# Quasi-Stellar (DD-106)

> A quasar is an extremely luminous active galactic nucleus: a supermassive black hole at the center of a galaxy surrounded by a gaseous accretion disk. As gas falls toward the black hole it heats up and releases enormous energy across the electromagnetic spectrum, often outshining the host galaxy. The name comes from 'quasi-stellar radio source', because the first ones found in the 1950s and 60s looked like faint stars. Maarten Schmidt identified the redshift of quasar 3C 273 in 1963, showing quasars are very distant. The footage shows renderings of galaxies, accretion disks and black holes.

- Department: Space (also Science)
- First published: 2023-12-04
- Last updated: 2023-12-04
- Permalink: https://detailenjoyer.com/case/quasi-stellar/
- Author: Marcus Easterling (DetailEnjoyer), The Detail Department

## On the timeline

- **1963**: Maarten Schmidt identifies the redshift of 3C 273

Full timeline: https://detailenjoyer.com/timeline/?case=quasi-stellar

## Quick facts

- **DD-106-F01**: Quasars are luminous active galactic nuclei. _(Write-up · Exhibit A (Active nuclei))_
- **DD-106-F02**: They're powered by supermassive black holes. _(Write-up · Exhibit B (Black holes))_

## Write-up

Some of the brightest objects in the universe are feeding black holes. Quasar is short for quasi-stellar radio source.

1. **Active nuclei**: Quasars are luminous active galactic nuclei.
2. **Black holes**: They're powered by supermassive black holes.
3. **Accretion disks**: Infalling gas in an accretion disk releases energy.
4. **The name**: 'Quasar' comes from quasi-stellar radio source.
5. **3C 273**: Schmidt measured 3C 273's redshift in 1963.

## Related case files

- [Solar Prominence (DD-038)](https://detailenjoyer.com/case/solar-prominence/): I paired it with energy from our own star
- [Disk Jets (DD-495)](https://detailenjoyer.com/case/disk-jets/): I linked more on quasars

## Reel vs. record

- **Note**: None needed.

## Video: Quasi-Stellar: Some of the Brightest Objects in the Universe Are Feeding Black Holes

- Duration: 33.3 s · Published: 2023-12-04
- File: https://detailenjoyer.com/assets/videos/C0b-JyMuBUj.mp4

### Transcript

Quasars are extremely luminous and energetic objects found at the centers of distant galaxies. DID YOU KNOW? The term quasars stands for Quasi-Stellar Radio Source, reflecting their star like appearance when observed through early telescopes. Despite their appearance, quasars are not stars but rather active galactic nuclei powered by supermassive black holes. The intense energy emitted by quasars is generated as matter spirals into the black hole forming an accretion disk. This process releases tremendous amounts of energy across the electromagnetic spectrum making quasars some of the brightest and most distant objects observed in the universe. NOW YOU KNOW!

## Questions & answers

**Q: What powers a quasar?**  
A: Via its accretion disk. _(Source: Write-up · Exhibit A (Active nuclei) · Wikipedia: Quasar)_

**Q: Where are quasars found?**  
A: Active galactic nuclei. _(Source: Write-up · Exhibit B (Black holes) · Wikipedia: Quasar)_

**Q: What forms around the black hole?**  
A: Gas heats as it falls. _(Source: Write-up · Exhibit C (Accretion disks) · Wikipedia: Quasar)_

**Q: What does 'quasar' stand for?**  
A: They looked like stars. _(Source: Write-up · Exhibit D (The name) · Wikipedia: Quasar)_

**Q: Which quasar's redshift was measured in 1963?**  
A: By Maarten Schmidt. _(Source: Write-up · Exhibit E (3C 273) · Wikipedia: Quasar)_

## Sources

- [Wikipedia: Quasar](https://en.wikipedia.org/wiki/Quasar)

## Cite this case file

Easterling, Marcus. "Quasi-Stellar." The Detail Department (DetailEnjoyer), case file DD-106, last updated Dec 4, 2023. https://detailenjoyer.com/case/quasi-stellar/