When Greenland was green, bear back-scratching, Mars voyage emotional toll, fin whale seismic sensing, what made COVID-19 vaccines possible and gas fume shadows
Ice cores drilled for missile silo research reveals when Greenland was last green; Grizzly Tinder: Bears rubbing up against trees may be their dating calling card; Microgravity on a trip to Mars might leave astronauts emotionally impaired; Listening in on fin whale calls to do seismic sensing of the ocean floor; COVID vaccines were made in record time. Meet a scientist who made that possible; Why do gasoline fumes cast a shadow on a cold, sunny day?