{"id":1975,"date":"2026-09-27T17:16:00","date_gmt":"2026-09-27T17:16:00","guid":{"rendered":"https:\/\/stadiaorg.com\/?page_id=1975"},"modified":"2026-09-27T17:16:04","modified_gmt":"2026-09-27T17:16:04","slug":"space-instruments","status":"publish","type":"page","link":"https:\/\/stadiaorg.com\/es\/astronomy-science\/space-instruments\/","title":{"rendered":"Ciencia de la astronom\u00eda Instrumentos espaciales"},"content":{"rendered":"\n\n<article id=\"sv-space-ch2\" lang=\"en\" aria-labelledby=\"svs-title\">\n<style>\n#sv-space-ch2{--svs-ink:#111530;--svs-muted:#52627b;--svs-purple:#6351d5;--svs-blue:#215ea7;--svs-line:#dcdff0;--svs-light:#f6f7fc;--svs-dark:#141634;--svs-green:#146452;--svs-amber:#8b4809;box-sizing:border-box;background:#fff;color:var(--svs-ink);font-family:Arial,Helvetica,sans-serif;font-size:17px;line-height:1.72;overflow-wrap:anywhere;width:100%;margin:0 auto;padding:24px 0 90px;isolation:isolate}\n#sv-space-ch2 *,#sv-space-ch2 *::before,#sv-space-ch2 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Read a landscape. Time a pulse. Sort particles. Follow the instrument from a scientific question to a measurement you can trust.<\/p>\n<div class=\"svs-actions\"><a class=\"svs-button primary\" href=\"#svs-start\">Start the journey \u2193<\/a><a class=\"svs-button ghost\" href=\"#svs-lab-filter\">Try a mini-lab<\/a><\/div>\n<\/div><figure class=\"svs-figure \"><div class=\"svs-image-frame\"><img fetchpriority=\"high\" src=\"https:\/\/www.esa.int\/var\/esa\/storage\/images\/esa_multimedia\/images\/2023\/01\/exploring_jupiter_and_ganymede_artist_s_impression\/24680946-1-eng-GB\/Exploring_Jupiter_and_Ganymede_artist_s_impression_pillars.jpg\" alt=\"Artist\u2019s impression of the Juice spacecraft near Ganymede with Jupiter in the background.\" width=\"1000\" height=\"563\" loading=\"eager\" decoding=\"async\" referrerpolicy=\"no-referrer\"><span class=\"svs-kind\">Artist\u2019s impression<\/span><div class=\"svs-image-unavailable\" hidden>Image not loaded.<br><a href=\"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2023\/01\/Exploring_Jupiter_and_Ganymede_artist_s_impression\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Open the official image and caption<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><\/div><\/div><figcaption>Juice near Ganymede. This is a scene from a cinematic animation, not an image of the spacecraft at Jupiter.<span class=\"svs-credit\">Credit: ESA (acknowledgement: ATG Medialab). <a href=\"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2023\/01\/Exploring_Jupiter_and_Ganymede_artist_s_impression\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Original &amp; full caption<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a> \u00b7 <a href=\"https:\/\/www.esa.int\/ESA_Multimedia\/Terms_and_conditions_of_use_of_images_and_videos_available_on_the_esa_website\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">ESA Standard Licence<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a>.<\/span><\/figcaption><\/figure><\/header>\n<div class=\"svs-quick\"><div><strong>For students &amp; curious readers<\/strong><span>Suggested level: upper secondary and introductory university. No telescope needed.<\/span><\/div><div><strong>Read, calculate, question<\/strong><span>A 25\u201335 minute reading route, with optional mini-labs and deeper sources.<\/span><\/div><div><strong>Evidence, not just pictures<\/strong><span>Real observations are labelled separately from illustrations and classroom models.<\/span><\/div><\/div>\n<nav class=\"svs-toc\" aria-label=\"Chapter contents\"><strong>Choose your route<\/strong><div class=\"svs-toc-links\"><a href=\"#svs-start\">The method<\/a><a href=\"#svs-sun\">1 \u00b7 Hide the Sun<\/a><a href=\"#svs-mars\">2 \u00b7 Read Mars<\/a><a href=\"#svs-mercury\">3 \u00b7 Time a pulse<\/a><a href=\"#svs-particles\">4 \u00b7 Sort particles<\/a><a href=\"#svs-gamma\">5 \u00b7 Catch a flash<\/a><a href=\"#svs-surfaces\">6 \u00b7 Trust a surface<\/a><a href=\"#svs-earth\">Back on Earth<\/a><a href=\"#svs-videos\">Watch &amp; discuss<\/a><a href=\"#svs-frontiers\">Research continues<\/a><a href=\"#svs-quiz\">Test your understanding<\/a><a href=\"#svs-teachers\">For educators<\/a><a href=\"#svs-sources\">Sources &amp; credits<\/a><\/div><\/nav>\n\n<section class=\"svs-section\" id=\"svs-start\"><div class=\"svs-intro\"><span class=\"svs-kicker\">Before the first observation<\/span><h2>A beautiful image is a beginning.<br>What does it actually tell us?<\/h2>\n<p>A useful starting habit is to ask four questions of every scientific image: <strong>What was measured? By which instrument? How was it processed? Which conclusion does it support?<\/strong> In this chapter, keep an observation separate from an interpretation, and both separate from an artist\u2019s impression.<\/p>\n<p>Light can be reflected, transmitted or absorbed; its interaction with matter depends on wavelength. Instruments exploit those differences to select information rather than simply to make a scene brighter. <span class=\"svs-cites\"><a href=\"#svs-source-1\" aria-label=\"Source 1\">[1]<\/a><\/span><\/p><\/div>\n<ol class=\"svs-chain\"><li><strong>Question<\/strong>Choose something that could be answered by a measurement.<\/li><li><strong>Instrument<\/strong>Decide which signal can carry the information.<\/li><li><strong>Measurement<\/strong>Calibrate, record conditions and estimate uncertainty.<\/li><li><strong>Interpretation<\/strong>Compare explanations and state what remains unresolved.<\/li><\/ol>\n<div class=\"svs-note green\"><strong>Your notebook:<\/strong> for each stop, write one observation, one interpretation and one limitation. You will use them in the final challenge.<\/div>\n<\/section>\n<section class=\"svs-section\" id=\"svs-sun\"><div class=\"svs-split\"><div class=\"svs-copy\"><span class=\"svs-kicker\">01 \u00b7 Solar Orbiter \/ Metis<\/span><h2>To see more,<br>start by hiding the brightest light.<\/h2>\n<p class=\"svs-question\">Can receiving less light give us more useful information?<\/p>\n<p>Metis is a coronagraph on Solar Orbiter. By blocking the bright solar disc, it allows the much fainter corona \u2014 the Sun\u2019s outer atmosphere \u2014 to be recorded. It observes visible and ultraviolet emission. The published first-light images use assigned colours to distinguish the bands; the colours are not a naked-eye view. <span class=\"svs-cites\"><a href=\"#svs-source-2\" aria-label=\"Source 2\">[2]<\/a><\/span><\/p>\n<p>This is a lesson in <strong>contrast<\/strong>. Collecting more unwanted light may bury a weak signal. An optical design must control stray light and choose which wavelengths reach the detector. <span class=\"svs-cites\"><a href=\"#svs-source-1\" aria-label=\"Source 1\">[1]<\/a><a href=\"#svs-source-2\" aria-label=\"Source 2\">[2]<\/a><\/span><\/p>\n<details class=\"svs-detail \"><summary>Think first: does the black centre mean the Sun is missing?<\/summary><div class=\"svs-answer\"><p>No. In these coronagraph images the central region is deliberately blocked. A missing signal can be a consequence of the instrument rather than the absence of the object.<\/p><\/div><\/details>\n<div class=\"svs-note warning\"><strong>Safety:<\/strong> use only the images and calculations on this page. Do not copy a coronagraph by pointing an unfiltered camera, binoculars or telescope at the Sun. Eclipse glasses do not make unfiltered optical instruments safe. <span class=\"svs-cites\"><a href=\"#svs-source-20\" aria-label=\"Source 20\">[20]<\/a><\/span><\/div>\n<\/div><figure class=\"svs-figure \"><div class=\"svs-image-frame\"><img loading=\"lazy\" src=\"https:\/\/www.esa.int\/var\/esa\/storage\/images\/esa_multimedia\/images\/2020\/07\/solar_orbiter_s_first_view_of_the_sun_s_corona\/22133738-1-eng-GB\/Solar_Orbiter_s_first_view_of_the_Sun_s_corona_pillars.jpg\" alt=\"Four Metis coronagraph observations with the central solar disc masked; green and red display colours distinguish bands.\" width=\"1000\" height=\"1000\" loading=\"lazy\" decoding=\"async\" referrerpolicy=\"no-referrer\"><span class=\"svs-kind\">Observation \u00b7 assigned colours<\/span><div class=\"svs-image-unavailable\" hidden>Image not loaded.<br><a href=\"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2020\/07\/Solar_Orbiter_s_first_view_of_the_Sun_s_corona\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Open the official image and caption<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><\/div><\/div><figcaption>Metis observations from May and June 2020. Green represents a visible-light band; red represents ultraviolet. The dark centre is an instrumental occultation, not a hole in the Sun.<span class=\"svs-credit\">Credit: ESA &#038; NASA\/Solar Orbiter\/Metis Team. <a href=\"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2020\/07\/Solar_Orbiter_s_first_view_of_the_Sun_s_corona\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Original &amp; full caption<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a> \u00b7 <a href=\"https:\/\/www.esa.int\/ESA_Multimedia\/Terms_and_conditions_of_use_of_images_and_videos_available_on_the_esa_website\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">ESA Standard Licence<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a>.<\/span><\/figcaption><\/figure><\/div>\n<div class=\"svs-lab\" id=\"svs-lab-filter\"><span class=\"svs-kicker\">Mini-lab A \u00b7 Synthetic data \u00b7 5 minutes<\/span><h3>Can a filter improve the measurement?<\/h3>\n<p>Imagine one exposure containing <strong>100 signal counts<\/strong> and <strong>900 background counts<\/strong>. A hypothetical filter transmits 80% of the signal and 10% of the background. These numbers are invented for learning; they are not a Metis or coating specification.<\/p>\n<div class=\"svs-control-grid svs-js-only\" hidden><div><label for=\"svs-signal\">Signal transmitted: <output id=\"svs-signal-label\" for=\"svs-signal\">80%<\/output><\/label><input id=\"svs-signal\" type=\"range\" min=\"0\" max=\"100\" step=\"1\" value=\"80\"><\/div><div><label for=\"svs-background\">Background transmitted: <output id=\"svs-background-label\" for=\"svs-background\">10%<\/output><\/label><input id=\"svs-background\" type=\"range\" min=\"0\" max=\"100\" step=\"1\" value=\"10\"><\/div><\/div>\n<div class=\"svs-metrics\" aria-live=\"polite\" aria-atomic=\"true\"><div><small>Signal counts after the filter<\/small><strong id=\"svs-out-signal\">80<\/strong><\/div><div><small>Background counts after the filter<\/small><strong id=\"svs-out-background\">90<\/strong><\/div><div><small>Useful fraction of detected counts<\/small><strong id=\"svs-out-fraction\">47.1%<\/strong><\/div><\/div>\n<div class=\"svs-track\" aria-hidden=\"true\"><span id=\"svs-signal-bar\" class=\"signal\" style=\"width:47.06%\"><\/span><span id=\"svs-background-bar\" class=\"background\" style=\"width:52.94%\"><\/span><\/div><p class=\"svs-mini\">Purple: useful signal. Grey: background. Before filtering the useful fraction was 10%.<\/p>\n<details class=\"svs-detail \"><summary>Worked solution \u00b7 signal fraction is not the whole answer<\/summary><div class=\"svs-answer\"><p>Signal: 100 \u00d7 0.80 = <strong>80<\/strong>. Background: 900 \u00d7 0.10 = <strong>90<\/strong>. The useful fraction is 80 \/ (80 + 90) = <strong>47.1%<\/strong>.<\/p><p>Under an ideal, photon-counting model with independent Poisson counts, a known mean background and no read-noise or dark-current contribution, a simple signal-to-noise estimate is <strong>S \/ \u221a(S + B)<\/strong>. It rises from 3.16 to 6.14 for these default values. A real background estimate adds its own uncertainty. Losing too much signal can make the measurement worse even while the useful fraction rises.<\/p><p><strong>Challenge:<\/strong> keep 10% of the signal and 0% of the background. The useful fraction becomes 100%, but only ten signal counts remain. Explain why \u201call useful\u201d does not mean \u201cprecise\u201d.<\/p><\/div><\/details>\n<p class=\"svs-mini\">No software? The default numbers and worked solution remain readable without JavaScript.<\/p><\/div><\/section>\n\n<section class=\"svs-section\" id=\"svs-mars\"><div class=\"svs-split reverse\"><figure class=\"svs-figure \"><div class=\"svs-image-frame\"><img loading=\"lazy\" src=\"https:\/\/www.esa.int\/var\/esa\/storage\/images\/esa_multimedia\/images\/2019\/09\/oyama_crater_mars\/19702893-1-eng-GB\/Oyama_Crater_Mars_pillars.png\" alt=\"CaSSIS processed-colour view of layered terrain inside Oyama Crater on Mars.\" width=\"1000\" height=\"1000\" loading=\"lazy\" decoding=\"async\" referrerpolicy=\"no-referrer\"><span class=\"svs-kind\">Observation \u00b7 processed colour<\/span><div class=\"svs-image-unavailable\" hidden>Image not loaded.<br><a href=\"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2019\/09\/Oyama_Crater_Mars\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Open the official image and caption<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><\/div><\/div><figcaption>Oyama Crater, 13 June 2019. Colour differences help compare terrain. The source discusses mineral evidence from OMEGA and CRISM alongside the CaSSIS image: colour alone is not a chemical identification.<span class=\"svs-credit\">Credit: ESA\/Roscosmos\/CaSSIS. <a href=\"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2019\/09\/Oyama_Crater_Mars\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Original &amp; full caption<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a> \u00b7 <a href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/3.0\/igo\/\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">CC BY-SA 3.0 IGO<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a>.<\/span><\/figcaption><\/figure><div class=\"svs-copy\"><span class=\"svs-kicker\">02 \u00b7 Mars \/ CaSSIS<\/span><h2>A landscape is also a dataset.<\/h2><p class=\"svs-question\">Can an image tell us what a rock is made of?<\/p>\n<p>CaSSIS \u2014 the Colour and Stereo Surface Imaging System \u2014 is a camera on the ExoMars Trace Gas Orbiter, developed under the leadership of the University of Bern. It images the surface; it is <strong>not the instrument that directly analyses atmospheric gases<\/strong>. <span class=\"svs-cites\"><a href=\"#svs-source-3\" aria-label=\"Source 3\">[3]<\/a><\/span><\/p>\n<p>Its coloured views combine measurements through filters. Stereo observations view terrain from different geometries, allowing relief to be reconstructed. The instrument team also calibrates and assembles small image framelets into the final view: a scientific image is a processed measurement, not an unexamined camera output. <span class=\"svs-cites\"><a href=\"#svs-source-5\" aria-label=\"Source 5\">[5]<\/a><\/span><\/p>\n<p>For Oyama Crater, the source compares CaSSIS terrain patterns with mineral information from spectrometers on other spacecraft. This is a useful example of <strong>combining evidence<\/strong>, rather than declaring a mineral from one displayed colour. <span class=\"svs-cites\"><a href=\"#svs-source-4\" aria-label=\"Source 4\">[4]<\/a><\/span><\/p>\n<details class=\"svs-detail \"><summary>A safe desk activity: your two viewpoints<\/summary><div class=\"svs-answer\"><p>Hold a thumb at arm\u2019s length in front of a distant indoor object. Look with one eye, then the other, keeping your head still. The apparent displacement illustrates parallax. Repeat with the thumb closer. This is an analogy for the geometry of stereo imaging, not a method for calculating a Mars height from these pictures.<\/p><\/div><\/details>\n<div class=\"svs-actions\"><a href=\"https:\/\/observations.cassis.unibe.ch\/\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"svs-button\">Explore the CaSSIS observation browser \u2197<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a> <a href=\"https:\/\/www.cassis.unibe.ch\/\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"svs-button\">CaSSIS images &amp; background \u2197<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><\/div><p class=\"svs-mini\">The observation browser is external and requires JavaScript. The university site is a text-based alternative.<\/p>\n<\/div><\/div><\/section>\n<section class=\"svs-section\" id=\"svs-mercury\"><div class=\"svs-split\"><div class=\"svs-copy\"><span class=\"svs-kicker\">03 \u00b7 Mercury \/ BepiColombo \/ BELA<\/span><h2>Turn a clock<br>into a ruler.<\/h2><p class=\"svs-question\">How can a light pulse measure a planet?<\/p>\n<p>BELA, the BepiColombo Laser Altimeter, measures the time between an emitted laser pulse and its detected return from the surface. A receiving telescope, narrow-band filter and detector help distinguish the return from unwanted light. <span class=\"svs-cites\"><a href=\"#svs-source-6\" aria-label=\"Source 6\">[6]<\/a><\/span><\/p>\n<p>The elapsed time describes a <strong>round trip<\/strong>. In a simple model, distance is the speed of light multiplied by time, divided by two. A range is not yet a terrain map: spacecraft position and pointing, calibration and a reference shape are also needed. <span class=\"svs-cites\"><a href=\"#svs-source-6\" aria-label=\"Source 6\">[6]<\/a><\/span><\/p>\n<p class=\"svs-caption-note\">The photograph beside this text was taken by a BepiColombo monitoring camera, not by BELA. Different instruments on one mission answer different questions. <span class=\"svs-cites\"><a href=\"#svs-source-7\" aria-label=\"Source 7\">[7]<\/a><\/span><\/p>\n<details class=\"svs-detail \"><summary>Why does a filter help an altimeter?<\/summary><div class=\"svs-answer\"><p>The useful return is in the laser\u2019s wavelength band. A filter can reduce other incoming wavelengths. That does not remove all background, and the design must allow for the instrument\u2019s operating conditions.<\/p><\/div><\/details>\n<\/div><figure class=\"svs-figure \"><div class=\"svs-image-frame\"><img loading=\"lazy\" src=\"https:\/\/www.esa.int\/var\/esa\/storage\/images\/esa_multimedia\/images\/2021\/10\/hello_mercury\/23492679-1-eng-GB\/Hello_Mercury_pillars.png\" alt=\"Black-and-white Mercury flyby photograph with spacecraft structures in the foreground.\" width=\"1000\" height=\"1000\" loading=\"lazy\" decoding=\"async\" referrerpolicy=\"no-referrer\"><span class=\"svs-kind\">Observation \u00b7 monitoring camera<\/span><div class=\"svs-image-unavailable\" hidden>Image not loaded.<br><a href=\"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2021\/10\/Hello_Mercury\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Open the official image and caption<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><\/div><\/div><figcaption>Mercury seen by BepiColombo\u2019s Monitoring Camera 2 on 1 October 2021. This photograph provides context: it is not a BELA altitude map.<span class=\"svs-credit\">Credit: ESA\/BepiColombo\/MTM. <a href=\"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2021\/10\/Hello_Mercury\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Original &amp; full caption<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a> \u00b7 <a href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/3.0\/igo\/\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">CC BY-SA 3.0 IGO<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a>.<\/span><\/figcaption><\/figure><\/div>\n<div class=\"svs-lab\" id=\"svs-lab-range\"><span class=\"svs-kicker\">Mini-lab B \u00b7 Synthetic model \u00b7 5 minutes<\/span><h3>Measure a distance with milliseconds<\/h3><p>Use the rounded classroom value <strong>c \u2248 300,000 km\/s<\/strong>. Assume a stationary instrument, a straight path and no instrumental delay. This calculator is not a BELA flight-data tool.<\/p>\n<div class=\"svs-formula\">distance = speed of light \u00d7 round-trip time \/ 2<\/div>\n<div class=\"svs-control-grid svs-js-only\" hidden><div><label for=\"svs-time\">Round-trip delay (milliseconds)<\/label><input id=\"svs-time\" type=\"number\" min=\"0\" max=\"1000\" step=\"0.1\" value=\"4\"><\/div><div><label for=\"svs-time-error\">Timing uncertainty (nanoseconds)<\/label><input id=\"svs-time-error\" type=\"number\" min=\"0\" max=\"1000\" step=\"1\" value=\"2\"><\/div><\/div>\n<div class=\"svs-metrics\" aria-live=\"polite\" aria-atomic=\"true\"><div><small>One-way range<\/small><strong id=\"svs-distance\">600.0 <span class=\"svs-unit\">km<\/span><\/strong><\/div><div><small>Range uncertainty from timing alone<\/small><strong id=\"svs-range-error\">0.30 <span class=\"svs-unit\">m<\/span><\/strong><\/div><div><small>Travel counted<\/small><strong>2 <span class=\"svs-unit\">legs<\/span><\/strong><\/div><\/div>\n<p id=\"svs-range-status\" class=\"svs-mini\" aria-live=\"polite\">Other uncertainty sources are intentionally omitted.<\/p>\n<details class=\"svs-detail \"><summary>Worked solution and the missing information<\/summary><div class=\"svs-answer\"><p>4 ms = 0.004 s. Therefore 300,000 \u00d7 0.004 \/ 2 = <strong>600 km<\/strong>. For 2 ns, the timing contribution is 300,000,000 \u00d7 2 \u00d7 10<sup>\u22129<\/sup> \/ 2 = <strong>0.30 m<\/strong>.<\/p><p>That 0.30 m is not total map accuracy. Ask about orbit knowledge, pointing, surface slope, return-pulse shape, calibration and the chosen reference surface.<\/p><\/div><\/details>\n<\/div><\/section>\n\n<section class=\"svs-section\" id=\"svs-particles\"><span class=\"svs-kicker\">04 \u00b7 Jupiter\u2019s icy moons \/ Juice \/ NIM<\/span><div class=\"svs-intro\"><h2>Not every spectrum is made of light.<\/h2><p class=\"svs-question\">How do you sample the very thin gas around a moon?<\/p>\n<p>Juice is designed to study Jupiter and the icy moons Ganymede, Callisto and Europa. Its instruments do not all take photographs. The Bern-led <strong>Neutral and Ion Mass Spectrometer, NIM<\/strong>, is part of the Particle Environment Package and is designed to analyse tenuous neutral gas and ions. <span class=\"svs-cites\"><a href=\"#svs-source-8\" aria-label=\"Source 8\">[8]<\/a><a href=\"#svs-source-9\" aria-label=\"Source 9\">[9]<\/a><\/span><\/p>\n<p>For neutral samples, an ion source creates charged particles. An analyser separates them by <strong>mass-to-charge ratio<\/strong>, and a detector records arrival times. The ion mirror in this instrument uses electric fields: it is not a reflective optical coating. <span class=\"svs-cites\"><a href=\"#svs-source-8\" aria-label=\"Source 8\">[8]<\/a><\/span><\/p><\/div>\n<ol class=\"svs-chain\"><li><strong>Sample<\/strong>Let atoms and molecules enter the instrument.<\/li><li><strong>Ionise &amp; guide<\/strong>Create or collect ions and guide their motion.<\/li><li><strong>Separate<\/strong>Use time of flight to distinguish mass-to-charge ratios.<\/li><li><strong>Record<\/strong>Convert arrival-time signals into a calibrated mass spectrum.<\/li><\/ol>\n<p class=\"svs-caption-note\">A mass peak must be interpreted with calibration, possible overlapping species and the instrument response in mind. An instrument concept is not, by itself, evidence of an ocean\u2019s composition or of life.<\/p>\n<div class=\"svs-lab\" id=\"svs-lab-tof\"><span class=\"svs-kicker\">Mini-lab C \u00b7 Simplified time of flight \u00b7 5 minutes<\/span><h3>Which ion arrives first?<\/h3><p>Give two ions the same charge, accelerate them through the same voltage, and compare equal flight paths. In this simplified non-relativistic model, flight time is proportional to the square root of mass-to-charge ratio. Ignore starting velocity and energy spread.<\/p>\n<div class=\"svs-formula\">t<sub>2<\/sub> \/ t<sub>1<\/sub> = \u221a[(m<sub>2<\/sub>\/q<sub>2<\/sub>) \/ (m<sub>1<\/sub>\/q<sub>1<\/sub>)]<\/div>\n<div class=\"svs-js-only\" hidden><label for=\"svs-mass-ratio\">Mass-to-charge ratio relative to ion 1: <output for=\"svs-mass-ratio\" id=\"svs-mass-label\">4<\/output><\/label><input id=\"svs-mass-ratio\" type=\"range\" min=\"1\" max=\"16\" step=\"1\" value=\"4\"><\/div>\n<div class=\"svs-metrics\" aria-live=\"polite\"><div><small>Ion 1: reference flight time<\/small><strong>1.00 <span class=\"svs-unit\">unit<\/span><\/strong><\/div><div><small>Ion 2: relative flight time<\/small><strong id=\"svs-tof-time\">2.00 <span class=\"svs-unit\">units<\/span><\/strong><\/div><div><small>Assumptions<\/small><strong>Equal <span class=\"svs-unit\">voltage &amp; path<\/span><\/strong><\/div><\/div>\n<details class=\"svs-detail \"><summary>Why twice the time, not four times?<\/summary><div class=\"svs-answer\"><p>The acceleration supplies kinetic energy qV = \u00bdmv\u00b2. Solving gives v = \u221a(2qV\/m). Since t = L\/v, time scales as \u221a(m\/q). A fourfold mass-to-charge ratio gives a <strong>twofold<\/strong> time, not fourfold.<\/p><p>NIM has a more sophisticated ion-optical design. This model illustrates a principle and should not be used to simulate its calibration or resolution.<\/p><\/div><\/details>\n<\/div><\/section>\n<section class=\"svs-section\" id=\"svs-gamma\"><div class=\"svs-split\"><div class=\"svs-copy\"><span class=\"svs-kicker\">05 \u00b7 Ground-based astronomy \/ CTAO<\/span><h2>Use the atmosphere<br>as part of the detector.<\/h2><p class=\"svs-question\">What reaches the mirror when the original gamma ray does not?<\/p>\n<p>A high-energy gamma ray interacting in the atmosphere can produce an air shower. Charged secondary particles moving faster than light travels <em>in that medium<\/em> produce a brief Cherenkov flash. They do not outrun light in a vacuum. <span class=\"svs-cites\"><a href=\"#svs-source-10\" aria-label=\"Source 10\">[10]<\/a><\/span><\/p>\n<p>Cherenkov telescopes collect the resulting light, not the original gamma ray. Fast cameras record the flash; multiple views and analysis help reconstruct the shower and distinguish candidate gamma-ray events from backgrounds. <span class=\"svs-cites\"><a href=\"#svs-source-10\" aria-label=\"Source 10\">[10]<\/a><\/span><\/p>\n<details class=\"svs-detail \"><summary>The same phenomenon at CERN<\/summary><div class=\"svs-answer\"><p>LHCb uses ring-imaging Cherenkov detectors, or RICH detectors, for particle identification. Here the medium and detector geometry are engineered in a particle experiment rather than provided by the atmosphere. A shared physical effect does not make these the same instrument.<\/p><span class=\"svs-cites\"><a href=\"#svs-source-11\" aria-label=\"Source 11\">[11]<\/a><\/span><\/div><\/details>\n<div class=\"svs-actions\"><a href=\"https:\/\/www.eso.org\/public\/videos\/eso2521a\/\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"svs-button primary\">Watch the 7-minute ESO explainer \u2197<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><\/div>\n<\/div><figure class=\"svs-figure \"><div class=\"svs-image-frame\"><img loading=\"lazy\" src=\"https:\/\/cdn.eso.org\/images\/screen\/eso1841h.jpg\" alt=\"Artist\u2019s rendering of an array of medium-sized Cherenkov telescopes beneath a night sky.\" width=\"1000\" height=\"563\" loading=\"lazy\" decoding=\"async\" referrerpolicy=\"no-referrer\"><span class=\"svs-kind\">Artist\u2019s impression \u00b7 2018<\/span><div class=\"svs-image-unavailable\" hidden>Image not loaded.<br><a href=\"https:\/\/www.eso.org\/public\/images\/eso1841h\/\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Open the official image and caption<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><\/div><\/div><figcaption>A 2018 concept illustration of Cherenkov telescopes, distributed by ESO. It is not a photograph of the completed observatory and is not used here to specify its final layout.<span class=\"svs-credit\">Credit: CTAO. <a href=\"https:\/\/www.eso.org\/public\/images\/eso1841h\/\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Original &amp; full caption<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a> \u00b7 <a href=\"https:\/\/www.eso.org\/public\/outreach\/copyright\/\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">CC BY 4.0 via ESO<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a>.<\/span><\/figcaption><\/figure><\/div>\n<div class=\"svs-note\"><strong>Do not confuse the steps:<\/strong> gamma-ray interaction \u2192 particle shower \u2192 Cherenkov light \u2192 mirror and camera \u2192 reconstructed event. A bright pixel is not yet a confirmed cosmic source.<\/div>\n<\/section>\n\n<section class=\"svs-section\" id=\"svs-surfaces\"><span class=\"svs-kicker\">06 \u00b7 Functional surfaces &amp; experimental validation<\/span><div class=\"svs-intro\"><h2>A layer is not a label.<br>It is a set of measured properties.<\/h2>\n<p>Reflection, transmission and electrical behaviour are different requirements. NASA has investigated transparent conductive coatings that dissipate electrical charge while preserving useful optical transmission. That is a public example of a design trade-off, not a claim about a particular supplier or mission component. <span class=\"svs-cites\"><a href=\"#svs-source-12\" aria-label=\"Source 12\">[12]<\/a><\/span><\/p>\n<p>A useful classroom question is not \u201cDoes the surface look clear?\u201d but <strong>\u201cWhich properties have actually been measured, under what conditions?\u201d<\/strong> Passing an optical check does not by itself establish an electrical or environmental requirement.<\/p>\n<p>Even a single functional layer may require substantial development. Its qualification must be tied to a defined use, with acceptance criteria specified before testing.<\/p><\/div>\n<div class=\"svs-lab\"><span class=\"svs-kicker\">Evidence challenge \u00b7 Invented classroom data<\/span><h3>Same transparency. Same component?<\/h3><p>For this exercise only, require visible transmission of at least <strong>85%<\/strong> and sheet resistance no greater than <strong>50 \u03a9\/\u25a1<\/strong>, both before and after a specified laboratory test. All values below are synthetic; they describe no TFP product and no mission requirement. Measurement uncertainties are omitted from this introductory decision.<\/p>\n<div class=\"svs-table-wrap\"><table><caption class=\"svs-sr\">Invented transparent-conductor measurements before and after a test<\/caption><thead><tr><th scope=\"col\">Sample<\/th><th scope=\"col\">Transmission<br>before \u2192 after<\/th><th scope=\"col\">Sheet resistance<br>before \u2192 after<\/th><\/tr><\/thead><tbody><tr><th scope=\"row\">A<\/th><td>90% \u2192 90%<\/td><td>40 \u2192 70 \u03a9\/\u25a1<\/td><\/tr><tr><th scope=\"row\">B<\/th><td>88% \u2192 87%<\/td><td>35 \u2192 38 \u03a9\/\u25a1<\/td><\/tr><tr><th scope=\"row\">C<\/th><td>91% \u2192 83%<\/td><td>30 \u2192 31 \u03a9\/\u25a1<\/td><\/tr><\/tbody><\/table><\/div>\n<details class=\"svs-detail \"><summary>Which sample passes this limited check?<\/summary><div class=\"svs-answer\"><p><strong>B<\/strong> passes both stated thresholds before and after the test. A retains its optical transmission but fails the electrical threshold. C remains electrically acceptable but fails the optical threshold.<\/p><p>This does <strong>not<\/strong> make B space-qualified. We would still need uncertainty estimates, repeatability, a defined test procedure and all the other requirements. Near a threshold, measurement uncertainty affects whether conformity can be claimed.<\/p><\/div><\/details>\n<\/div>\n<\/section>\n<section class=\"svs-section\" id=\"svs-earth\"><div class=\"svs-split reverse\"><figure class=\"svs-figure \"><div class=\"svs-image-frame\"><img loading=\"lazy\" src=\"https:\/\/www.esa.int\/var\/esa\/storage\/images\/esa_multimedia\/images\/2024\/08\/juice_janus_view_of_earth\/26285705-1-eng-GB\/Juice_JANUS_view_of_Earth_pillars.jpg\" alt=\"Grayscale JANUS image of Luzon and clouds acquired during Juice\u2019s Earth flyby.\" width=\"752\" height=\"1000\" loading=\"lazy\" decoding=\"async\" referrerpolicy=\"no-referrer\"><span class=\"svs-kind\">Observation \u00b7 performance check<\/span><div class=\"svs-image-unavailable\" hidden>Image not loaded.<br><a href=\"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2024\/08\/Juice_JANUS_view_of_Earth\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Open the official image and caption<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><\/div><\/div><figcaption>Luzon, Earth, observed by JANUS on 20 August 2024. ESA identifies performance evaluation as the main purpose of these flyby observations. An impressive picture can also be an engineering test.<span class=\"svs-credit\">Credit: ESA\/Juice\/JANUS. <a href=\"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2024\/08\/Juice_JANUS_view_of_Earth\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Original &amp; full caption<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a> \u00b7 <a href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/3.0\/igo\/\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">CC BY-SA 3.0 IGO<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a>.<\/span><\/figcaption><\/figure><div class=\"svs-copy\"><span class=\"svs-kicker\">07 \u00b7 Back on Earth<\/span><h2>Test what you built.<br>Then ask what can be transferred.<\/h2>\n<p>The JANUS camera on Juice took images of Earth during the 2024 flyby primarily to evaluate instrument performance. The scene was familiar; the measurement was still valuable. A real target can help test a system before it reaches its main destination. <span class=\"svs-cites\"><a href=\"#svs-source-14\" aria-label=\"Source 14\">[14]<\/a><\/span><\/p>\n<p>Visible and infrared channels can reveal different aspects of the same scene. Thermal-infrared imaging is sensitive to emitted radiation; other infrared observations also involve reflected light. Interpreting a picture requires knowing the band, the detector and the conditions. <span class=\"svs-cites\"><a href=\"#svs-source-13\" aria-label=\"Source 13\">[13]<\/a><\/span><\/p>\n<div class=\"svs-note\"><strong>An engineering archive example.<\/strong> A brochure supplied for this chapter describes TFP VISION as a terrestrial platform combining visible and infrared imaging. It lists wildlife observation and fire detection among possible uses. This is evidence of the described design and intended applications, not an independent validation of its range or performance.<span class=\"svs-cites\"><a href=\"#svs-archive\">[A]<\/a><\/span><\/div>\n<p>According to the engineer\u2019s account, some expertise from astronomical work was later applied to a terrestrial prototype. The learning question is <strong>what must be re-tested when the use changes<\/strong> \u2014 not whether a space-related origin guarantees performance on Earth.<\/p>\n<details class=\"svs-detail \"><summary>Discuss the responsibility as well as the technology<\/summary><div class=\"svs-answer\"><p>A remote observation system can support environmental monitoring, but observing people also raises privacy questions. In a classroom, use landscapes, published data or non-personal targets. Do not collect or publish identifiable images of people without an appropriate basis and permission.<\/p><\/div><\/details>\n<\/div><\/div><\/section>\n\n<section class=\"svs-section\" id=\"svs-videos\"><span class=\"svs-kicker\">Watch with a question in mind<\/span><h2>A film library, not a scrolling distraction.<\/h2><p>Choose one short film before opening the longer documentary. Each link goes to the institution\u2019s own page. The written question lets you take part even when audio or captions are unavailable.<\/p><p class=\"svs-mini\">No player starts automatically. Language, subtitles and accessibility options depend on the external host. Historical films may mention plans that have since changed; use the current mission pages for schedules.<\/p><div class=\"svs-cards\"><div class=\"svs-card\"><span class=\"svs-video-tag\">ESA \u00b7 00:40 \u00b7 animation + observation<\/span><h3>A solar observation needs geometry<\/h3><p>Watch how a spacecraft trajectory is placed within the Metis field of view.<\/p><a href=\"https:\/\/www.esa.int\/ESA_Multimedia\/Videos\/2023\/09\/How_spacecraft_gymnastics_enabled_joint_Sun_observations\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"svs-button\">Open official film page \u2197<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><div class=\"svs-prompts\"><strong>After watching:<\/strong> Which elements are measured images, and which have been added to explain the geometry?<\/div><\/div><div class=\"svs-card\"><span class=\"svs-video-tag\">ESA \/ University of Bern \u00b7 10:00 \u00b7 image film<\/span><h3>Exploring Mars from orbit<\/h3><p>A guided collection of CaSSIS surface images, published in 2020.<\/p><a href=\"https:\/\/www.esa.int\/esatv\/Videos\/2020\/09\/Exploring_Mars_from_orbit\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"svs-button\">Open official film page \u2197<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><div class=\"svs-prompts\"><strong>After watching:<\/strong> Choose one image: record the scale, the feature you see and an interpretation you would need to test.<\/div><\/div><div class=\"svs-card\"><span class=\"svs-video-tag\">ESO \u00b7 07:02 \u00b7 explainer<\/span><h3>How CTAO will see the high-energy Universe<\/h3><p>An introduction to atmospheric showers and Cherenkov-light telescopes, published December 2025.<\/p><a href=\"https:\/\/www.eso.org\/public\/videos\/eso2521a\/\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"svs-button\">Open official film page \u2197<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><div class=\"svs-prompts\"><strong>After watching:<\/strong> What actually reaches the telescope mirror: the original gamma ray or visible\/near-UV light from an air shower?<\/div><\/div><div class=\"svs-card\"><span class=\"svs-video-tag\">ESA \/ Lightcurve Films \u00b7 2:02:28 \u00b7 documentary<\/span><h3>The making of Juice<\/h3><p>Optional long-form viewing: follow development, testing and launch.<\/p><a href=\"https:\/\/www.esa.int\/ESA_Multimedia\/Videos\/2023\/09\/The_making_of_Juice_the_film\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"svs-button\">Open official film page \u2197<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><div class=\"svs-prompts\"><strong>After watching:<\/strong> Name one test that can fail even when an instrument looks undamaged.<\/div><\/div><div class=\"svs-card\"><span class=\"svs-video-tag\">ESA \/ ATG medialab \u00b7 00:17 \u00b7 animation<\/span><h3>Juice and Ganymede in 17 seconds<\/h3><p>A cinematic animation of the intended encounter, not flight footage at Ganymede.<\/p><a href=\"https:\/\/www.esa.int\/ESA_Multimedia\/Videos\/2023\/01\/Exploring_Jupiter_and_Ganymede_artist_s_impression\/(lang)\/en\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"svs-button\">Open official film page \u2197<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><div class=\"svs-prompts\"><strong>After watching:<\/strong> What can an animation explain, and what cannot it establish as an observation?<\/div><\/div><div class=\"svs-card\"><span class=\"svs-video-tag\">NASA \u00b7 explainer on the mission page<\/span><h3>Roman\u2019s starlight-suppression technology<\/h3><p>The page contains an official video and background on masks and deformable mirrors.<\/p><a href=\"https:\/\/science.nasa.gov\/mission\/roman-space-telescope\/coronagraph\/\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"svs-button\">Open official film page \u2197<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><div class=\"svs-prompts\"><strong>After watching:<\/strong> Why is simply putting a dark disc in front of a star not the end of the optical problem?<\/div><\/div><div class=\"svs-card\"><span class=\"svs-video-tag\">CERN \/ IPPOG \u00b7 about 14 min \u00b7 historical introduction<\/span><h3>LHCb: the Beauty Experiment<\/h3><p>A 2011 introduction for general audiences; detector hardware has since evolved.<\/p><a href=\"https:\/\/ippog.web.cern.ch\/ippog_resource_database\/lhcb-film-lhcb-beauty-experiment-lhcb-lexperience-de-beaute\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"svs-button\">Open official film page \u2197<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><div class=\"svs-prompts\"><strong>After watching:<\/strong> Which observations are turned into evidence about particles that cannot be seen directly?<\/div><\/div><\/div><\/section><section class=\"svs-section\" id=\"svs-frontiers\"><span class=\"svs-kicker\">Research continues \u00b7 reviewed 27 September 2026<\/span><h2>Follow a question into the next project.<\/h2><p>These are starting points for further reading, not claims of institutional partnership with Stadia. An observation, a result and a mission under development are deliberately labelled differently.<\/p><div class=\"svs-cards\"><div class=\"svs-card\"><span class=\"svs-video-tag\">Scuola Normale Superiore \u00b7 Pisa<br>Reported research result<\/span><h3>Why does a galaxy stop forming stars?<\/h3><p>Researchers from the Normale contributed to a Cambridge-led study of GS-10578, reported in January 2026, using Webb and ALMA. Compare what each instrument contributes before accepting a proposed explanation.<span class=\"svs-cites\"><a href=\"#svs-source-15\" aria-label=\"Source 15\">[15]<\/a><\/span><\/p><a href=\"https:\/\/normalenews.sns.it\/individuata-una-delle-piu-antiche-galassie-morte-soffocata-dal-buco-nero-al-suo-interno\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"svs-button\">Follow the research \u2197<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><\/div><div class=\"svs-card\"><span class=\"svs-video-tag\">NASA \u00b7 Roman<br>Instrument \/ technology demonstration<\/span><h3>What else is needed after blocking starlight?<\/h3><p>Roman\u2019s coronagraph combines masks and deformable mirrors to suppress stellar light. Explore the difference between a technology demonstration and a confirmed planetary discovery.<span class=\"svs-cites\"><a href=\"#svs-source-16\" aria-label=\"Source 16\">[16]<\/a><\/span><\/p><a href=\"https:\/\/science.nasa.gov\/mission\/roman-space-telescope\/coronagraph\/\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"svs-button\">Follow the research \u2197<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><\/div><div class=\"svs-card\"><span class=\"svs-video-tag\">ESA and partners \u00b7 LISA<br>Mission in development<\/span><h3>Can we measure a change in spacetime?<\/h3><p>LISA is being developed to track minute distance changes with laser interferometry between three spacecraft. It is a gravitational-wave experiment, not an ordinary camera.<span class=\"svs-cites\"><a href=\"#svs-source-17\" aria-label=\"Source 17\">[17]<\/a><\/span><\/p><a href=\"https:\/\/www.esa.int\/Science_Exploration\/Space_Science\/LISA\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"svs-button\">Follow the research \u2197<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><\/div><div class=\"svs-card\"><span class=\"svs-video-tag\">ESA \u00b7 Plato<br>Mission in preparation<\/span><h3>Why study the star to understand the planet?<\/h3><p>Plato\u2019s 26 cameras are designed to measure brightness variations for planet searches and stellar characterisation. Connect transits to the questions introduced in Chapter 1.<span class=\"svs-cites\"><a href=\"#svs-source-18\" aria-label=\"Source 18\">[18]<\/a><\/span><\/p><a href=\"https:\/\/www.esa.int\/Science_Exploration\/Space_Science\/Plato\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"svs-button\">Follow the research \u2197<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><\/div><div class=\"svs-card\"><span class=\"svs-video-tag\">CERN \u00b7 HiLumi LHC<br>Accelerator upgrade project<\/span><h3>Why collect more collisions?<\/h3><p>Larger collision datasets improve access to rare processes and precision tests. More data still require careful calibration, background models and uncertainty estimates.<span class=\"svs-cites\"><a href=\"#svs-source-19\" aria-label=\"Source 19\">[19]<\/a><\/span><\/p><a href=\"https:\/\/home.cern\/science\/accelerators\/hilumi-lhc\/\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"svs-button\">Follow the research \u2197<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><\/div><div class=\"svs-card\"><span class=\"svs-video-tag\">University of Bern \u00b7 CoCa<br>Instrument development<\/span><h3>Can one camera design inform another mission?<\/h3><p>CoCa, the Comet Camera for Comet Interceptor, builds on experience with CaSSIS while adapting the design to a different encounter. Reuse does not eliminate new requirements.<\/p><a href=\"https:\/\/www.space.unibe.ch\/micro_comin\/content\/instruments\/coca\/index_eng.html\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"svs-button\">Follow the research \u2197<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><\/div><\/div><\/section><section class=\"svs-section\" id=\"svs-quiz\"><span class=\"svs-kicker\">Pause before opening each answer<\/span><h2>Six checks for scientific thinking.<\/h2><p>Write your reason first. No account, score upload or personal information is needed.<\/p><details class=\"svs-detail \"><summary>1. A coronagraph image has a dark central disc. Has material disappeared?<\/summary><div class=\"svs-answer\"><p>No. The instrument deliberately blocks the bright central region. First distinguish the instrument\u2019s effect from a change in the object.<\/p><\/div><\/details><details class=\"svs-detail \"><summary>2. A region appears blue in a Mars image. Is that sufficient evidence of liquid water?<\/summary><div class=\"svs-answer\"><p>No. First read the band selection and processing description. Colour mapping is not a direct chemical test. Compare independent measurements and alternative explanations.<\/p><\/div><\/details><details class=\"svs-detail \"><summary>3. A pulse takes 4 ms to return. Is the range 1,200 km?<\/summary><div class=\"svs-answer\"><p>No. That is the round-trip path length using the rounded classroom speed of light. The one-way range is 600 km.<\/p><\/div><\/details><details class=\"svs-detail \"><summary>4. Equal-charge ions have masses in a ratio of 4:1. Is the flight-time ratio 4:1?<\/summary><div class=\"svs-answer\"><p>Not in the simplified equal-voltage, equal-path model. Flight time scales as the square root of mass-to-charge ratio, giving 2:1.<\/p><\/div><\/details><details class=\"svs-detail \"><summary>5. Do CTAO mirrors collect gamma rays?<\/summary><div class=\"svs-answer\"><p>No. They collect Cherenkov light from atmospheric particle showers. Reconstruction connects that secondary signal to candidate high-energy events.<\/p><\/div><\/details><details class=\"svs-detail \"><summary>6. A coating looks unchanged after a test. Is qualification complete?<\/summary><div class=\"svs-answer\"><p>No. Appearance cannot establish all required optical, electrical, mechanical or environmental properties. Test the relevant functions against predefined criteria.<\/p><\/div><\/details><div class=\"svs-note green\"><strong>Final challenge:<\/strong> choose one instrument. Write four sentences: the question, the signal, the measurement and one limitation. Add a source and identify whether its main picture is an observation, a simulation or an illustration.<\/div><\/section><section class=\"svs-section\" id=\"svs-teachers\"><span class=\"svs-kicker\">For educators and study groups<\/span><h2>One chapter. Two classroom routes.<\/h2><div class=\"svs-quick\"><div><strong>45-minute discovery route<\/strong><span>5 min: image\/evidence warm-up. 10 min: Metis and filter mini-lab. 10 min: BELA calculation. 10 min: short CTAO film excerpt. 10 min: final evidence challenge.<\/span><\/div><div><strong>90-minute investigation route<\/strong><span>Include Mars interpretation, the time-of-flight derivation, the synthetic coating dataset and comparison of two independent sources.<\/span><\/div><div><strong>Assess the reasoning<\/strong><span>Look for units, explicit assumptions, a distinction between observation and interpretation, and a limitation that genuinely matters.<\/span><\/div><\/div><p>Prerequisites: percentages, units and basic ratios. The square-root derivation is optional. All assigned activities use the browser, paper or a safe indoor parallax demonstration. No solar viewing, lasers, vacuum work or electrical experiments are required.<\/p><p><strong>Suggested exit ticket:<\/strong> \u201cI used to think ____. The evidence or model showed ____. I still need to know ____.\u201d<\/p><div class=\"svs-actions svs-js-only\" hidden><button type=\"button\" class=\"svs-button\" id=\"svs-open-answers\">Open all worked answers<\/button><button type=\"button\" class=\"svs-button\" id=\"svs-close-answers\">Close all worked answers<\/button><button type=\"button\" class=\"svs-button\" id=\"svs-print\">Print \/ save this chapter<\/button><\/div><p class=\"svs-mini\">Use your browser\u2019s Print command for a reading copy. Open the worked answers first to include them. For a paper-based activity, use the six questions in Test your understanding and the exit ticket above. A separate printable worksheet is available from the course organiser.<\/p><\/section><section class=\"svs-section\" id=\"svs-glossary\"><span class=\"svs-kicker\">Quick reference<\/span><h2>A small vocabulary for big questions.<\/h2><dl class=\"svs-glossary\"><div><dt>Coronagraph<\/dt><dd>An instrument that suppresses a bright central source to reveal fainter surroundings.<\/dd><\/div><div><dt>Bandpass filter<\/dt><dd>An optical element designed to transmit a chosen wavelength interval.<\/dd><\/div><div><dt>Calibration<\/dt><dd>Determining how recorded signals relate to known reference quantities and conditions.<\/dd><\/div><div><dt>Stereo imaging<\/dt><dd>Using different viewing geometries to recover information about depth and relief.<\/dd><\/div><div><dt>Exosphere<\/dt><dd>A very tenuous outer gas environment in which collisions can be infrequent.<\/dd><\/div><div><dt>Mass-to-charge ratio<\/dt><dd>The particle mass divided by its electric charge; a key variable in mass spectrometry.<\/dd><\/div><div><dt>Cherenkov light<\/dt><dd>Radiation from a charged particle travelling faster than light\u2019s phase velocity in a medium, not faster than light in vacuum.<\/dd><\/div><div><dt>Uncertainty<\/dt><dd>A quantified expression of the limits of a measurement, not simply a mistake.<\/dd><\/div><div><dt>Technology transfer<\/dt><dd>Adapting knowledge or a technology to another use, with new requirements and tests.<\/dd><\/div><div><dt>Assigned \/ false colour<\/dt><dd>A display mapping in which measured bands are represented by chosen visible colours.<\/dd><\/div><\/dl><\/section><section class=\"svs-section\" id=\"svs-sources\"><span class=\"svs-kicker\">Trace the evidence<\/span><h2>Sources, image credits &amp; reading notes.<\/h2><p>Scientific explanations below are based on the linked public institutional sources and instrument-team work. Classroom numbers are explicitly synthetic. Mission plans are not treated as completed results.<\/p><ol class=\"svs-sources\"><li id=\"svs-source-1\"><strong>NASA Science.<\/strong> <a href=\"https:\/\/science.nasa.gov\/ems\/03_behaviors\/\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Wave Behaviors<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><span class=\"svs-source-note\">Background: transmission, reflection, absorption and wavelength-dependent interactions.<\/span><\/li><li id=\"svs-source-2\"><strong>ESA \/ Metis team.<\/strong> <a href=\"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2020\/07\/Solar_Orbiter_s_first_view_of_the_Sun_s_corona\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Solar Orbiter\u2019s first view of the Sun\u2019s corona<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><span class=\"svs-source-note\">Real observations, 2020; display colours are assigned to different wavelength bands.<\/span><\/li><li id=\"svs-source-3\"><strong>University of Bern.<\/strong> <a href=\"https:\/\/www.cassis.unibe.ch\/instrument\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">CaSSIS: instrument and mission<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><span class=\"svs-source-note\">Mission identity and instrument context; distinguish the camera from gas-analysis instruments.<\/span><\/li><li id=\"svs-source-4\"><strong>ESA \/ CaSSIS team.<\/strong> <a href=\"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2019\/09\/Oyama_Crater_Mars\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Oyama Crater, Mars<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><span class=\"svs-source-note\">Processed colour image, 13 June 2019; interpretation is supported by other instruments.<\/span><\/li><li id=\"svs-source-5\"><strong>A. Pommerol and colleagues.<\/strong> <a href=\"https:\/\/arxiv.org\/abs\/2210.04316\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">In-flight radiometric calibration of CaSSIS<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><span class=\"svs-source-note\">Instrument-team paper, 2022. Four filters, framelets and calibration; not a beginner tutorial.<\/span><\/li><li id=\"svs-source-6\"><strong>University of Bern.<\/strong> <a href=\"https:\/\/www.bela.space.unibe.ch\/instrument\/experiment_overview\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">BELA: experiment overview<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><span class=\"svs-source-note\">Laser ranging, return-pulse detection, filtering and conversion from ranges into maps. Not a live mission-status page.<\/span><\/li><li id=\"svs-source-7\"><strong>ESA \/ BepiColombo.<\/strong> <a href=\"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2021\/10\/Hello_Mercury\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Hello Mercury<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><span class=\"svs-source-note\">Monitoring-camera observation on 1 October 2021. Not a BELA measurement.<\/span><\/li><li id=\"svs-source-8\"><strong>University of Bern.<\/strong> <a href=\"https:\/\/www.juice.space.unibe.ch\/instrument\/nim\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">NIM: Neutral and Ion Mass Spectrometer<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><span class=\"svs-source-note\">Ion source, time-of-flight analyser and detector. Our classroom calculator is a simplified model, not a NIM simulator.<\/span><\/li><li id=\"svs-source-9\"><strong>ESA.<\/strong> <a href=\"https:\/\/www.esa.int\/Science_Exploration\/Space_Science\/Juice\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Juice mission<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><span class=\"svs-source-note\">Mission objectives; designed exploration of Jupiter and its icy moons. Mission schedules may change.<\/span><\/li><li id=\"svs-source-10\"><strong>CTAO.<\/strong> <a href=\"https:\/\/www.ctao.org\/emission-to-discovery\/science\/how-ctao-works\/\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">How CTAO Works<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><span class=\"svs-source-note\">Air showers and Cherenkov-light detection. No claim that telescope mirrors reflect gamma rays.<\/span><\/li><li id=\"svs-source-11\"><strong>CERN.<\/strong> <a href=\"https:\/\/home.web.cern.ch\/news\/news\/experiments\/upgrading-lhcb-sub-detectors-hl-lhc\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Upgrading the LHCb sub-detectors for the HL-LHC<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><span class=\"svs-source-note\">RICH photon detection and timing; a different use of the same physical phenomenon.<\/span><\/li><li id=\"svs-source-12\"><strong>NASA Technical Reports Server.<\/strong> <a href=\"https:\/\/ntrs.nasa.gov\/citations\/20050176383\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Transparent, Conductive Coatings Developed for Arc-Proof Solar Arrays<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><span class=\"svs-source-note\">Historical research record, 1996. Example of optical and electrical requirements, not a TFP attribution.<\/span><\/li><li id=\"svs-source-13\"><strong>NASA Science.<\/strong> <a href=\"https:\/\/science.nasa.gov\/ems\/07_infraredwaves\/\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Infrared Waves<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><span class=\"svs-source-note\">Infrared radiation and thermal imaging. Not all infrared observation is thermography.<\/span><\/li><li id=\"svs-source-14\"><strong>ESA \/ JANUS team.<\/strong> <a href=\"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2024\/08\/Juice_JANUS_view_of_Earth\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Juice JANUS view of Earth<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><span class=\"svs-source-note\">Image of Luzon, 20 August 2024, acquired during instrument-performance evaluation.<\/span><\/li><li id=\"svs-source-15\"><strong>Scuola Normale Superiore.<\/strong> <a href=\"https:\/\/normalenews.sns.it\/individuata-una-delle-piu-antiche-galassie-morte-soffocata-dal-buco-nero-al-suo-interno\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Pablo\u2019s Galaxy: research with Webb and ALMA<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><span class=\"svs-source-note\">Research reported 14 January 2026, involving the Normale and a Cambridge-led collaboration.<\/span><\/li><li id=\"svs-source-16\"><strong>NASA Science.<\/strong> <a href=\"https:\/\/science.nasa.gov\/mission\/roman-space-telescope\/coronagraph\/\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Roman Coronagraph<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><span class=\"svs-source-note\">Masks and deformable mirrors for starlight suppression; a technology-demonstration objective, not a claim of detected life.<\/span><\/li><li id=\"svs-source-17\"><strong>ESA.<\/strong> <a href=\"https:\/\/www.esa.int\/Science_Exploration\/Space_Science\/LISA\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">LISA<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><span class=\"svs-source-note\">Mission in development; laser interferometry for gravitational-wave measurements.<\/span><\/li><li id=\"svs-source-18\"><strong>ESA.<\/strong> <a href=\"https:\/\/www.esa.int\/Science_Exploration\/Space_Science\/Plato\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Plato<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><span class=\"svs-source-note\">Mission in preparation; 26 cameras and measurements of stellar brightness variations.<\/span><\/li><li id=\"svs-source-19\"><strong>CERN.<\/strong> <a href=\"https:\/\/home.cern\/science\/accelerators\/hilumi-lhc\/\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">HiLumi LHC<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><span class=\"svs-source-note\">Upgrade project and why larger datasets help investigate rare processes.<\/span><\/li><li id=\"svs-source-20\"><strong>NASA Science.<\/strong> <a href=\"https:\/\/science.nasa.gov\/eclipses\/safety\/\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Eclipse Viewing Safety<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><span class=\"svs-source-note\">Safety source. No solar observation or laser experiment is assigned in this chapter.<\/span><\/li><li id=\"svs-source-21\"><strong>University of Bern.<\/strong> <a href=\"https:\/\/www.cassis.unibe.ch\/\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">CaSSIS images and observation browser<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><span class=\"svs-source-note\">Entry point for released images, films and observational data. The observation browser requires JavaScript.<\/span><\/li><li id=\"svs-source-22\"><strong>ESA.<\/strong> <a href=\"https:\/\/www.esa.int\/ESA_Multimedia\/Images\/2022\/12\/Planetary_Science_Archive_maximising_science_from_our_missions\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">Planetary Science Archive: maximising science from our missions<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a><span class=\"svs-source-note\">Why calibrated data, documentation and archives matter.<\/span><\/li><\/ol><div id=\"svs-archive\" class=\"svs-note\"><strong>[A] Author-supplied historical material.<\/strong> <em>TFP VISION<\/em>, brochure, pages 2\u20133 and 18: intended applications, visible\/infrared concept and limitations of declared specifications. The document is not redistributed here. The accompanying technology-transfer account is the engineer\u2019s testimony, not independent verification of a mission supply. Other supplied corporate documents are not used as authority for mission identities.<\/div>\n<p class=\"svs-mini\">CoCa further reading: <a href=\"https:\/\/www.space.unibe.ch\/micro_comin\/content\/instruments\/coca\/index_eng.html\" target=\"_blank\" rel=\"noopener noreferrer\" class=\"\">University of Bern: Comet Camera<span class=\"svs-sr\"> (opens in a new tab)<\/span><\/a>.<\/p>\n<p class=\"svs-mini\"><strong>Image provenance:<\/strong> the credit, original record and licence are attached to each image. Images are linked from their official hosts without colour alteration or relabelling. Artist\u2019s impressions are marked. Remote hosting can change; a text link remains beside every figure. For educational\/editorial use only where required by the licence; do not reuse these agency images in paid advertising without checking the relevant terms.<\/p>\n<p class=\"svs-mini\"><strong>Independence:<\/strong> Stadia is an independent educational initiative. No endorsement, partnership, accredited course or review by the institutions mentioned is implied.<\/p><\/section>\n<section class=\"svs-share\" aria-labelledby=\"svs-share-title\"><span class=\"svs-kicker\">Bring one question to someone else<\/span><h2 id=\"svs-share-title\">What would you measure?<\/h2><p>Share this chapter with a class, an astronomy club or a curious friend. Choose one question and compare your reasoning before opening the answer.<\/p><div class=\"svs-actions\"><a class=\"svs-button primary\" href=\"https:\/\/stadiaorg.com\/astronomy-science\/\">Back to Astronomy &amp; Science \u2192<\/a><button class=\"svs-button svs-js-only\" hidden type=\"button\" id=\"svs-copy\">Copy chapter link<\/button><a class=\"svs-button\" href=\"mailto:?subject=Stadia%20Science%20%7C%20Eyes%20and%20senses%20of%20space%20missions&amp;body=Explore%20the%20chapter%20and%20try%20a%20mini-lab%3A%20https%3A%2F%2Fstadiaorg.com%2Fastronomy-science%2Fspace-instruments%2F\">Share by email<\/a><\/div><p id=\"svs-copy-status\" class=\"svs-local-status\" aria-live=\"polite\"><\/p><label for=\"svs-copy-fallback\" class=\"svs-sr\">Chapter link to copy<\/label><input id=\"svs-copy-fallback\" class=\"svs-copy-field\" type=\"text\" readonly hidden value=\"https:\/\/stadiaorg.com\/astronomy-science\/space-instruments\/\"><\/section>\n<footer class=\"svs-footer\"><p><strong>Stadia Science \u00b7 Chapter 2 \u00b7 v1.0.<\/strong> Sources reviewed 27 September 2026. 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How do we turn the invisible into evidence? Block a star. Read a landscape. Time a pulse. Sort particles. Follow the instrument from a scientific question to a measurement you can trust. Start the journey [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":1964,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-1975","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/stadiaorg.com\/es\/wp-json\/wp\/v2\/pages\/1975","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/stadiaorg.com\/es\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/stadiaorg.com\/es\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/stadiaorg.com\/es\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/stadiaorg.com\/es\/wp-json\/wp\/v2\/comments?post=1975"}],"version-history":[{"count":4,"href":"https:\/\/stadiaorg.com\/es\/wp-json\/wp\/v2\/pages\/1975\/revisions"}],"predecessor-version":[{"id":1979,"href":"https:\/\/stadiaorg.com\/es\/wp-json\/wp\/v2\/pages\/1975\/revisions\/1979"}],"up":[{"embeddable":true,"href":"https:\/\/stadiaorg.com\/es\/wp-json\/wp\/v2\/pages\/1964"}],"wp:attachment":[{"href":"https:\/\/stadiaorg.com\/es\/wp-json\/wp\/v2\/media?parent=1975"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}