Which of the following is/are cited by the scientists as evidence/evidences for the continued expansion of universe?

1. Detection of microwaves in space — Correct. The cosmic microwave background radiation is a major observational evidence supporting the Big Bang model and the expanding universe.
2. Observation of redshift phenomenon in space — Correct. Redshift of distant galaxies shows they are moving away, which is direct evidence of expansion of the universe.
3. Movement of asteroids in space — Incorrect. Asteroid motion is governed by local gravitational dynamics within solar systems, not evidence for cosmic expansion.
4. Occurrence of supernova explosion in space — Incorrect. Supernovae are stellar events; while some distant Type Ia supernova observations helped study acceleration, the mere occurrence of supernova explosions is not itself cited as basic evidence of continued expansion.

Hence, statements 1 and 2 only are correct.