○○○ nebula ⪢⪢
The
solar system came into being about 4.5 billion years ago when a cloud of interstellar gas and dust collapsed resulting in a
solar nebula, a swirling disk of material that collided to form the
solar system.
http://qindex.info/i.php?x=11710
○○○ Pluto ⪢⪢
When _____ was discovered in 1930, it was named the 9th planet of the
solar system. More than 75 years later, that planetary status revoked and _____ was demoted to a dwarf planet.
￫ revoke, demote #Greece
http://qindex.info/i.php?x=11711
○○○ drift ⪢⪢
More than that, the sun is what holds the
solar system together. It's massive gravity is what keeps the earth and all the other planets circling around it instead of drifting off into space.
http://qindex.info/i.php?x=19742
• Present Perfect
Scientists say they have found evidence of a giant planet in the
solar system. There have only been two true planets discovered since ancient times. Planets have been predicted before and then were not found.
http://qindex.info/i.php?x=4149
