  We investigate global well-posedness to the Cauchy problem of
three-dimensional compressible viscous and heat-conducting micropolar fluid
equations with zero density at infinity. By delicate energy estimates, we
establish global existence and uniqueness of strong solutions under some
smallness condition depending only on the parameters appeared in the system and
the initial mass. In particular, the initial mass can be arbitrarily large.
This improves our previous work [23]. Moreover, we also generalize the result
[13] to the case that vacuum is allowed at infinity.
