SN Online

EARTH
Scientists get closer to knowing the exact makeup of Earth’s innards. Read “Oxygen a bit player in Earth’s outer core.”

GENES & CELLS
A sense-mixing condition in which some people see smells or taste colors may have genetic roots. See “Unraveling synesthesia.”

BODY & BRAIN
An illusion that tricks people into thinking a sore hand is healthy can reduce pain. Learn more in “Mirrors can alleviate arthritis.”

An experimental therapy could improve heart attack treatment. See “Busting blood clots with a nano­particle.”