How long you can survive in space without spacesuite

A primordial flash

The primordial universe continues to reveal its mysteries to us: a research group led by Christina Williams from the Steward Observatory of the University of the Arizona, using the 66 antennas that constitute the ALMA radiotelescope in Chile, has revealed a weak emission in radio frequencies, probably dued to the dust generated by stellar formation inside a giant primordial galaxy, about 12.5 billion years away from us, just more than a billion year after the initial expansion of the spacetime (the Big Bang).

Williams, C. C., Labbe, I., Spilker, J., Stefanon, M., Leja, J., Whitaker, K., ... & Weiner, B. (2019). Discovery of a Dark, Massive, ALMA-only Galaxy at z∼ 5–6 in a Tiny 3 mm Survey. The Astrophysical Journal, 884(2), 154. doi:10.3847/1538-4357/ab44aa (arXiv)

We know we don't know

A few days ago on Nature Astronomy it was published a paper by a team of italian researchers with an unequivocal title: Planck evidence for closed Universe and a possible crisis for cosmology⁽⁶⁾. We can consider it as one of the first scientific articles that seriously takes into consideration a situation that it is becoming increasingly pressing: a crisis in cosmology.
The standard cosmological model, based on cosmic inflation⁽²⁾ and on empirical constants that evaluate unknown physical quantities as dark matter and dark energy, although very well verified, has not yet passed the last step: the detection of gravitational waves in cosmic microwave background (CMB). One of the fundamental points of this model, but also of many of the surviving competing models, is the accelerated expansion of spacetime at speed greater than that of light which explains the flatness of the early universe.
This flatness emerges in particular when studying the cosmic microwave background, the residual energy of the initial expansion of spacetime. This radiation has come down to us from the point where it was produced, a little less than 14 billion years ago, crossing the whole universe. This means that in the signal detected there must also be gravitational lens effects⁽¹⁾ due to the amount of matter, usual and dark, present in the universe. These effects have long been known and calculated⁽⁴⁾ and can already be seen in the image produced by Planck⁽⁵⁾.