The European Space Agency’s (ESA) Euclid telescope has identified 31 quasars from the universe’s first 800 million years, including the two oldest and most distant examples ever recorded. According to a study published in Astronomy & Astrophysics and led by Daming Yang of Leiden Observatory, these discoveries more than double the number of previously known quasars from this early cosmic era.
Why are these quasars significant for early universe research?
Quasars serve as critical benchmarks for understanding the “cosmic dawn.” These bright cores of galaxies are powered by supermassive black holes that consume vast amounts of matter. Because they shine with the intensity of a trillion stars, they act as beacons that allow astronomers to peer into the universe when it was only 670 million years old—roughly five percent of its current age of 13.8 billion years.
Before the Euclid mission, only nine quasars with a redshift (z-value) of 7 or higher were known to science. By adding 12 new objects to this specific high-redshift category, Euclid has provided researchers with a larger sample size to analyze how massive black holes and galaxies formed so rapidly after the Big Bang.
The light from these record-breaking quasars took more than 13 billion years to reach Earth. Scientists use this light to study the “reionization era,” a pivotal time when the first stars transformed the universe from a dark, cold void into a transparent, ionized space.
How does Euclid outperform previous telescopes?
Euclid’s success lies in its specialized design, which combines a wide field of view with high sensitivity in the near-infrared spectrum. According to Henk Hoekstra, a professor at Leiden Observatory and co-author of the study, the telescope was designed to be an efficient “search engine” for these distant objects. While ground-based telescopes often struggle with the depth and scale required to spot such faint, distant light, Euclid can detect quasars that are 10 to 100 times dimmer than those identified by previous surveys.
Comparison: Euclid vs. Existing Observations
| Metric | Previous Surveys | Euclid Survey |
|---|---|---|
| Known z > 7 Quasars | 9 | 21 (Cumulative) |
| Survey Area | Limited/Targeted | 1,900 square degrees |
What is the next step for the Euclid mission?
The current findings cover an area of 1,900 square degrees, but this is only the beginning. The mission is scheduled to span six years, eventually mapping a much larger portion of the sky. Huub Röttgering, a professor at Leiden Observatory, notes that current astrophysical models struggle to explain how black holes and galaxies grew so large so quickly. By increasing the number of observed quasars, researchers hope to refine these models and resolve long-standing questions about the speed of early cosmic evolution.
Future data releases may include objects with a redshift greater than 8, which would correspond to a universe younger than 640 million years. These observations will likely continue to push the boundaries of current observational technology.
Pro Tip: Tracking Cosmic History
If you are interested in following the progress of the Euclid mission, you can monitor the official ESA Euclid portal. The team expects to discover hundreds of additional quasars by the time the primary survey concludes in 2030.
Frequently Asked Questions
What are the new record-holding quasars?
The two most distant quasars discovered are EUCL J172902.75+641018.1 and EUCL J125308.55+705432.3, with redshifts of 7.77 and 7.69 respectively.
Why is it difficult to find these objects?
These quasars are extremely distant and faint. Their light has been traveling for over 13 billion years, requiring highly sensitive near-infrared instruments to detect them amidst the vast, dark backdrop of space.
What is the “reionization era”?
It was a period in the early universe when the light from the first stars and quasars ionized the surrounding neutral hydrogen, making the universe transparent to ultraviolet light.
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