Five Things to Know About the 'Halloween Asteroid' https://gma.yahoo.com/5-things-know-halloween-asteroid-002900478--abc-news-Halloween.html [Broken] This asteroid was only discovered days ago. Coming within 1.3 lunar distances -- or ~310,000 miles (49000 km) -- the asteroid, called 2015 TB145 (width ~ 400 m), will brush past Earth but presents no threat to humans. NASA said this asteroid is incredibly fast and predicts it will zoom past Earth at 78,000 miles per hour (125500 kmph). http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2015 TB145;orb=1 The next close encounter of an object that size is expected to happen in in August 2027. That asteroid -- 1999 AN10 -- is estimated to be ~800 m and will brush by our planet at a distance of about 238,000 miles, according to NASA. Back in January 2015, NASA cited the following: But now we have a closer encounter with 2015 TB145. Some background: https://en.wikipedia.org/wiki/(137108)_1999_AN10 - one of many Apollo asteroids https://en.wikipedia.org/wiki/List_of_Apollo_asteroids As of 1 August 2015 NASA had listed a cumulative total of 1,605 discovered potentially hazardous asteroids (PHAs). Among these, there are 154 PHAs believed to be larger than one kilometer in diameter. https://en.wikipedia.org/wiki/Potentially_hazardous_object But not to worry, they've always been there.