When a massive star explodes as a supernova, it releases a gigantic amount of energy — but here’s the mind-blowing fact:
🔹 99% of that energy is carried away by neutrinos!
🔹 And these neutrinos are incredibly tiny — about 20 femtometers in size.
They are the universe’s most mysterious and ghost-like particles… and they pass through your body trillions of times every second without you ever feeling it.
Let’s explore this cosmic mystery. 🌌
🔹 What Are Supernova Neutrinos?
A neutrino is an ultra-light, neutral particle with:
-
Almost no mass
-
No electric charge
-
No interaction with normal matter
-
Speed close to the speed of light!
They are so tiny (≈20 femtometers) that they make quarks look huge.
During a supernova, the star’s core collapses — producing a flood of neutrinos that escape instantly.
🔹 Why Do Supernovas Release Neutrinos?
Inside a collapsing star:
1️⃣ The core compresses to extreme density
2️⃣ Protons + electrons combine → neutrons + neutrinos
3️⃣ These neutrinos rush out with almost zero interaction
This burst is called a neutrino flash, and it carries away nearly all the exploding star’s energy.
🔹 How Small Is 20 Femtometers?
Let’s visualize:
-
Atom: 100,000 femtometers
-
Proton: 1 femtometer
-
Neutrino interaction range: ~20 femtometers
If an atom were the size of a football stadium…
a neutrino’s “interaction size” would be smaller than a single dust particle floating in the air.
That’s how ghost-like they are!
🔹 Why Are Supernova Neutrinos Important?
1️⃣ They explain how stars explode
Supernova neutrinos cool the star’s core and allow the explosion to happen.
2️⃣ They carry hidden information
Neutrinos escape immediately — before light — so they tell us:
-
When the star collapsed
-
How dense the core was
-
What elements were created inside
3️⃣ They help form new stars & planets
Neutrinos influence nuclear reactions that create heavier elements like:
-
Gold
-
Uranium
-
Platinum
Without supernova neutrinos, the universe would not have many of the elements we use today.
🔹 Where Are Supernova Neutrinos Detected?
Earth has giant underground detectors such as:
-
Super-Kamiokande (Japan)
-
IceCube Neutrino Observatory (Antarctica)
-
Sudbury Neutrino Observatory (Canada)
When a supernova happens, these detectors feel a sudden “pulse” of neutrinos…
often hours before the light reaches Earth.
🔹 Fun Fact
In the famous 1987 supernova (SN 1987A), scientists detected 25 neutrinos —
which confirmed how supernova explosions really work.
Those 25 neutrinos changed astrophysics forever.
📘 Frequently Asked Questions (Frequently Asked Questions)
1️⃣ What is the size of a supernova neutrino?
Its effective interaction size is around 20 femtometers, extremely tiny.
2️⃣ How much energy do neutrinos carry in a supernova?
About 99% of the entire explosion’s energy.
3️⃣ Can neutrinos pass through Earth?
Yes — almost all of them pass straight through Earth without any interaction.
4️⃣ Do neutrinos have mass?
Yes, but extremely small — the lightest mass of any known particle.
5️⃣ Why are neutrinos so hard to detect?
Because they do not interact with electric charge or strong nuclear forces.
6️⃣ How fast do neutrinos travel?
Almost at the speed of light.
