Airglow: Why The Night Sky Is Really Green

If you look closely enough, you’ll see the night sky is actually a little green. SciShow Space explains the science behind the phenomenon known as airglow.

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[ABitOfTheUniverse]

1:53 2:27
Color *Wavelength* Frequency Photon energy
violet 380–450 nm 668–789 THz 2.75–3.26 eV
*blue 450–495 nm* 606–668 THz 2.50–2.75 eV
*green 495–570 nm* 526–606 THz 2.17–2.50 eV
yellow 570–590 nm 508–526 THz 2.10–2.17 eV
orange 590–620 nm 484–508 THz 2.00–2.10 eV
red 620–750 nm 400–484 THz 1.60–2.00 eV

[Zerepzerreitug]

So lonely oxygen atoms in the upper limits of the atmosphere fail miserably to find a partner, and after much search and lots of disappointment, they give up and use their final resource to release all the "excitement" energy they held until then. A brief, wimpy, lonely discharge of a photon.

You call it Airglow. I'll start calling it the _Oxygen Fapping Zone_, or OFZ as it will be named in future scientific literature.

[dresinss]

Bump.  Lynda.com is not just a sponsor, it is the BEST place to learn certain things.  I'm real, it's dark and not exactly cold in Boise right now, and Lynda is the BEST place to find tutorials, if they have a tutorial for it.

[gethinjones]

Great stuff guys, really clearly explained. Keep getting smarter!

[RandyKnapp]

This was awesome. I actually had no idea this phenomenon existed!

[ErgoCogita]

At 3:07 you said _"...from their less excited state..."_ when I think you meant *from their excited state to their least excited state* .

Yes?

[IstasPumaNevada]

Interesting and well put. Thank you for a good video, as usual. :)

[lfrohling]

This was the first time he made me laugh :) keep up the good work- enjoy what u do and we will enjoy watching u :))

[Slattery]

This guy has a soothing voice - he needs to do trailers

[jellpuddng]

thank you so much for referencing quantum physics!

[AlayShah]

Could you guys do a video (maybe even a series) on how to use a telescope and watch the night sky?

[bluemoon]

I have tetrachromacy (four color cones in the eyes. basically extreme opposite of color blindness) and can often see different colors where no one else can and they look at me like I'm crazy and I look at them like they're blind. Nice to know that I'm actually seeing the colors along with the typical blue night sky, instead of being crazy.

[Beer_Dad]

I have to say I've been an amateur astronomer for 25 years, observed from some very dark sky sites, and never noticed the sky was green at all... perhaps my dark-adapted eyes are just not sensitive enough to colour to see it.

[KarbineKyle]

You should talk about X-ray fluorescence (XRF) and/or gamma ray spectroscopy (GRS) next, or scintillation detectors, please.

[ruawhitepaw]

What about nitrogen molecules? I know those take a lot of energy to break apart, but do they do anything like this at all?

[nickhardacre]

Hey man, you are getting really good at this who presenter game :)

[vzangel]

At the beginning you say: “The night sky is full of all sorts of things, the moon, stars, some planets, sweeping swathes of the Milky Way, but if you took away all off that stuff, you think the sky would be just dark”, but later you mention that the airglow is caused by the sun, and AFAIK the Sun is a star, so you don’t answer your premise of what happens if you took away all the stars in the sky.

[nobodycomments]

When will you all cover the successful Orion mission. Truly something to look to for promise in interplanetary travel.

[ieuanhunt]

Dude I don't fully understand what you are saying but I don't care it sounds awesome

[xevira]

Green is a higher wavelength than blue, not lower.  I think you mean frequency.