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  • Cameras are the foundational instruments of every space telescope.

  • Their eyes have allowed us to see the 'unseeable,'

  • shedding light on how planets are born

  • and even the approximate age of the universe.

  • And now, a new, groundbreakingly sensitive camera is pushing the limits of what we can detect even further

  • to include the chemical signatures of alien life.

  • When the James Webb Space Telescope finally launches,

  • its suite of next-generation imaging systems will give us views of the universe we've never seen before.

  • But there's one important instrument that James Webb doesn't have

  • one that could unlock the secret recipe of extraterrestrial life.

  • That's where this new camera comes in.

  • Developed by a team at NIST, it is composed of sensors so sensitive

  • that they count single particles of light, or photons, to generate an image.

  • And it was developed partially in the hopes of flying it on NASA's next, next-generation telescope: Origins.

  • I think what we can offer with our detector technology,

  • is that because they are superconducting, they're more sensitive and they also have lower noise.

  • All cameras do the same thing: analyze light

  • but different kinds of systems can be used to see different things.

  • Wide-field cameras look at objects in various wavelengths,

  • and are actually what helped us take the first image ever of an exoplanet in visible light.

  • But to find out details about an exoplanet, like its chemical makeup and potential to harbor life,

  • a spectrograph is used.

  • Similar to how a prism splits light into a rainbow,

  • this instrument breaks down light within the EM spectrum into its component parts.

  • By doing so, it allows us to study any object that absorbs light and identify its unique characteristics.

  • An interferometer can then come in to make precise measurements

  • of the object's relative position and brightness.

  • What's important to note is that every one of these cameras is equipped with sensors,

  • which translate their light measurements into electrical signals.

  • And the more sensitive they are, the better.

  • That's why NIST's new camera is so exciting

  • it has over 1,000 sensors and uses materials that can achieve superconductivity

  • when they reach a cold enough temperature.

  • This transition temperature is the point at which a material no longer has any resistance.

  • With future space telescopes, NASA is always trying to figure out better ways

  • to improve the signal and reduce the noise.

  • Especially for things like exoplanet spectroscopy, which is the application that we're really targeting.

  • Remember that a spectrograph can identify the characteristics of any object that absorbs light?

  • With more sensitive detectors, it can pick up on a broader range of wavelengths more easily.

  • This increases its chance of spotting signs of alien life.

  • Basically, the idea is that every molecule or chemical element has a very unique spectral signature.

  • The signals of interest lie between wavelengths of about 2 microns out to 20 microns in wavelength.

  • If we're going to look at chemical signs of life on other planets or even on the Earth,

  • all of those elements have absorption lines within that range of wavelengths.

  • Elements like oxygen, water vapor, and gases like CO2 lie within this range,

  • and are just some of the signs of life that we're on the lookout for.

  • But this range of wavelengths is extremely difficult to work in,

  • because the photons interacting with these elements don't have much energy and are hard to detect.

  • To overcome this obstacle, NIST had to think small.

  • As soon as a photon meets the detector array, it absorbs into its nanometer scale wires.

  • This encounter generates lots of heat, disrupting the superconductivity in a tiny region of the wire

  • for a flash of an instant, creating a pulse.

  • Because each pulse conveys information, being able to sense the smallest amounts of light energy

  • has the potential to yield huge rewards.

  • By stitching together these pulses of information,

  • we could not only gather many more clean signals potentially indicating extraterrestrial life,

  • but perhaps even detect the interactions of elusive dark matter with other particles out in space.

  • But before we get ahead of ourselves, the NIST team still has a way to go

  • to realize the dreams of their high performance camera.

  • This is basically a very first, rudimentary demonstration that we've done, creating this array.

  • There's still a lot of work to do to optimize it.

  • If you want to learn even more about all the ways that we're searching for alien life

  • and the planets that could support it

  • then check out our video on NASA's exoplanet hunter here.

  • Let us know in the comments below if you'd like us to cover more stories about how we're searching for aliens,

  • and make sure to subscribe to Seeker for all your space news.

  • Thanks for watching, and I'll see you next time.

Cameras are the foundational instruments of every space telescope.

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這款下一代相機旨在捕捉外星生命。 (This Next Generation Camera Aims To Capture Alien Life)

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    林宜悉 發佈於 2021 年 01 月 14 日
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