| Clue | Source | Date |
|---|---|---|
| The Karman line, which is 100,000 meters from Earth's surface, is generally accepted as the starting point for this activity | ||
| Pitches flag badly, on trip devoid of atmosphere (5,6) | ||
| Second step following delicate venture for astronauts? (5,6) | ||
| *NASA event | The Washington Post | 05 May 2021 |
| *NASA event | LA Times Daily | 05 May 2021 |
| Opening stairs for approach to higher regions? | ||
| A Big Apple newspaper called it ''impossible'' in 1920 | Newsday | 05 Jan 2020 |