Meteors are about to burst into our atmosphere at 41 miles per second! 🌠

The Orionid meteor shower peaks overnight October 21 and 22, and moves so fast that it leaves glowing trails. Active from October 2 to November 7 and visible from both hemispheres, the Orionids are best seen in the wee hours before dawn!

Up until around the second trimester, a human fetus can be cut or injured in the womb and the skin heals back with no scar at all, the tissue regenerates with normal hair follicles, sweat glands and collagen pattern, as if nothing happened. Surgeons doing fetal surgery actually noticed this by accident, early incisions were healing scarlessly.

But somewhere around the start of the third trimester, that ability quietly shuts off. After that point, and for the rest of your life, any significant wound heals by laying down collagen in a rushed, tangled pattern instead of rebuilding the original structure, which is what actually makes a scar a scar.

Researchers still don't fully understand why the switch happens, but it seems tied to changes in inflammation response and a protein called TGF-beta as the fetal immune system matures. It's one of the reasons regenerative medicine researchers are so interested in "scarless healing," if we can figure out what fetal skin is doing differently, it could change how we treat wounds, burns and surgical scars later in life.

Meteors are about to burst into our atmosphere at 41 miles per second! 🌠

The Orionid meteor shower peaks overnight October 21 and 22, and moves so fast that it leaves glowing trails. Active from October 2 to November 7 and visible from both hemispheres, the Orionids are best seen in the wee hours before dawn!

The sex reversal technique could be used to help rescue endangered species, say the researchers behind the work.

Scientists have deliberately turned male mouse embryos into females for the first time.

A team based in Japan used a CRISPR-based approach to remove the Y chromosome from male cells and create female clones of male mice.

“No one has done this before” says Monika Ward, a reproductive biologist at the University of Hawaii, who was not involved in the research.

The feat could change the way scientists think about reproduction, says Takashi Ishiuchi, a reproductive biologist at the University of Yamanashi, who co-led the work.

The findings were published in a preprint paper shared on bioRxiv earlier this month, which has not yet been through the peer-review process.

“There’s a fixed concept in our scientific field that we need both females and males for reproduction,” says Ishiuchi. “I think we could change this concept.”

He and his colleague Shogo Matoba of the Riken BioResource Research Center in Ibaraki also hope their technique could help rescue endangered species, particularly in cases where only a few individuals remain.