  X-ray astronomy is our gateway to the hot universe. More than half of the
baryons in the cosmos are too hot to be visible at shorter wavelengths.
Studying the extreme environments of black hole and neutron star vicinities
also requires X-ray observations. With the successful launch of ISRO's AstroSat
in 2015, and a few transformative results that emerged from JAXA's Hitomi
mission in 2016, a new window has been opened into high sensitivity fast timing
and high X-ray spectral resolution. Together with upcoming all-sky survey
missions expected very soon, X-ray astronomy is entering a new era of parameter
space exploration. The UK has been at the forefront of this field since the
1970s. But flat cash science budgets, compounded with the rising costs of
cutting-edge space missions, imply inevitably diminishing roles for the UK in
terms of both payload development and science exploitation in the future. To
review the novel science possibilities enabled by recent and upcoming missions,
and to discuss how to pave the way forward for X-ray astronomy in the UK, a
specialist RAS discussion meeting was held in London on Feb 10 2017, summarised
herein. A consolidated effort by the community to come together and work
cohesively is a suggested natural first step in the current climate.
