On rare nights with clear visibility over powerful distant thunderstorms,
you might be able to see and capture red sprites.
Sprites are large-scale electrical discharges occurring high above
thunderstorms in the upper atmosphere
Bam. There's a sprite. Bam bam bam! They come in clusters.
They are massive events
Wow! Wowowow.
Sometimes 50 kilometers tall by 50 kilometers wide.
They belong to a mysterious and colorful group of phenomena
called transient luminous events or TLEs.
Other TLEs include halos, Elves,
secondary jets, blue starters, blue jets, and the magnificent gigantic jets.
But what exactly are these transient luminous events and how do they form?
In 2019 I teamed up with one of the most successful TLE photographers in the world,
Paul Smith.
Our objective was to simultaneously document TLEs from different locations
to help us understand and capture them better.
Boom! Whoa whoa whoa. Yep. Right there!
We didn't know what we would find if anything,
nice falling star
but we never expected to discover a new TLE.
Greeeeeen!
In this video Paul and I will summarize
current scientific understanding of red sprites
as well as showcasing some of the most rare
and amazing captures ever recorded.
Visual reports of transient luminous events date back several centuries.
It wasn't until 1989 that the first ones were accidentally caught on camera.
Years after discovery they were named
sprites for their spirit-like nature
In a recent video we showed how one lightning flash can abruptly change the
electric field triggering a secondary flash in a sort
of domino effect.
Sprites are also initiated by a large electric field change
that occurs during a massive horizontally extensive lightning strike far below.
These parent flashes transfer huge amounts of charge and are almost
always positive in polarity meaning that the earth rapidly gains a
net positive charge from the strike.
But pools of positive charge near the
tops of thunderstorm complexes also change
abruptly gaining negative charge.
This suddenly creates a powerful electric field
between the tops of thunderstorms and a high concentration of positively
charged ions existing 100 kilometers or so up into the lower Ionosphere.
it's this new imbalance that can initiate a sprite.
On June 22, 2019 Paul was documenting sprite activity over a thunderstorm
while i simultaneously documented their apparent lighting activity
under the thunderstorm.
Boom! whoa whoa whoa. Yep, right there.
Did you get a sprite?
Two dancing sprites.
Oh no way?!?!
yeah man!
Boom. See it?
That wasn't a big sprite through, Just a little column.
Boom. Yes!
Awesome!
You can sprite now...
oh oh yeah gotcha!
With every horizontally extensive positive ground flash
I observed under the storm, Paul observed a sprite
above the storm.
On occasion a cloud flash will have one end of the leader exit the upper extent
of the thunderstorm and propagate toward the upper atmosphere
The rarefied air and low pressure of the upper atmosphere
leads to a visible transformation in the leader as the ionization travels upward.
This is how blue jets form as well as the magnificent
gigantic jet.
Sprites are often incorrectly referred to as upper atmospheric lightning,
but lightning temperatures are much much hotter.
Sprites are considered a cool plasma phenomenon.
The physics that causes sprites to briefly glow red
is much like the process that causes the auroras.
When energy in the form of speeding charged particles collide with atoms in
our atmosphere, that energy is transferred causing the atoms to become excited.
As they calm down, they can release some
of that energy back into the atmosphere in the form of light
Each element has a unique emission spectrum that acts as a fingerprint
identifying the guilty culprit.
In other words we can identify what
element is being excited by the color of its light emissions.
Just like you could with a bunsen burner in your grade school science lab
assuming you weren't raised in a barn.
Oxygen tends to give off mostly green
light when excited and nitrogen reds and blues depending on the
atmospheric pressure and other physics.
The energy particles that cause the auroras to glow come from the sun
and arrive in storms of solar wind we call geomagnetic storms.
With sprites the energy is generated by the powerful electric field
between the thunderstorm and upper atmosphere.
Auroras occur way higher than sprites, up around 100 to 500 kilometers in altitude
where the atmosphere is mostly molecular oxygen
As mentioned earlier the excitation of oxygen emits green light
and that's why the auroras are mostly green.
But in some really strong auroral events, you can see pinkish fringes along the
bottom edge of the green aurora, and that's usually where the high energy
particles from the sun have penetrated way down in our atmosphere
where there's an increasingly higher percentage of nitrogen,
right around the 100 km altitude.
Right around the top edge where sprites reach.
Sprites occur around 40 to 100 km and at these altitudes
the atmosphere is mostly nitrogen. Remember earlier that the excitation of
nitrogen emits blues and reds.
Sprite!
At the atmospheric pressure sprites occur
nitrogen excites red,
but as the pressure increases the closer you get to earth,
nitrogen excites more in the blues.
Sometimes a large sprite event can trigger a second TLE.
We call these secondary jets.
Secondary jets become visible near the tops of thunderstorms
where nitrogen excites in the blues,
and extend upward to altitudes where nitrogen excites more red.
in a photograph of a sprite and secondary jet event you can see the
gradual transitioning from blues to reds as the pressure quickly decreases in altitude.
Ooo, Yeah! Sprites! hahah... Yay!
On May 25, 2019 I was documenting a vibrant sprite storm over Oklahoma
and captured something i've never seen or heard of,
It's spreading like crazy. This is so awesome.
After two large sprite events a mysterious green afterglow appeared.
It seemed as if the sprite had triggered a small aurora.
Early that next morning I called Paul to discuss the strange captures.
He was the first to agree it was something new and hypothesized that it
was likely oxygen being excited. For the next few weeks Paul and I shared
this strange discovery with scientists as well as the public in various weather threads
trying to ferret out an explanation.
Nobody had ever heard of this before.
Paul scoured through his extensive archives and found a similar event
and storm chaser Scott Currens did as well, but both examples were too low
resolution and too faint to give much support.
Many people argued as a camera sensor artifact rather than a natural occurring
phenomenon. Weeks later though paul silenced the
skepticism with several deal sealer captures.
The night of September 24, 2019 there was some big storms over
central Kansas. I was getting a few sprites earlier in the night
and then all of a sudden with this really big bright lightning strike
I captured this monstrous sprite... Just one of the best
sprites i've ever seen in my life. it's got all of the colors that can be
involved in TLEs ranging from the pinks down to the purples in the lower
atmosphere with the reds at the top, and then upon closer review I could see
that I got a really good example of these green tops of the sprite that
I'd seen Hank capture before. I was pretty excited about that and then
just an hour or so later I also caught this
set of dancing sprites where sprites were firing in
succession. The last sprite in that series was really strong
and left a really really good example of the green afterglow when it was done.
So I was really excited that night to capture some some of my own
high contrast green afterglow events. Not too much longer after just a month later
I was shooting over towards Arkansas and I started getting
really strong sprites and a couple of these
i was also getting the green afterglow.
Wow! and green!
So this is when I started getting really excited thinking well Hank's caught
something here and now i'm getting them too this is
something that's really happening out there.
I decided to go online and look through some archives of other people's captures
as you can see in some of these we've got these really big powerful sprites
with what looks like a green tinge on top.
So maybe these sprites were seen with the green tops are stronger sprites
where the oxygen is getting excited at a higher level and the glow from that
oxygen is lasting longer than the glow from the nitrogen which would be red.
Keeping in the theme of sprites, trolls and elves, we are referring to these
green emissions from excited oxygen and sprite tops
as ghosts.
I'd like to send a colossal thanks out to Paul Smith for sharing his amazing
captures and knowledge with us. Yeah thanks a lot Hank man thanks a lot
for having me i'm just really pumped to have somebody that's excited about this
as i am and i can't wait to see what we catch
it going forward. Yeah man it's extremely rewarding that
even in this age if there's nothing new under the sun
ordinary people can still go out and discover something no one has ever
documented before. Thanks for watching everyone! Be sure and
check out Paul's youtube channel to see all the TLEs and whatnot he captures
among the stars. 'til next time friends, happy trails!