How big is our Universe? | BBC Ideas

Summary

This video pays homage to the iconic 1977 film 'Powers of Ten' by Charles and Ray Eames, taking viewers on a journey through the scale of the Universe. Starting with a picnic scene in Sicily, the video zooms out exponentially, showcasing distances from meters to light years. It explores humanity’s place in the cosmos, the vastness of space, interstellar travel, and the observable Universe, up to the limits of what we can perceive today. The journey highlights key discoveries in astrophysics, leaving us to wonder what future explorations may reveal about the Universe and beyond.

Takeaways

• 🌌 The vastness of the universe is a complex concept that astrophysicists continue to explore and attempt to explain.
• 🎥 In 1977, Charles and Ray Eames created 'Powers of Ten,' a groundbreaking film that visualized the universe's scale from a picnic blanket to the edge of the known universe.
• 🌍 Starting from a 1-meter scene, we zoom out exponentially, showcasing the vast distances and scales of the universe.
• 🛰️ Human activity becomes indistinguishable as we move beyond Earth's atmosphere, revealing the planet and its surroundings from a cosmic perspective.
• 🌕 At 10 to the 8 meters, we reach the distance light travels from the Moon to Earth, illustrating the concept of the speed of light and the vastness of space.
• ☀️ The journey takes us through the solar system, highlighting the orbits of planets, including the gas giants and dwarf planets like Pluto.
• 🚀 The Voyager 1 and 2 spacecraft, launched in 1977, have now traveled into interstellar space, marking humanity's farthest reach.
• 🌌 As we move further out, we see the Milky Way galaxy, a vast collection of 100 to 400 billion stars, with a supermassive black hole at its center.
• 🪐 The local group of galaxies, including the Magellanic Clouds and other galaxies, expands our view to a larger cosmic structure.
• 🌌 At the current limits of our vision, we see clusters of galaxies and the cosmic microwave background radiation, which marks the universe's beginnings.
• ❓ Beyond the observable universe, there are questions about the nature of space, the potential existence of more universes, and how our understanding will evolve by 2077.

Q & A

What is the primary theme of the video script?

The primary theme is an exploration of the vastness of the Universe, using the concept of scaling distances exponentially, similar to the 'Powers of Ten' film created by Charles and Ray Eames in 1977.

What is the significance of the 'Powers of Ten' film mentioned in the script?

'Powers of Ten' is a groundbreaking film by Charles and Ray Eames that took viewers on a journey through scale, from a small picnic on Earth to the edge of the known Universe, explaining scientific concepts in an elegant and accessible way.

How does the script's journey through space begin, and what is the method of scaling?

The journey begins with a picnic scene on the island of Sicily, viewed from one meter away. Every 10 seconds, the view scales 10 times farther, expanding the scene exponentially into the distance.

At what distance does the human impact on Earth become indistinguishable in the script?

Human impact becomes indistinguishable at around 10,000 meters (10^4 meters), where the highest altitude flown by supersonic planes is reached.

When does the script mention we leave Earth's atmosphere and what do we see at this point?

At 1 million meters (10^6 meters), we leave Earth's atmosphere and see the whole planet from space, described as a 'jewel.'

What significant milestone is reached at 10 to the 13 meters?

At 10 to the 13 meters, we exit the solar system. This is also the distance the Voyager 1 spacecraft traveled in 2012, becoming the first human-made object to leave the solar system.

What does the script mention about the Alpha Centauri system?

Alpha Centauri, located at a distance of 10 to the 16 meters (one light year), is mentioned as our closest stellar neighbor, consisting of three stars with orbiting planets.

What is significant about the Milky Way Galaxy as mentioned in the script?

The Milky Way contains between 100 and 400 billion stars and a supermassive black hole, Sagittarius A*, at its center. It is described as a flat spiral with many stars and nebulae, where new stars are born.

What is the cosmic microwave background radiation, and why is it important in the script?

The cosmic microwave background radiation is the remnant light from the Big Bang, emitted around 380,000 years after the event. It forms the current limit of our vision and reveals early matter clumping together to form galaxies.

What unanswered questions about the Universe does the script raise towards the end?

The script raises questions about whether there is more universe beyond what we can see, if the universe is still expanding, or if other universes with different physical properties exist. These are topics of ongoing debate.

Outlines

00:00

🚀 A Journey from Earth to the Universe

The paragraph introduces the vast concept of comprehending the universe's size. It references Charles and Ray Eames’ 1977 film *Powers of Ten*, which visualized the universe's scale starting from a small scene near Lake Michigan and expanding out to the cosmos. The narrator plans a similar journey from Sicily, starting with a 1-meter scene and zooming out exponentially every 10 seconds, symbolizing the scale of the universe from human activity to the edge of the known universe.

05:01

🌍 Scaling Out: Earth and Human Impact

Beginning with human activity still visible from 1 kilometer away, this section zooms out to higher altitudes. At 10,000 meters, the influence of human presence becomes harder to detect. By 100,000 meters, viewers leave the atmosphere, and the entire planet becomes visible. The scene shifts to 10 million meters, where Earth appears as a small, blue dot, and the narrator begins to explore the solar system and beyond, describing the planets' orbits and the NASA Solar Dynamics Observatory monitoring the sun’s activity.

🛰️ Departing the Solar System

The journey reaches the outer edge of the solar system, passing by the orbits of the gas giants and dwarf planet Pluto. Voyager 1 and 2, launched in 1977, are mentioned as humanity’s furthest-reaching probes, heading into interstellar space. The sun becomes just one of billions of stars as the narrator highlights Alpha Centauri, the nearest star system, and reflects on the vast distances involved in interstellar travel. The paragraph ends with a mention of the Gaia spacecraft's efforts to map the stars in the Milky Way galaxy.

🌌 Milky Way and Beyond: Galactic Structures

Moving even farther, the journey enters the Milky Way, a spiral galaxy with over 100 billion stars rotating around a supermassive black hole, Sagittarius A*. The narrator explains how supermassive black holes are believed to exist at the center of most galaxies. The viewer is introduced to dwarf galaxies like the Magellanic Clouds, which are part of the local group of galaxies, before expanding outward to a million light years, where the Virgo Supercluster becomes visible.

🌀 Clusters of Galaxies and the Edge of Vision

The journey continues to clusters of galaxies, appearing as dots in a sea of space. The narrator describes how galaxies are arranged along filaments, such as the Pisces-Cetus Supercluster Complex. At 10 to the 26 meters, the journey switches to viewing the universe in microwave radiation, revealing the cosmic microwave background radiation, the remnant light from the Big Bang. The paragraph ends by pondering the limits of the universe and questioning what might lie beyond our current understanding.

✨ The Unknown Frontiers of the Universe

The final section reflects on the cosmic microwave background radiation, emitted 380,000 years after the Big Bang, and considers the possibility of even more universe beyond what is observable. The narrator speculates about ongoing expansion, other possible universes, and how our understanding may evolve by 2077. The journey concludes by paying homage to the Eames’ *Powers of Ten*, celebrating the vast and beautiful story of the universe, from the smallest scales to the cosmic extremes.

Keywords

💡Powers of Ten

Powers of Ten refers to the mathematical concept of scaling by factors of ten. In the video, it represents the journey from a picnic blanket to the farthest reaches of the universe, showing how perspectives change as distances increase exponentially. This concept is used to illustrate the vastness of the universe, much like the original film by Charles and Ray Eames.

💡Exponential Acceleration

Exponential acceleration describes how the perspective shifts rapidly as the distance increases by powers of ten. In the script, this concept is crucial as it helps the viewer understand how distances, which seem to grow linearly at first, actually expand exponentially as we move further from the picnic scene on Sicily to the edges of the universe.

💡Light Year

A light year is the distance that light travels in one year, approximately 9.46 trillion kilometers. In the video, light years are used to mark distances between stars and galaxies, beginning with Alpha Centauri and extending out to the Milky Way and beyond. It emphasizes the vastness of space that the video seeks to convey.

💡Milky Way

The Milky Way is the galaxy that contains our solar system. In the video, it is described as a spiral galaxy with billions of stars rotating around a supermassive black hole. This is a central element in the narrative as the video illustrates humanity’s place within one of many galaxies in the universe.

💡Sagittarius A*

Sagittarius A* is the supermassive black hole at the center of the Milky Way, with a mass 4.2 million times greater than the Sun. The video mentions this black hole to demonstrate that such entities exist at the heart of nearly all galaxies, illustrating a key aspect of cosmic structure.

💡Voyager Spacecraft

Voyager 1 and Voyager 2 are spacecraft launched in 1977 that have traveled beyond our solar system into interstellar space. The script highlights these probes to illustrate humanity’s first physical journey beyond the immediate confines of the solar system, linking the video to the concept of exploration and discovery.

💡Cosmic Microwave Background Radiation

Cosmic Microwave Background Radiation is the thermal radiation left over from the Big Bang. In the video, it marks the current limit of human vision into the universe. It’s used to illustrate the earliest observable moment in the universe, when matter began to form into galaxies after the Big Bang.

💡Supermassive Black Hole

A supermassive black hole is a black hole with a mass millions or billions of times that of the Sun. These objects are mentioned several times in the script, particularly in the context of galaxies like M87, to illustrate the incredible gravitational forces present in the universe that affect the formation and behavior of galaxies.

💡Alpha Centauri

Alpha Centauri is the closest star system to Earth, consisting of three stars. In the script, it represents humanity's closest stellar neighbor, and is used as an example to emphasize how far even the nearest stars are from us in terms of light years.

💡Big Bang

The Big Bang refers to the scientific theory that the universe began as a singularity about 13.8 billion years ago and has been expanding ever since. In the video, the concept of the Big Bang is connected to the cosmic microwave background radiation, explaining the origin of the universe and how it continues to evolve.

Highlights

Astrophysicists constantly grapple with the challenge of comprehending the size of the Universe.

The 1977 film 'Powers of Ten' by Charles and Ray Eames is one of the most creative pieces of science communication.

The film takes viewers on a journey from Earth to the edge of the known Universe and back again.

In homage to 'Powers of Ten', a similar journey through time and space is being taken, starting on the island of Sicily.

The journey begins with a 1-meter wide view, zooming out by powers of ten, showing how human activity fades into insignificance at larger scales.

By 100 meters wide, the movement becomes exponential, accelerating further from Earth.

At 10^5 meters, the distance the International Space Station travels in 10 seconds, human activity is no longer visible.

At 10^6 meters, the Earth's entire surface becomes visible, showing its delicate beauty from space.

Zooming out further, the orbits of planets and the structure of the solar system begin to appear.

Voyager 1 and Voyager 2, launched in 1977, have traveled beyond the solar system, marking humanity's first step into interstellar space.

Reaching a distance of one light year (10^16 meters), our closest star system, Alpha Centauri, comes into view.

The Milky Way is revealed as a vast spiral galaxy, containing hundreds of billions of stars and a supermassive black hole at its center.

Clusters of galaxies form along filaments in the vast voids of space, visible at 10^24 meters.

The cosmic microwave background radiation, visible at 10^26 meters, marks the furthest light emitted after the Big Bang.

Beyond the known Universe, theoretical debates arise about whether there is more universe yet to be revealed or if multiple universes exist with different properties.

Transcripts

Trying to comprehend how big the Universe is

is one of those questions that astrophysicists

grapple with all the time.

Trying to explain it in a way that's easy to understand,

well that's a whole other challenge.

In 1977, Charles and Ray Eames,

hugely influential American designers,

released one of the most elegant and creative pieces

of science communication of modern times -

Powers of Ten.

It took the viewers on a journey from a picnic blanket near Lake Michigan

to the edge of the known Universe, and back again.

Over 40 years later, as a humble homage

to this groundbreaking film,

we're going to take a similar journey through time and space

and see how our understanding has changed along the way.

As in 1977, we'll start with a picnic.

Though this time, we're on the island of Sicily in Italy,

rather than Lake Michigan.

We'll start with a scene one metre wide,

viewed from one metre away,

and every 10 seconds, we're going to move out to 10 times further away,

so the scene will be 10 times wider.

This square is 10 metres wide,

and in 10 seconds, the next square will be 10 times that.

The movement may seem linear,

but we're actually accelerating exponentially into the distance.

This square is 100 metres wide,

the distance someone can run in 10 seconds.

Well, if they're running at 43km/h, just under the speed of your cat.

One kilometre, though our picnickers are indistinguishable now,

we can still clearly see the impact of human activity on the world.

Ten thousand metres,

or 10 to the 4 metres,

this is the distance a supersonic plane travels in 10 seconds,

and we're now reaching the highest altitude flown by such a plane.

10 to the 5 metres,

this is the distance the International Space Station travels

in 10 seconds. There it goes.

From here on, human activity will be lost to sight,

we're at the scale of countries.

One million metres, or 10 to the 6 metres,

we've long left Earth's atmosphere,

and soon we'll see the whole planet. What a jewel.

Ten million metres.

The invisible magnetosphere

shields us from the dangerous ionising radiation of space.

10 to the 8 metres.

This line extends at the speed of light.

This is the time it takes for light to reach us from the moon's orbit,

the age of moonlight.

The Earth is now just a pale blue dot in a sky full of stars.

Even as we accelerate away,

the stars appear stationary because they're so much further away.

So much empty space.

Let's illustrate the orbits of the planets in our solar system,

otherwise this could get a bit dull.

Here comes the orbit of Venus,

then Mars,

and now Mercury.

Since 2010, the NASA Solar Dynamics Observatory

has been using an extreme ultraviolet filter

to monitor the activity of our Sun.

Finally, we reach the orbit of the outer planets,

the gas giants, but just specks at this distance.

There's the orbit of Pluto, one of the dwarf planets of the Kuiper belt.

10 to the 13 metres, and we're moving out of the solar system.

In 2012, the Voyager 1 spacecraft became the first human artefact

to make this journey,

followed in 2018 by its twin, Voyager 2.

Both were launched in 1977,

the year the Eames were working on Powers of Ten.

We're heading into interstellar space,

our Sun is just one of billions of stars,

and still at this distance, the night sky looks very similar

to what we see at home.

This square is 10 to the 16 metres,

the distance light travels in one year, one light year.

Here's our closest neighbour, Alpha Centauri.

Three stars for the price of one,

with planets orbiting around them.

I'd love to know what's going on there.

Thanks to data collected by the Gaia spacecraft,

we're building a detailed 3D map of the Milky Way.

There are between 100 and 400 billion stars in our galaxy alone,

and clouds of dust and gas, like these nebulae,

where new stars are born.

Images sent from the Hubble Space telescope

have been blowing our minds for a generation.

As we move away, we begin to the see the great flat spiral of our galaxy.

A few hundred billion stars rotating around a black hole,

Sagittarius A*, 4.2 million times more massive than our Sun.

we now think supermassive black holes

reside at the centre of nearly all galaxies.

These two dwarf galaxies are the Magellanic clouds

which, together with at least 80 others,

make up what's known as the local group of galaxies.

10 to the 22.

One million light years.

Soon we'll pass the supergiant elliptical galaxy M87.

And if we switch to radio waves,

we can glimpse the supermassive black hole at its centre.

Switching back to visible light, as we traverse the Virgo Supercluster,

each tiny dot not a star, but a galaxy.

Billions of stars floating in an ever-growing void.

10 to the 24 metres.

The limits of our vision in 1977.

But over 40 years later, we can show a bit more.

Clusters of galaxies arranged along filaments,

like the Pisces-Cetus Supercluster Complex.

At 10 to the 26 metres, we switch our view to microwave.

We can now see the current limit of our vision.

This light forms a wall all around us.

The light and dark patches show differences in temperature

by fractions of a degree,

revealing where matter was beginning to clump together

to form the first galaxies shortly after the Big Bang.

This light is known as the cosmic microwave background radiation.

10 to the 27 metres.

One followed by 27 zeros.

Beyond this point, the nature of the Universe is truly uncharted -

and debated.

This light was emitted around 380,000 years after the Big Bang.

Before this time, the Universe was so hot

that it was not transparent to light.

Is there simply more universe out there, yet to be revealed?

Or is this region still expanding -

generating more universe,

or even other universes

with different physical properties to our own?

How will our understanding of the Universe have changed by 2077?

How many more powers of ten are out there?

From a picnic blanket on Sicily to the very edge of our understanding,

I salute the Eames for the way they told this beautiful story.

The story of the Universe.