SEA: Space Exploration & Astronomy

The Solar System is home to eight principal planets, but this is far from the full picture. Hidden beyond the orbit of Neptune are dozens of small, icy worlds, known as Dwarf Planets, or Minor Planets! The best example is Pluto, but there are dozens more orbiting within the same band of material in the outer Solar System. Today, we will visit these frozen, far out worlds first hand. MUSIC: - Mist...

What lies at the edge of the Solar System? Far beyond the orbit of Neptune and the Kuiper Belt, deep into interstellar space, we find a vast, thick shell of icy space debris. We have never seen it directly, but we know it exists- because it is the source of the most distant comets that we see entering the Solar System. So why is it there? Today we'll find out. All background songs in this vide...

Most large planets have moons. We have discovered almost 200 in our Solar System alone, and so we expect that the Milky Way is teeming with many more- perhaps even outnumbering planets and stars. With so many moons, it adds a plethora of additional holdouts in the galaxy capable of supporting life, and thus they are tantalising targets for scientists. However, extra-Solar moons are so insanely dis...

Europa is a fascinating moon, which is thought to be hiding a global ocean below its frozen surface. This makes it a hotspot for research and missions, with the ultimate goal being to identify an independent life source. In this video, we will go over this iconic satellite of Jupiter by the numbers, as we blow its perplexing mysteries wide open. All background music came from the Royalty-Free &amp...

Not every star in the universe can be seen shining brightly in the night sky. There are dozens of types of fascinating hypothetical stars, which are characterised by their extreme behaviour. Today, we will be taking a look at a few of these corrupted stars, from the start of the universe right up until the end. MUSIC TRACKS: - Passing a Foreign Moon - I Think I Can Help You (YouTube Audio Library)...

Not every galaxy is a fully formed spiral or elliptical galaxy. Some are much smaller, and orbit larger galaxies as well as each other, like ghosts. Today, we will examine these ghost galaxies- the satellites of the Milky Way and Andromeda. SOUNDTRACK: - The Sun is Scheduled to Come Out Tomorrow - Chris Zabriskie - Cylinder Four - Chris Zabriskie - I Can't Imagine Where I'd Be Without It -...

Supervoids are the enormous, empty spaces between galaxy clusters and galaxy filaments. But just because they are empty, doesn't mean they can't be filled with fascinating science! They have taught us a great deal about both galaxy structures in the early universe, and how they grow in the present. And today we'll be venturing into a few of the biggest! MUSIC: - Long Walks [Emily A Spr...

Quasars are the brightest phenomenon in the entire universe, able to outshine any type of star, and even entire galaxies containing hundreds of billions of them. They are the product of monster black holes at the centres of large galaxies, and so when we find multi-billion light year clusters of quasars dotted around the early universe, we are forced to reconsider some of our most fundamental assu...

Stars come in a wide range of sizes, but how do we calculate a star's size to determine which is the largest? In this episode, we will find out how stars are measured to determine their mind-boggling sizes, and above all, which of them are the biggest of all. PLEASE NOTE: This one is an older video of mine, back in 2021 when it was thought that the largest known star was Stephenson 2-18. It ha...

No matter where you are, you are always moving. The Earth orbits the sun, while the sun moves round the galaxy. But what makes the galaxy move? That is the topic of our video today. Everything in our local galaxy supercluster, Laniakea, is being dragged towards a high concentration of mass obscured by the opaque clouds of our galaxy, but what is it? It has all the ingredients for an epic cosmic my...

How large is the universe? Where does it begin and end? How does it expand? These are some of the biggest questions of astronomy- and while humanity is so small that we may never be able to fully understand the universe's true scale, advancements in technology are helping us to look ever-deeper into space, towards the edge of our observable universe known as the Cosmic Horizon. Today, we will get...

What we perceive to be the edge of our universe is not the actual edge of the universe, with most scientists in agreement that more space lies hidden beyond what we're able to see. Last time out, we travelled to the very edge of our observable universe. But today, we will be going even farther, as we wade out into the darkness of the unobservable universe. Soundtrack by CO.AG Music: https://www.yo...

Ever wonder what it would be like to fly all the way to the edge of space? Well in this video, we'll be doing just that. Using beautiful images snapped by the Hubble and James Webb telescopes, we will embark on a tour of our universe- venturing deep into the darkness, and uncovering the most jaw-dropping landmarks along the way. This is our journey to the edge of the universe. SOUNDTRACK [In o...

In 1998, two teams of scientists measured the universe's rate of expansion, expecting to find it slowing down on route to a collapse. But instead, they found the opposite- the universe's expansion appears to be accelerating, having expanded more in the latter half of its life. In attempting to explain this mysterious behaviour, they revived one Einstein's long-since-forgotten ideas. Th...

Dark Matter is a theoretical form of invisible mass, which has never been definitively detected. You've probably heard of it before, as it makes up a large part of the physics you find in textbooks. But how can something that's never been seen have so much scientific confidence behind it? Furthermore, if we can't see it, how do we know that it is really there? And if it's not, what are the alterna...

Lately, there has been talk of a new largest black hole, named Phoenix A*, which is said to have a mass greater than 100 billion times the mass of the sun! This is much larger than the previous record holder, TON-618. But can we really rely on this prediction? And if not, then what is the largest black hole out there, and how do we know its true size? These are the questions we will answer in sear...

The Cosmic Microwave Background (CMB) is the oldest light in the universe that we can see or detect. It was emitted only 380,000 years after the universe was born, back when it was a much more chaotic place. This microwave-band static is fundamentally linked to the Big Bang, and if we map it precisely enough, we can discover a wealth of information about the age, composition and structure of the u...

Saturn's most distinguished feature are its brilliant, shining rings, which have intrigued astronomers since the 17th century. But in the 1980s, Voyagers 1 & 2 revealed to us that each of the large planets in the Solar System is home to a ring system, but each varies wildly in its composition, arrangement, and substantiality. In this video, we will explore the complex and elegant natural p...

What is the largest galaxy? For a long time, the largest was thought to be IC 110. But since 2022, there has been talk of a new, even larger galaxy, Alcyoneus, which is said to be more than 16 million light years in diameter! But is that what's really being proposed in the original paper detailing the discovery? Not exactly, because Alcyoneus is a Radio Galaxy. But what is a radio galaxy, and...

Supernovae are some of the brightest and most powerful explosions in the universe, bright enough to outshine entire galaxies. These cosmic catastrophes come in many varieties, characterised by their elements and light. Today, we will cover the various types of supernova as we take a deep dive into these tremendous explosions. SOUNDTRACK: - Woodstock | Joni Mitchell: https://youtu.be/cRjQCvfcXn0 -...

One of astronomy's great, enduring mysteries is what really happens on the inside of a black hole. We know that anything which gets too close to a black hole is destroyed, but if you were able to jump right inside of one, then what would happen and where would you go? Today, we will explore a few of the many exotic and fascinating possibilities for what lies on the other side of a black hole....

The Milky Way is surrounded by more than 50 near neighbour galaxies that make up the Local Group. The two largest galaxies are us and Andromeda, but we also have an often-overlooked third large galaxy in our neighbourhood- the Triangulum Galaxy. This galaxy is like its own mini-Milky Way, containing stars, clouds, clusters, supernova remnants, and satellites. These are the checkpoints in the Trian...

The Andromeda Galaxy is our massive galactic neighbour, a spiral galaxy more than double the size of the Milky Way. In this video, we will be taking a journey, from this galaxy's ancient history, right up to its remote future- using the latest and most beautiful images to know our cosmic neighbour like never before. This is our journey to the Andromeda Galaxy... Soundtrack by CO.AG Music: http...

On the darkest of nights, free from the glow of the moon and the haze of light pollution, a stunning, striking formation can be seen imprinted upon the sky. That imprint is our galaxy- the Milky Way. Our galaxy is a giant, which extends for hundreds of thousands of light years. But by measuring the motions and velocities of the stars in our neighbourhood, both their past and future trajectories ca...

How old is the oldest planet? When did the first planets form in the universe? And what about life-supporting worlds? These are some of the most complex questions in extrasolar-planetary science. But by studying the ancient exoplanets in the Milky Way galaxy, we've managed to build up a comprehensive picture of when the genesis planets formed, and what they were like. Those findings make up th...