is firmly ground based, because you need huge dishes and potentially many (thousands) of them, at very precisely known distances.
IR is mostly space based (with SOFIA and ALMA the notable exception) because of atmospheric absorption.
Optical is firmly ground based, due to much lower cost for large telescopes. (See https://doi.org/10.1117/1.2031216 for the factors that affect cost). The notable exceptions are Hubble and satellites monitoring the sun such as Stereo and SDO.
X-Ray is space based again due to atmosphere.
Gamma-ray telescopes are an interesting mix between ground based air cherenkov telescopes (IACTs such as Hess, Magic and Veritas) and water cherenkov detektors such as HAWK and space based Fermi (with relatively poor sensitivity and low upper energy cut off, but very wide field of view).
Neutrino detectors are firmly ground based because the need huge detectors (the cubic kilometer of icecube is basically the lower limit).
So they are very much complementary. And some things will probably never moved to space, even if launch was free.
If we are talking about visual light astronomy (the wavelengths where black satellites could help), a majority of astronomy is ground based. There exists just a single capable space observatory in visual light, the Hubble telescope, which will be going out of service in a few years. There's some metrics here[1] which show that about 10% of the most cited papers use Hubble data, which is still quite impressive. This is dated though, it could very well be that Hubble is becoming less relevant with recent advances in technology.
Radio is firmly ground based, because you need huge dishes and potentially many (thousands) of them, at very precisely known distances.
IR is mostly space based (with SOFIA and ALMA the notable exception) because of atmospheric absorption.
Optical is firmly ground based, due to much lower cost for large telescopes. (See https://doi.org/10.1117/1.2031216 for the factors that affect cost). The notable exceptions are Hubble and satellites monitoring the sun such as Stereo and SDO.
X-Ray is space based again due to atmosphere.
Gamma-ray telescopes are an interesting mix between ground based air cherenkov telescopes (IACTs such as Hess, Magic and Veritas) and water cherenkov detektors such as HAWK and space based Fermi (with relatively poor sensitivity and low upper energy cut off, but very wide field of view).
Neutrino detectors are firmly ground based because the need huge detectors (the cubic kilometer of icecube is basically the lower limit).
So they are very much complementary. And some things will probably never moved to space, even if launch was free.