Science News drew over 21 million visitors to our website this year. Here’s a rundown of the most-read news stories and long reads of 2021.
Instruments on the International Space Station detected the origins of an odd type of lightning called a blue jet. The bizarre bolt is sparked by a “blue bang” — a flash of bright blue light that may be brought on by the turbulent mixing of oppositely charged regions within a thundercloud (SN: 2/13/21, p. 14).
The first atomic bomb test, in 1945, forged a peculiar, glassy material called trinitite — and within it, a rare form of matter called a quasicrystal. Quasicrystals’ atoms are arranged in an orderly structure like normal crystals, but the structure’s pattern doesn’t repeat (SN: 6/19/21, p. 12).
The Ayta Magbukon people in the Philippines set the record for the highest known level of Denisovan ancestry — about 5 percent of their DNA comes from the ancient hominids. The finding suggests that several Denisovan populations independently reached Southeast Asia and interbred with Homo sapiens groups that arrived thousands of years later (SN: 9/11/21, p. 16).
In a first, astronomers caught a glimpse of a rare double cosmic cannibalism: A star swallowed a black hole or neutron star, which then gobbled that star from within, resulting in an astonishing explosion (SN: 10/9/21 & 10/23/21, p. 6).
Skin stem cells plucked from frog embryos organized themselves into miniature living robots, dubbed “xenobots,” that can swim, move around debris and even self-heal. Xenobots may one day serve a useful purpose, but ethical questions need to be considered (SN: 4/24/21, p. 8).
Acrobatic rabbits bewitched online readers in our most-viewed YouTube video posted this year. The video — accompanying the story “A gene defect may make rabbits do handstands instead of hop” (SN: 4/24/21, p. 13) — shows a sauteur d’Alfort rabbit walking on its front paws (below). Such hop-less bunnies may have adopted the odd gait because of a mutation in a gene called RORB, scientists discovered.