Cosmic Phenomena Explorer

Black Holes: Cosmic Vacuum Cleaners

Explore the mysterious regions of spacetime where gravity is so strong that nothing, not even light, can escape.

What is a Black Hole?

A black hole is a region of spacetime exhibiting gravitational acceleration so strong that nothing—no particles or even electromagnetic radiation such as light—can escape from it.

Most black holes form from the remnants of a large star that dies in a supernova explosion. If the total mass of the star is large enough (about three times the mass of the Sun), it can be proven theoretically that no force can keep the star from collapsing under the influence of gravity.

Stellar black holes: Formed by collapsing massive stars (3 to 10 solar masses)
Supermassive black holes: Millions to billions of solar masses, found at galaxy centers
Intermediate black holes: Hundreds to thousands of solar masses
Primordial black holes: Hypothetical, formed in the early universe

Event Horizon

The boundary around a black hole from which nothing can escape, not even light. It's the "point of no return."

Singularity

At the center of a black hole lies the singularity, where matter is crushed to infinite density and spacetime curvature becomes infinite.

Accretion Disk

A disk of superheated gas and dust spiraling into a black hole, often emitting powerful X-rays visible to telescopes.

Black Hole Simulation

Black Hole Mass (Solar Masses)

3 100

Spin Rate

Slow Fast

Accretion Disk Brightness

Dim Bright

Supernovae: Stellar Fireworks

Witness the spectacular explosion that marks the death of a star, outshining entire galaxies for weeks.

What is a Supernova?

A supernova is a powerful and luminous stellar explosion that occurs during the last evolutionary stages of a massive star or when a white dwarf is triggered into runaway nuclear fusion.

Type Ia: White dwarf in binary system accretes matter until it reaches critical mass (1.4 solar masses) and explodes
Type II: Massive star (8+ solar masses) collapses when it can no longer sustain nuclear fusion
Type Ib/Ic: Similar to Type II but the star has lost its outer hydrogen (Ib) or helium (Ic) envelope

Supernovae play a crucial role in distributing elements heavier than hydrogen and helium throughout the universe. They're also used as "standard candles" to measure cosmic distances. The iron in your blood, calcium in your bones, and gold in jewelry were all forged in supernova explosions.

Energy Release

A single supernova can briefly outshine an entire galaxy, releasing as much energy as the Sun will in its entire 10-billion-year lifetime.

Element Creation

Supernovae create and disperse heavy elements like iron, gold, and uranium into space, seeding future generations of stars and planets.

Neutron Stars

The core left behind after a Type II supernova may collapse into an incredibly dense neutron star, a teaspoon of which would weigh a billion tons.

Supernova Timeline

Core Collapse

Iron core collapses in milliseconds

Shock Wave

Rebound creates outward shock wave (1-2 hours)

Breakout

Shock reaches surface (hours to days)

Peak Brightness

Maximum luminosity (days to weeks)

Remnant

Expanding nebula (years to millennia)

Speed of Light: Cosmic Speed Limit

Discover why nothing in the universe can travel faster than light, and how this fundamental constant shapes our reality.

The Speed of Light

The speed of light in vacuum, commonly denoted as c, is a universal physical constant important in many areas of physics. Its exact value is 299,792,458 meters per second (about 186,282 miles per second).

According to Einstein's theory of relativity, the speed of light is constant in all inertial frames of reference, regardless of the motion of the source or observer. This constancy leads to phenomena like time dilation and length contraction.

Earth to Moon: ~1.28 seconds
Earth to Sun: ~8.3 minutes
Sun to Pluto: ~5.5 hours
Sun to nearest star (Proxima Centauri): ~4.24 years
Across Milky Way galaxy: ~100,000 years

Time Dilation

As objects approach light speed, time slows down for them relative to stationary observers. At light speed, time would stop completely.

Length Contraction

Objects moving near light speed appear shortened in the direction of motion to stationary observers.

Mass Increase

As velocity approaches light speed, relativistic mass increases toward infinity, requiring infinite energy to accelerate further.

Light Speed Calculator

Distance (light-years)

Speed (% of light speed)

Results:

Time on Earth: - years

Time for Traveler: - years

Due to relativistic effects, the traveler experiences less time than observers on Earth.

Cosmic Quiz

Test your knowledge about black holes, supernovae, and the speed of light!

Ready to test your cosmic knowledge?

This quiz contains 10 questions about black holes, supernovae, and the speed of light. You'll get immediate feedback after each question.