✦ Official NASA Media ✦

NASA Space Observatory

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NASA Hubble Space Telescope Gallery

Official NASA Hubble • Flickr

Browse thousands of breathtaking real images captured by the Hubble Space Telescope — from swirling galaxies and colorful nebulae to distant star clusters. All images are free and official from NASA.

🔭 Open NASA Hubble Gallery →

NASA James Webb Space Telescope Gallery

Official NASA Webb • Flickr

The James Webb Space Telescope captures the universe in infrared light — revealing galaxies that formed just 300 million years after the Big Bang, hidden star nurseries, and the atmospheres of distant exoplanets.

🌌 Open NASA Webb Gallery →

NASA Eyes on the Solar System

Interactive 3D Explorer • nasa.gov

Explore every planet, moon, asteroid and spacecraft in our solar system — shown at their real positions right now. A fully interactive 3D space experience directly from NASA.

🪐 Open NASA Eyes →

✦ Essential Knowledge ✦

Space Information

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Observable Universe

93 billion light-years in diameter, containing ~2 trillion galaxies, each home to hundreds of billions of stars.

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Temperature of Space

Deep space sits at −270.45°C (2.7 K) — the Cosmic Microwave Background remnant of the Big Bang.

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Speed of Light

299,792 km/s. It takes 8 minutes to reach Earth from the Sun, 4 years to Proxima Centauri, 2.5M years to Andromeda.

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Dark Matter & Energy

27% dark matter + 68% dark energy = 95% of everything. Ordinary matter — all we can see — is just 5%.

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The Big Bang

13.8 billion years ago, our universe expanded from an infinitely hot, dense singularity. Atoms formed within 380,000 years.

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Space is Silent

No air molecules means no sound. Spacecraft use radio waves to communicate — electromagnetic signals that travel at light speed.

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Gamma Ray Bursts

The brightest explosions in the universe — releasing more energy in seconds than the Sun will in its entire 10-billion-year lifetime.

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Gravitational Waves

Ripples in spacetime caused by colliding black holes or neutron stars. First detected by LIGO in 2015, predicted by Einstein in 1916.

✦ 2 Trillion Islands of Stars ✦

Galaxies

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The Milky Way

Our Home Galaxy

The Milky Way is a barred spiral galaxy ~100,000 light-years across, containing 200–400 billion stars. Our solar system sits in the Orion Arm, 26,000 light-years from the galactic core. At the center: Sagittarius A*, a supermassive black hole 4 million times the mass of the Sun.

100,000 ly wide400B starsSag A* at centerBarred spiral

Spiral Galaxies

The Most Recognisable Type

Spiral galaxies feature sweeping arms of stars, gas, and dust. Andromeda (M31), 2.5 million light-years away, is our nearest large neighbour — and is on a collision course with the Milky Way, set to merge in ~4.5 billion years.

Andromeda — 2.5M lyCollision ~4.5B yr~60% of galaxies

Elliptical & Irregular Galaxies

Other Forms

Elliptical galaxies are featureless ellipsoids containing mostly old, red stars. Irregular galaxies have no clear shape — often the result of galactic collisions. The Large Magellanic Cloud, visible from the Southern Hemisphere, is an irregular satellite of the Milky Way.

Oldest starsLittle star formationLMC — irregular

✦ 8 Worlds, Infinite Wonder ✦

Planets

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Rocky Planets

Mercury, Venus, Earth, Mars

Earth is the only known world with liquid water and complex life. Mars hosts Olympus Mons — the solar system's tallest volcano at 22 km. Venus has a runaway greenhouse atmosphere at 465°C — hotter than Mercury despite being farther from the Sun.

4 rocky worldsLife on EarthMars — 22 km volcano

Gas Giants — Jupiter & Saturn

The Outer Giants

Jupiter could contain 1,300 Earths. Its Great Red Spot is a storm over 350 years old. Saturn's rings span 282,000 km yet are only 10–100 m thick. Europa and Enceladus may harbour subsurface oceans with conditions for life.

Jupiter — 1300 EarthsSaturn's ringsEuropa — subsurface ocean

Ice Giants — Uranus & Neptune

The Distant Twins

Uranus spins on its side (98° axial tilt) — likely knocked over by an ancient giant impact. Neptune has the strongest winds in the solar system, reaching 2,100 km/h, despite receiving 900× less sunlight than Earth.

Uranus — 98° tiltNeptune — 2100 km/h windsIce giants

✦ 13.8 Billion Years of History ✦

The Universe

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The Big Bang & Cosmic Inflation

Origin Story

13.8 billion years ago, the universe expanded from an infinitely hot singularity. In the first second, cosmic inflation expanded space faster than light. Within 380,000 years, atoms appeared and light traveled freely — the CMB (Cosmic Microwave Background) is that first light, still detectable today.

13.8B years agoCMB still detectableInflation theory

The Cosmic Web

Large-Scale Structure

On the largest scales, matter forms a cosmic web of filaments, sheets, and voids. The Hubble Ultra Deep Field image — a tiny patch of sky — revealed over 10,000 galaxies. The observable universe contains around 2 trillion galaxies.

2 trillion galaxiesCosmic voidsDark matter skeleton

Fate of the Universe

Possible Endings

Possible fates include the Big Freeze (max entropy), Big Rip (dark energy tears everything apart), or Big Crunch (collapse). Current evidence favours the Big Freeze — in ~100 trillion years, star formation ceases and the cosmos descends into cold darkness.

Accelerating expansionBig Freeze (likely)100T years to dark

✦ Infinite Parallel Realities ✦

The Multiverse

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Eternal Inflation & Bubble Universes

Level I & II Multiverse

In eternal inflation, quantum fluctuations cause regions to stop inflating, each becoming a "bubble universe." Our entire observable universe may be one bubble in an infinite foam — each with potentially different physical constants, dimensions, and laws.

Eternal inflationBubble universesDifferent physics

Many-Worlds Interpretation

Quantum Branching

Hugh Everett's 1957 interpretation proposes every quantum event causes the universe to branch — one for each possible outcome. Every quantum measurement that could go multiple ways does go multiple ways, in separate, non-communicating branches of reality.

Hugh Everett — 1957Quantum branchingNo wave collapse

String Theory Landscape

10⁵⁰⁰ Possible Universes

String theory predicts up to 10⁵⁰⁰ different possible universes — the "landscape" — each with its own physical constants. In most, atoms cannot form or stars cannot ignite. We exist in one of the rare configurations compatible with life.

10⁵⁰⁰ vacuaExtra dimensionsAnthropic principle

✦ Where Physics Breaks Down ✦

Black Holes

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Formation & Types

How Black Holes Are Born

Black holes form when massive stars exhaust their fuel and collapse. M87* — the first-ever photographed black hole, imaged in 2019 by the Event Horizon Telescope — is 6.5 billion solar masses. Sagittarius A*, at our galaxy's center, is 4 million solar masses.

Stellar & SupermassiveM87* — 20196.5B solar masses

Event Horizon & Singularity

The Point of No Return

Beyond the event horizon, not even light escapes. Time dilation becomes extreme — a clock near it appears to slow to a stop for a distant observer. At the center is the singularity — infinite density where all known physics breaks down.

Event horizonTime dilationSingularity

Hawking Radiation

Quantum Effects & the Information Paradox

Stephen Hawking predicted that quantum effects cause black holes to slowly emit thermal radiation and evaporate over astronomical timescales. The Information Paradox — what happens to information about matter that fell in? — remains one of the deepest unsolved problems in physics.

Hawking radiationEvaporationInformation paradox

✦ Our Star ✦

The Sun

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Structure & Nuclear Fusion

G-Type Main Sequence Star

The Sun is 1.39 million km across (109 Earths), containing 99.86% of the solar system's mass. At its 15-million°C core, nuclear fusion fuses 620 million tonnes of hydrogen into helium per second. That energy takes 100,000 years to reach the surface but only 8 minutes to reach Earth.

4.6B years old5,778 K surface109× Earth's size

Solar Activity

Flares, Sunspots & Solar Wind

The Sun follows an 11-year activity cycle. Solar flares and coronal mass ejections (CMEs) can disrupt satellites, GPS, and power grids. The solar wind streams charged particles creating Earth's auroras and shaping the heliosphere — a bubble extending 125 AU.

11-year cycleSolar windAurora creation

Life Cycle & Death

Red Giant → White Dwarf

In ~5 billion years, the Sun expands into a red giant, engulfing Mercury and Venus. It then sheds its outer layers as a planetary nebula, leaving a white dwarf — roughly Earth-sized — slowly cooling over trillions of years.

5B years leftRed giant phaseWhite dwarf end

✦ Where Stars Are Born & Die ✦

Nebulae

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Emission Nebulae — Stellar Nurseries

Birthplaces of Stars

Emission nebulae are ionised gas clouds glowing from radiation of nearby hot stars. The Orion Nebula (1,344 ly away) is the nearest star-forming region, visible to the naked eye. The Pillars of Creation — towering star-forming columns 7,000 ly distant — were famously imaged by Hubble in 1995 and re-imaged by JWST in 2022.

Orion — 1,344 lyPillars — 7,000 lyJWST 2022

Planetary Nebulae

Death Shrouds of Sun-like Stars

When a Sun-like star dies, it sheds its outer layers as a glowing planetary nebula. The Helix Nebula (650 ly away) is nicknamed the "Eye of God." The Ring Nebula (M57) is the remnant of a star that died ~6,500 years ago, with a white dwarf at its center.

Helix — "Eye of God"Ring Nebula — M57White dwarf core

Supernova Remnants

Aftermath of Stellar Explosions

When a massive star explodes as a supernova, ejected material expands as a supernova remnant. The Crab Nebula (SN 1054, observed by Chinese astronomers) contains a pulsar spinning 30 times/second at its heart. These remnants seed the galaxy with heavy elements — including the iron in your blood.

Crab — SN 1054Pulsar at centerSeeds heavy elements

✦ Nuclear Furnaces ✦

Stars

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Star Classification

Spectral Types O B A F G K M

Stars are classified by temperature. Blue O-type supergiants are hottest and most massive but short-lived. Red M-type dwarfs are cool, dim, and live for trillions of years — they're 70% of all stars. Our G-type Sun is middle-of-the-road, ideal for stable long-term planetary conditions.

O B A F G K MSun = G-typeRed dwarfs — 70% of stars

Neutron Stars & Pulsars

Stellar Remnants

Neutron stars are just 20 km across but denser than atomic nuclei — a teaspoon weighs a billion tonnes. Pulsars are rotating neutron stars emitting beams of radiation with clock-like precision, used as natural cosmic timekeepers to test general relativity.

20 km acrossBillion tonnes/teaspoonPulsars — cosmic clocks

✦ Remnants of Creation ✦

Asteroids & Comets

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The Asteroid Belt

Between Mars & Jupiter

Between Mars and Jupiter lie millions of rocky bodies from dust grains to Ceres (940 km, a dwarf planet). Despite movie depictions, the belt is mostly empty — a spacecraft flying through is unlikely to encounter a single asteroid. These are the building blocks of a planet that never formed due to Jupiter's gravity.

Ceres — dwarf planetJupiter prevented formationRocky & metallic

Comets — Dirty Snowballs

Ice, Dust & Spectacular Tails

Comets are icy bodies from the Kuiper Belt or Oort Cloud. Near the Sun, solar heat vaporises ice, creating a glowing coma and twin tails — dust and ion. Halley's Comet returns every 75–76 years. The Rosetta mission in 2014 achieved the first-ever comet landing, on Comet 67P.

Halley's — 75 yr periodOort Cloud originRosetta — first landing

✦ 95% of Everything is Hidden ✦

Dark Matter & Dark Energy

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Dark Matter

The Invisible Skeleton of the Universe

Dark matter makes up ~27% of the universe but doesn't emit, absorb, or reflect light. Its existence is inferred from galaxies rotating too fast for their visible mass, and from gravitational lensing bending light more than visible matter can account for. Leading candidates: WIMPs and axions — neither yet directly detected.

27% of universeWIMPs & axionsGravitational evidence

Dark Energy

The Force Accelerating Cosmic Expansion

Dark energy (~68% of the universe) was discovered in 1998 from observations of distant supernovae. It acts as a negative pressure, pushing galaxies apart at an accelerating rate. The simplest explanation is Einstein's cosmological constant — an intrinsic energy of empty space. Its nature remains cosmology's biggest open question.

68% of universeDiscovered 1998Cosmological constant

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Why Space?

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Inspiration

Scale of the Universe

ISS Live Tracker

NASA Space Observatory

NASA Hubble Space Telescope Gallery

NASA James Webb Space Telescope Gallery

NASA Eyes on the Solar System

Space Information

Observable Universe

Temperature of Space

Speed of Light

Dark Matter & Energy

The Big Bang

Space is Silent

Gamma Ray Bursts

Gravitational Waves

Galaxies

The Milky Way

Spiral Galaxies

Elliptical & Irregular Galaxies

Planets

Rocky Planets

Gas Giants — Jupiter & Saturn

Ice Giants — Uranus & Neptune

The Universe

The Big Bang & Cosmic Inflation

The Cosmic Web

Fate of the Universe

The Multiverse

Eternal Inflation & Bubble Universes

Many-Worlds Interpretation

String Theory Landscape

Black Holes

Formation & Types

Event Horizon & Singularity

Hawking Radiation

The Sun

Structure & Nuclear Fusion

Solar Activity

Life Cycle & Death

Nebulae

Emission Nebulae — Stellar Nurseries

Planetary Nebulae

Supernova Remnants

Stars

Star Classification

Neutron Stars & Pulsars

Asteroids & Comets

The Asteroid Belt

Comets — Dirty Snowballs

Dark Matter & Dark Energy

Dark Matter

Dark Energy

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