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XMM-Newton SOC Home Page - XMM-Newton
Welcome to the XMM-Newton Science Operations Centre
The European Space Agency's (ESA) X-ray Multi-Mirror Mission (XMM-Newton) was launched by an Ariane 504 on December 10th 1999. XMM-Newton is ESA's second cornerstone of the Horizon 2000 Science Programme. It carries 3 high throughput X-ray telescopes with an unprecedented effective area, and an optical monitor, the first flown on a X-ray observatory. The large collecting area and ability to make long uninterrupted exposures provide highly sensitive observations.
Since Earth's atmosphere blocks out all X-rays, only a telescope in space can detect and study celestial X-ray sources. The XMM-Newton mission is helping scientists to solve a number of cosmic mysteries, ranging from the enigmatic black holes to the origins of the Universe itself. Observing time on XMM-Newton is being made available to the scientific community, applying for observational periods on a competitive basis.
Read more about the spacecraft, mirrors and instruments and about the XMM-Newton SOC.
News and Highlights
XMM-Newton sees comet 3I/ATLAS in X-ray light
XMM-Newton's EPIC-pn camera observed interstellar comet 3I/ATLAS for ~20 hours, revealing a bright low-energy X-ray glow created as gas from the comet collides with the solar wind—highlighting hard-to-detect gases like H₂ and N₂. The observation offers a rare X-ray look at an interstellar visitor, complementing other telescopes to probe its composition. A video about this discovery, "NEW OBSERVATION! 3I/ATLAS Emits X-Rays as It Passes Through Our Solar System" by NASA Space News, is available on YouTube.
Further details on ESA.int web portal.
XMM-Newton Announcement of Opportunity (AO-25) Closed
The Twenty-fifth Announcement of Opportunity (AO-25) for XMM-Newton closed on 10 October 2025.
A total of 463 valid proposals were received for this cycle, which covers a one-year period with 10 Ms of observing time available. In contrast, 85.6 Ms of science time were requested, resulting in an over-subscription factor of 8.6.
This marks a significant increase in over-subscription compared to recent years. The rise is primarily due to reduced available observing time in AO-25, driven by operational constraints such as increased expected radiation levels and the ongoing evolution of the spacecraft’s orbit.
Proposal breakdown:
- Large Programmes: 45 proposals
- Fulfil Programmes: 13 proposals
- Anticipated Target of Opportunity observations: 81 proposals
Joint Programme submissions totalled 114 proposals:
| XMM–NuSTAR: | 43 |
| XMM–HST: | 15 |
| XMM–SWIFT: | 19 |
| XMM–VLT: | 10 |
| XMM–Chandra: | 10 |
| XMM–JWST: | 19 |
| XMM–NRAO: | 12 |
| XMM–XRISM (new): | 9 |
Proposals were submitted by 375 different Principal Investigators from 42 countries. Including co-investigators, approximately 1,700 individual scientists participated in the response the Twenty-fifth Announcement of Opportunity.
