Astronomy · Core Systems

Stellar Scale

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To visualize a system that captures the mind-bending scale of the universe, we have to look at objects that differ in size by factors of millions.

This "neighborhood" aligns the smallest, densest corpses of dead stars alongside the absolute titans of the cosmos, ending with an ultra-massive black hole so large it defies human intuition.


How to View:

Scroll down and keep zooming out. You will continually have to widen your scale to comprehend the next object in the sequence!

Celestial Bodies (21)

Neutron Star
star · system center · 20 km diameter
Compact Remnant Degenerate Matter

The ultimate "small but mighty" object. About the size of a city (20 km in diameter), but weighing 1.5 times the mass of the Sun.

Stellar-Mass Black Hole
star · system center · 1,800,000 km · 180 km diameter
Singularity Stellar Mass

The result of a supernova. Paradoxically, the physical "size" of the Event Horizon is tiny—only about 30 to 60 km across.

White Dwarf (e.g. Sirius B)
star · system center · 5,500,000 km · 12,742 km diameter
Class D Earth-Sized

Roughly the size of Earth, representing the glowing, intensely hot core of a dead Sun-like star.

Brown Dwarf (Teide 1)
star, protostar · system center · 8,500,000 km · 140,000 km diameter
Sub-Stellar Object Brown Dwarf

Often called a "failed star." It is roughly the same physical size as Jupiter, but packs up to 80 times the mass, generating a faint, smoldering heat without true fusion.

Red Dwarf (Proxima Centauri)
star · system center · 15,000,000 km · 214,000 km diameter
Class M Main Sequence

The most common stars in the universe. Small, cool, and dim—roughly 15% the size of the Sun.

Yellow Dwarf (The Sun)
star · system center · 25,000,000 km · 1,391,000 km diameter
Class G Main Sequence

Our baseline for measurement. It is nearly 1.4 million km across.

Blue Main Sequence (Vega)
star · system center · 50,000,000 km · 3,500,000 km diameter
Class A Main Sequence

Hotter, larger, and significantly brighter than our Sun, measuring about 2.5 times its radius.

Wolf-Rayet (WR 104)
star · system center · 120,000,000 km · 14,000,000 km diameter
Class W Evolved

A hyper-violent, dying star shedding its outer layers at millions of kilometers per hour in a blinding ultraviolet fury.

Supermassive Black Hole (Sag A*)
star · system center · 220,000,000 km · 60,000,000 km diameter
Singularity Supermassive

Found at galactic centers. The one at the heart of our Milky Way has an event horizon about 17 times the size of the Sun.

Red Giant (Aldebaran)
star · system center · 340,000,000 km · 63,000,000 km diameter
Class K Giant Evolved

An evolved star that has exhausted its core hydrogen and expanded to roughly 45 times the solar radius.

Blue Supergiant (Rigel)
star · system center · 550,000,000 km · 112,000,000 km diameter
Class B Supergiant

Massive, highly luminous, and roughly 80 times the size of the Sun.

Luminous Blue Variable (Pistol Star)
star · system center · 900,000,000 km · 400,000,000 km diameter
Class O Hypergiant Highly Unstable

One of the most luminous and massive stars known. It radiates as much energy in 20 seconds as our Sun does in a year, and is constantly on the verge of blowing itself apart.

Carbon Star (La Superba)
star · system center · 2,200,000,000 km · 500,000,000 km diameter
Class C Giant Carbon-Rich

A smoldering, highly evolved giant star choked by soot and ruby-red carbon compounds in its upper atmosphere.

Yellow Hypergiant (Rho Cassiopeiae)
star · system center · 3,800,000,000 km · 630,000,000 km diameter
Class G Hypergiant Unstable

An extremely rare, highly unstable yellow star going through violent eruptions, measuring roughly 450 times the radius of the Sun.

Red Supergiant (Betelgeuse)
star · system center · 6,000,000,000 km · 1,600,000,000 km diameter
Class M Supergiant

One of the largest stars visible to the eye. If placed at the center of our system, it would swallow the inner planets and extend past the orbit of Jupiter.

Hypergiant (UY Scuti)
star · system center · 9,000,000,000 km · 2,900,000,000 km diameter
Class M Hypergiant

Unstable and nearing the end of their lives, these represent the absolute limit of stellar volume. Roughly 1,700 to 2,100 times the radius of the Sun.

Ultra-Massive Black Hole (TON 618)
star · orbits Neutron Star · 520,000,000,000 km · 388,900,000,000 km diameter
Singularity Ultra-Massive

The true titan. TON 618 has a Schwarzschild radius of about 1,300 AU. It is so large that our entire solar system would look like a speck of dust inside it.

TON 618 Accretion Disk
region · orbits Ultra-Massive Black Hole (TON 618) · -500,000,000,000 km–500,000,000,000 km
Superheated Plasma Quasar

A swirling maelstrom of superheated plasma trapped in the black hole’s gravitational grip. Here, matter is accelerated to such extreme velocities that it ignites, transforming the void into a quasar glowing with the luminosity of 140 trillion suns.

TON 618 Photon Sphere
region · orbits Ultra-Massive Black Hole (TON 618) · -292,000,000,000 km–292,000,000,000 km
Trapped Light Relativistic

The boundary where gravity is so strong that light itself is forced to travel in orbits. If you stood here and looked straight ahead, you would see the back of your own head.

TON 618 Event Horizon
region · orbits Ultra-Massive Black Hole (TON 618) · -194,450,000,000 km–194,450,000,000 km
Gravitational Boundary

The absolute point of no return. Spanning approximately 390 billion kilometers in diameter, this gravitational boundary is so vast that the orbit of Neptune would fit across it over 40 times. It is a region where spacetime is so warped that not even light—the fastest thing in the universe—possesses enough energy to escape.

Sun's Hill Sphere
region · orbits Yellow Dwarf (The Sun) · 18,921,440,000,000 km–18,921,460,000,000 km
Boundary Interstellar

To put gravity into perspective: The Sun's gravitational dominance extends ~2 light-years into space. This invisible sphere of influence is nearly 100 times wider than the physical size of TON 618!