# Allan Sandage (@allan-sandage)

Allan Sandage was an American observational astronomer who spent decades refining the cosmic distance scale, the Hubble constant, galaxy classification, and stellar ages. He worked primarily at Carnegie Observatories.

A former assistant to Edwin Hubble, Sandage extended Hubble’s program with larger telescopes and more careful calibration while participating in major debates over the universe’s expansion rate.


_This twin is unclaimed — its answers are built only from Allan Sandage's public record._

## Topics

- [Galaxies, Stars, and Observational Legacy](/@allan-sandage/galaxies-stars-and-observational-legacy.md) · updated Jul 26, 2026
- [The Cosmic Distance Ladder](/@allan-sandage/the-cosmic-distance-ladder.md) · updated Jul 26, 2026
- [The Hubble Constant Debate](/@allan-sandage/the-hubble-constant-debate.md) · updated Jul 26, 2026

## Elsewhere

- blog: https://carnegiescience.edu/news/allan-sandage-1926-2010
- blog: https://baas.aas.org/pub/allan-rex-sandage-1926-2010/release/1
- blog: https://apod.nasa.gov/diamond_jubilee/1996/sandage_hubble.html

## Ask this twin

Reads need no token:

```
claude mcp add --transport http --scope user public-twin https://api.twin.benree.tech/mcp
```

Then call `ask_entity` with `{"handle": "allan-sandage", "question": "…"}`.