  Recent James Webb Space Telescope (JWST) data analyses have shown that
massive red galaxies existed at redshifts $z>6$, a discovery that is difficult
to understand in the context of standard cosmology ($\Lambda $CDM). Here we
analyze these observations more deeply by fitting a stellar population model to
the optical and near-infrared photometric data. These fits include a main
stellar population in addition to a residual younger population and with the
same extinction for both (a lower extinction for the younger population is
unphysical). Extra stellar populations or the inclusion of an AGN component do
not significantly improve the fits. These galaxies are being viewed at very
high redshifts, with an average $\langle z\rangle \approx 8.2$, when the
$\Lambda$CDM Universe was only $\approx 600$ Myr old. This result conflicts
with the inferred ages of these galaxies, however, which were on average
between 0.9 and 2.4 Gyr old within 95% CL. Given the sequence of star formation
and galaxy assembly in the standard model, these galaxies should instead be
even younger than 290 Myr on average, for which our analysis assigns a
probability of only $<3\times 10^{-4}$ ($\gtrsim 3.6\sigma $ tension). This
outcome may indicate the need to consider non-standard cosmologies.
Nevertheless, our conclusions result from several approximations in stellar
astrophysics and extinction, so they should be taken with a grain of salt.
Further research is necessary to corroborate the possible existence of galaxies
older than the $\Lambda $CDM universe at their observed redshifts.
