2b:null 2c:["$","title",null,{"children":"Transit of Mercury (2019) | Jeremy Ashkenas | Observable"}] 31:[] 2f:{"id":"1a67fa9660266e88","slug":"transit-of-mercurcy-2019","title":"Transit of Mercury (2019)","thumbnail":"664ff637d5e7f729a2c6892744b79c98b668a8b4494622eee06ecaf1f5d872d2","access_level":"public","create_time":"$D2019-11-11T17:31:13.090Z","update_time":"$D2019-11-11T20:25:45.855Z","view_time":null,"first_public_time":"$D2019-11-11T17:38:00.283Z","fork":false,"stars":4,"starred":false,"owner":{"type":"team","id":"172cc08ef8a18a4b","login":"jashkenas","name":"Jeremy Ashkenas","avatar_url":"https://avatars-next.observableusercontent.com/fa1903f8171d4621ef49de28e0ff1fb965960ec87df175d8b543c4b09508b45b","tier":"starter_2024"},"version":112,"publish_version":112,"role":null,"authored":false,"authors":[{"type":"individual","id":"783616ba9fb55f5d","login":"jashkenas","name":"Jeremy Ashkenas","avatar_url":"https://avatars-next.observableusercontent.com/fa1903f8171d4621ef49de28e0ff1fb965960ec87df175d8b543c4b09508b45b","tier":null}],"members":[{"type":"individual","id":"783616ba9fb55f5d","login":"jashkenas","name":"Jeremy Ashkenas","avatar_url":"https://avatars-next.observableusercontent.com/fa1903f8171d4621ef49de28e0ff1fb965960ec87df175d8b543c4b09508b45b","tier":null,"role":"editor"}],"comments":[],"custom_thumbnail":true,"trashed":false,"lapsed":null,"subscribed":null,"forks":3,"collection":null,"type":"notebook","body":{"title":"Transit of Mercury (2019)","cells":[{"id":0,"value":"md`# Transit of Mercury (2019)\n\n*See also: [Full disk](https://observablehq.com/@jashkenas/transit-of-mercury-full-disk-2019)*\n\n*Source: [NASA](https://mercurytransit.gsfc.nasa.gov/)*`","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":13,"value":"viewof frame = {\n const form = html``;\n const speed = 83;\n function tick() {\n form.i.value = (form.i.valueAsNumber + 1) % frames.length;\n form.i.dispatchEvent(new CustomEvent(\"input\", { bubbles: true }));\n }\n let interval = setInterval(tick, speed);\n form.b.onclick = () => {\n if (interval) {\n form.b.textContent = \"Play\";\n interval = clearInterval(interval);\n } else {\n form.b.textContent = \"Pause\";\n interval = setInterval(tick, speed);\n }\n };\n form.i.oninput = event => {\n if (!(event instanceof CustomEvent) && interval) form.b.click();\n form.value = form.o.value = form.i.valueAsNumber;\n };\n form.value = form.o.value = 0;\n invalidation.then(() => clearInterval(interval));\n return form;\n}","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":23,"value":"transit = html`

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