Cara Lucy O'Connor, a 6-year-old Irish student, wrote to NASA to "make Pluto a planet again", saying it's unfair that Pluto isn't a planet. "It's not...about whether Pluto is a dwarf...it's that Pluto is a fascinating place", NASA replied. She added she hopes to discover her own planet, call it Planet Unicorn and visit all main planets including Pluto.