The atmosphere of the Archean eon—one-third of Earth's history—is important for
understanding the evolution of our planet and Earth-like exoplanets. New geological proxies …

The Sun and other stars are magnetic: magnetism pervades their interiors and affects their
evolution in a variety of ways. In the Sun, both the fields themselves and their influence on …

The nature of the early martian climate is one of the major unanswered questions of
planetary science. Key challenges remain, but a new wave of orbital and in situ observations …

Reconciling the geology of Mars with models of atmospheric evolution remains a major
challenge. Martian geology is characterized by past evidence for episodic surface liquid …

On the basis of geological evidence, it is often stated that the early martian climate was
warm enough for liquid water to flow on the surface thanks to the greenhouse effect of a thick …

For more than four decades, scientists have been trying to find an answer to one of the most
fundamental questions in paleoclimatology, the “faint young Sun problem.” For the early …

We use a 3‐D general circulation model to compare the primitive Martian hydrological cycle
in “warm and wet” and “cold and icy” scenarios. In the warm and wet scenario, an …

The Sun's magnetic activity has steadily declined during its main-sequence life. While the
solar photospheric luminosity was about 30% lower 4.6 Gyr ago when the Sun arrived on …

We explore the ramification of associating the energetics of extreme magnetic reconnection
events with transient mass-loss in a stellar analogy with solar eruptive events. We establish …

The Sun provides a critical benchmark for the general study of stellar structure and
evolution. Also, knowledge about the internal properties of the Sun is important for the …