| A | B |
|---|
| launched | started in motion or sent off |
| particles | small bits or pieces of an element |
| dense | thick or packed closely together |
| inflate | to cause to swell by filling with air or gas |
| anchored | held firmly in place |
| companion | a person or animal who keeps somebody company |
| hydrogen | a light gas that burns easily |
| jostling | pushing and shoving |
| menagerie | a collection of various animals |
| perplexing | puzzling or confusing |
| scientific | having to do with or used in science |
