EmbeddingGemma 2: an open, lightweight multimodal embedding model
deepmind.google·6d ago
AI Engineering
Hacker News·Aug 21·5 min read
Radiation damage to Hubble has been 4.3 years out of phase with the Solar cycle
TL;DR
Hubble Space Telescope's CCD detectors have experienced radiation damage that is 4.3 years out of sync with the Solar cycle, complicating predictions of damage rates. This finding emphasizes the need for ongoing monitoring of radiation effects on spacecraft.
✦ Why It Matters
Monitor radiation effects on spacecraft to enhance mission planning and longevity.
Key Takeaways
- Monitor radiation damage to improve spacecraft lifespan predictions.
- Utilize CCD detectors for dual purposes: imaging and radiation measurement.
- Explore functional forms for better fitting of radiation damage data.
- Consider the unique radiation environment of Low Earth Orbit in mission planning.
Full Summary
The Hubble Space Telescope, operational for over 24 years, utilizes its CCD (Charge-Coupled Device) detectors not only for capturing stunning images but also as sensitive radiation dosimeters. Researchers found that the radiation damage these detectors experience varies with the Solar cycle, specifically being 4.3 years out of phase with solar phenomena like sunspots and coronal mass ejections.
By fitting functional forms to the time series data of radiation damage, they achieved over 99.5% correction of damage effects on image quality, although the parameters derived were physically unreasonable. In contrast, using physically plausible parameters resulted in poorer performance.
These results underscore the unique radiation environment in Low Earth Orbit and highlight the importance of continuous monitoring of radiation effects on spacecraft to enhance predictions of their operational lifespan.