Based on recent progress in quantum gravity and quantum cosmology we are presenting also a way to estimate the temperature in cosmos, the Hubble sphere, from a relation between the Planck temperature and the Hubble scale. Our analysize predict the Hubble sphere temperature of 2.72k with the one standard deviation confidence interval between 2.65k and 2.80k, which correspond well with the measured temperature observed from the cosmic microwave background (CMB) of about 2.72k. This add evidence to that there is a close connection between the Planck scale, gravity and the cosmological scales as anticipated by Eddington already in 1918.