• The extent to which astrophysical neutrinos can help us address open questions in fundamental neutrino physics, such as the absolute scale of neutrino mass and the hierarchy, on a timescale comparable to that envisioned for major terrestrial experiments, such as LBNF and LBNO.

• The new opportunities that arise for using neutrinos to probe astrophysical objects – such as the Sun, supernovae, and high-energy astrophysical accelerators – given that we now know enough about their properties to interpret neutrino signals.

• The role of neutrinos in controlling the conditions important for nucleosynthesis in astrophysical environments such as the Big Bang, supernovae, and accretion disks.

• The prospect for constraints or signals of neutrino mass and number from cosmological data, including the cosmic microwave background and large scale structure.

These themes are timely in view of recent experimental progress in neutrino physics, such as the results from IceCube, Planck and GERDA. The program aims at involving theorists, experimentalists and observers, with an effort to engage many of the younger scientists working in this subfield.

The proposed format is of three weeks of regular program, with morning seminars and afternoon informal discussions, and a one-week workshop (June 15 - 19, 2015) as a catalyzer. Ample time will be given to postdocs and advanced graduate students to present their work, with preference to particularly innovative ideas. There is a registration fee of $40 to attend this workshop. You may pay in cash -- exact change preferred -- or by a check drawn on a U.S. bank.