, but this code // executes before the first paint, when

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is not yet present. The // classes are added to so styling immediately reflects the current // toolbar state. The classes are removed after the toolbar completes // initialization. const classesToAdd = ['toolbar-loading', 'toolbar-anti-flicker']; if (toolbarState) { const { orientation, hasActiveTab, isFixed, activeTray, activeTabId, isOriented, userButtonMinWidth } = toolbarState; classesToAdd.push( orientation ? `toolbar-` + orientation + `` : 'toolbar-horizontal', ); if (hasActiveTab !== false) { classesToAdd.push('toolbar-tray-open'); } if (isFixed) { classesToAdd.push('toolbar-fixed'); } if (isOriented) { classesToAdd.push('toolbar-oriented'); } if (activeTray) { // These styles are added so the active tab/tray styles are present // immediately instead of "flickering" on as the toolbar initializes. In // instances where a tray is lazy loaded, these styles facilitate the // lazy loaded tray appearing gracefully and without reflow. const styleContent = ` .toolbar-loading #` + activeTabId + ` { background-image: linear-gradient(rgba(255, 255, 255, 0.25) 20%, transparent 200%); } .toolbar-loading #` + activeTabId + `-tray { display: block; box-shadow: -1px 0 5px 2px rgb(0 0 0 / 33%); border-right: 1px solid #aaa; background-color: #f5f5f5; z-index: 0; } .toolbar-loading.toolbar-vertical.toolbar-tray-open #` + activeTabId + `-tray { width: 15rem; height: 100vh; } .toolbar-loading.toolbar-horizontal :not(#` + activeTray + `) > .toolbar-lining {opacity: 0}`; const style = document.createElement('style'); style.textContent = styleContent; style.setAttribute('data-toolbar-anti-flicker-loading', true); document.querySelector('head').appendChild(style); if (userButtonMinWidth) { const userButtonStyle = document.createElement('style'); userButtonStyle.textContent = `#toolbar-item-user {min-width: ` + userButtonMinWidth +`px;}` document.querySelector('head').appendChild(userButtonStyle); } } } document.querySelector('html').classList.add(...classesToAdd); })(); Looking at the sun - News & Stories | 黄大仙高手论坛

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Looking at the sun

Mon, Apr 01, 2019

Tuesday, May 10, 1994. Jonathan Niehof 鈥00 distinctly remembers that day, specifically its partial solar eclipse. 鈥淚 brought filters and pinhole cameras to school so other kids could watch it with me,鈥 he said.

He had no idea that 25 years later he鈥檇 still be helping people look at the sun.

Niehof is part of a team that鈥檚 helping send NASA鈥檚 Parker Solar Probe closer to the sun than any human-made object has ever come. Launched in August, the spacecraft made its first flyby in early November. In 24 orbits over seven years, it will eventually come within 3.7 million miles of the surface. That鈥檚 one-eighth of the distance between the sun and Mercury, its nearest planet.

鈥淭his is real discovery stuff,鈥 Niehof said. 鈥淭he data is so unprecedented, we don鈥檛 even know what to expect.鈥

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Parker Solar Probe is designed to study three big questions in solar physics. Niehof, a research scientist at the University of New Hampshire Space Science Center (UNSSC), is working on the third: How do some of the sun鈥檚 most energetic particles rocket away from the sun at more than half the speed of light? UNSSC is operations headquarters for two instruments onboard the probe that measure high-energy particles.

It鈥檚 that last question that engrosses Niehof. The UNSCC is the operations headquarters for two instruments on board the probe that measure high-energy particles. 鈥淭hese energetic particles get a good acceleration kick right out of the sun,鈥 Niehof explained. 鈥淏ut as they move out through the solar wind, they鈥檙e changed. We want to work out the physics of the change all the way from the sun to the Earth. Then, if we see something on the surface of the sun, we鈥檒l be able to predict what the radiation environment will be like on Earth a few days later. Because these particles can cause severe radiation damage to spacecraft, and the magnetic field carried in the solar wind can disrupt satellite electronics.鈥

A physicist and a computer scientist, Niehof鈥檚 specific role in this mission is to take the raw, compressed data collected by the probe鈥檚 energetic particle instruments and refine them into a form that scientists can use. He expects the first download of probe data in late April.

鈥淏aseline, my job is to make sure this data is available for everyone鈥攊ncluding, ultimately, the public. But I鈥檓 definitely part of the everyone who wants to sink my teeth into it!鈥