Axios

The globe's pronounced and unexpected temperature spike during the past few months is provoking unease among some of the most level-headed climate scientists.

The big picture: September was the most unusually warm month in recorded history. This followed record heat in June and July — which was also the planet's hottest month — as well as August.

The largest known solar storm struck Earth more than 14,000 years ago, according to a new study of the growth rings in ancient trees.

Why it matters: The discovery illustrates the immense power of solar storms — and underscores the danger they pose today.

The pristine sample of a 4.5 billion-year-old asteroid delivered to Earth last month contains water and high amounts of carbon, according to NASA.

Why it matters: That composition suggests life's building blocks may be found within the asteroid, the space agency said.