163 citations · 163 across the 1 of their papers we have counts for
Showing astro-phShow all
2 papers · 1 filter
astro-ph2007★ 163 cited
Habitat of early life: Solar X-ray and UV radiation at Earth's surface 4-3.5 billion years ago
I. Cnossen, J. Sanz-Forcada, F. Favata +3
Solar X-ray and UV radiation (0.1-320 nm) received at Earth's surface is an important aspect of the circumstances under which life formed on Earth. The quantity that is received de…
astro-ph1998
Hubble constant from sosie galaxies and HIPPARCOS geometrical calibration
G. Paturel, P. Lanoix, P. Teerikorpi +5
New distances, larger than previous ones, have been obtained for M 31 and M 81 based on the geometrical zero-point of the Cepheid Period-luminosity relation provided by the HIPPARC…