Uncategorized

  1. Physics

    CO2 from champagne bottles can form shock waves like those seen in rocket exhaust

    Popping a bottle of bubbly releases a plume of dry ice that bears a visible type of shock wave called a Mach disk.

    By Maria Temming
  2. Physics

    Can time travel survive a theory of everything?

    It’s not yet clear whether a theory that unites general relativity and quantum mechanics would permit time travel.

    By Tom Siegfried
  3. Plants

    Why tumbleweeds may be more science fiction than Old West

    A tumbleweed is just a maternal plant corpse giving her living seeds a chance at a good life somewhere new.

    By Susan Milius
  4. Life

    We’ve lost 3 billion birds since 1970 in North America

    Scientists estimated the change in total number of individual birds since 1970.