The Polarimetric and Helioseismic Imager on Solar Orbiter · HackerPapers discussionshttps://hackerpaper.kaipfister.de/p/1903.11061/Collected HN comments and submissions linking this paper.enMon, 02 Nov 2026 11:16:22 GMTThe Polarimetric and Helioseismic Imager on Solar Orbiter — mentioned by mturmonhttps://news.ycombinator.com/item?id=42230546urn:hackerpapers:mention:1903.11061:42230546Sun, 24 Nov 2024 21:02:03 GMT<p>As you mention, the leftmost image (the red &quot;photogram&quot; intending to show intensity) is filtered. I&#x27;m writing mostly to amplify your comment because I spent some years working with these images. People may not be aware how strongly filtered it is. The PHI imager is using 6 very narrow (&lt;&lt;0.1 nm) passbands, all centered about one absorption line (Fe I, 317nm, as you mention). It&#x27;s insanely narrowband. From the abstract of the paper (https://arxiv.org/pdf/1903.11061) describing the instrument: &gt; SO/PHI measures the Zeeman effect and the Doppler shift in the Fe i 617.3 nm spectral line. To this…</p><p><a href="https://hackerpaper.kaipfister.de/p/1903.11061/">Paper and discussion history</a>. A mention is not an endorsement.</p>astro-ph.IM