Science News Roundup: Why did menopause evolve? New study of whales gives some clues; Japanese firm Space One's Kairos rocket explodes on inaugural flight

New research examines menopause in these whales, with findings that may help explain why this phenomenon evolved, given that it is known in just six of the 6,000-plus mammal species living today.

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Why did menopause evolve? New study of whales gives some clues

Menopause is a rare trait among Earth's species, known to exist in only a few. Humans are one. Killer whales and four other toothed whales are the others. New research examines menopause in these whales, with findings that may help explain why this phenomenon evolved, given that it is known in just six of the 6,000-plus mammal species living today. It might be titled: the tale of the helpful grandma whale.

Japanese firm Space One's Kairos rocket explodes on inaugural flight

Kairos, a small, solid-fuel rocket made by Japan's Space One, exploded just seconds into its inaugural launch on Wednesday as the firm tried to become the first Japanese company to put a satellite in orbit. The setback for Space One and the rocket industry in Japan comes as the government and investors ramp up support for the sector amid a national security buildup and skyrocketing demand for commercial satellites.

(With inputs from agencies.)