The visible universe is unimaginably huge but there

is one image that can give us a small glimpse at its

awe-inspiring scale, and that is the

Hubble Deep Field Image.

[Fanfare jingle]

[Explosion sound and electric guitar riff]

In 1995, astronomers wanted to see what would happen

if they pointed the new Hubble Space Telescope at an

area of the sky that was nearly devoid of all stars.

They let it soak up light for over 140 hours over a

span of 10 days and what they saw was nothing short of spectacular.

This, is the Hubble Deep Field Image. [Orchestral music building]

What you're seeing here is not just a few stars,

nebulas and star clusters but each and every dot

and fuzzy patch you are seeing is an entire galaxy,

each containing around 100 billion stars!

To get an idea of how many stars are in each one of

those galaxies, imagine an Olympic-sized swimming

pool and fill it with standard 1.5cm marbles.

If my calculations are correct (taking into account

the max density of close-packed spheres),

it would fit about 1 billion marbles.

That would mean we'd need 100 Olympic swimming

pools full of marbles to equal the number of stars in an average galaxy!

In a similar, more recent capture called the Hubble

ULTRA Deep Field image, we can see around 10,000

galaxies, each with around 100 billion stars.

Pretty cool right? But you haven't heard the most amazing thing yet!

This image is not the entire night sky - far from it!

This is only a tiny fraction of the sky -

one 13 millionth to be exact!

Look at the size of the D on the front of an

American penny then hold the penny up to the sky at arm's length.

The area of sky that the Ultra Deep Field image takes up

is roughly contained entirely in that tiny "D".

The Hubble Deep Field Images allow us to peer deeper

into space AND time than we have ever seen before.

I say deeper into time because some of these objects

are so far away, the light coming from them has taken

up to 13 billion years to get to us so we're seeing

them as they looked less than a billion years after

the Big Bang, long before the Earth was even formed.

Some of these distant objects are called quasars

which are the most powerful and luminous objects in the universe.

Even though they're only about the size of our solar

system, they emit up to 1000 times more energy than

the ENTIRE Milky Way galaxy, which contains between 200 and 400 billion stars.

They're made up of supermassive black holes that are

consuming so much material, that they shoot giant

jets of particles traveling at nearly the speed of light,

thousands of light years into space!

Yeah, quasars are pretty awesome.

Looking at this image is a humbling experience,

but to me, it just shows how amazing our universe is

and how much there is left for us to explore.

It's almost unfathomable that we could be the only life

in this vast universe.

Peer into this image long enough and you'll start

to imagine what awe-inspiring wonders could be

hiding in those distant galaxies full of billions

of planets. Scientists are learning more about our

universe and our local galaxy every day.

Just imagine what they might find next!

You can download a high resolution copy of the

Hubble Ultra Deep Field image here or on the link

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science videos and also check out some of our

educational videos for preschool kids.

Thanks so much for watching, and see you next time!

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