GCSE Science · Space Research Guide

The universe has
open questions.

Pick something you're curious about. Each card gives you a real question to investigate and the best places on the internet to find answers — from NASA to the BBC.

Start with a question

Don't search for a topic — search for a question. "Why do stars explode?" gets better results than "supernovae."

🔬

Check who wrote it

NASA, ESA, and university sites are reliable. Random blogs may not be. Look for authors with real credentials.

🔄

Find where scientists disagree

The best research topics have unresolved questions. If everyone agrees, there's not much to explore.

📊

Look for real data

The best projects include actual numbers, graphs, or observations — not just descriptions of what happens.

Solar System

Why was Pluto demoted to a dwarf planet?

In 2006 the IAU changed the rules for what counts as a planet. Pluto failed one of the three criteria. But not all scientists agreed — the debate is still live.

Solar System

Is there water on Mars — and why does it matter?

We've found ice, ancient riverbeds, and possible underground lakes. But liquid water is a very different question. The evidence is genuinely contested.

Solar System

What would happen to Earth without the Moon?

The Moon stabilises our axial tilt, drives the tides, and slows Earth's spin. Without it, Earth's axis could wobble chaotically — and life would look very different.

Stars & Lifecycles

How do we know how old the Sun is?

Surprisingly, the most reliable method isn't looking at the Sun itself — it's radioactive dating of the oldest meteorites. The Sun and the solar system formed from the same cloud of gas.

Stars & Lifecycles

Why do some stars explode and others just fade away?

Mass is the deciding factor. Stars like our Sun end as white dwarfs. Massive stars die in spectacular supernova explosions that forge the heavy elements in your body.

Stars & Lifecycles

Neutron stars: city-sized objects more massive than the Sun

When a massive star explodes, the core can collapse to a sphere just 20 km across but containing more mass than the Sun. A teaspoon would weigh a billion tonnes.

Big Bang & Cosmology

What is the cosmic microwave background, and why does it matter?

The CMB is the afterglow of the Big Bang, light left over from 380,000 years after the universe began. It was discovered accidentally by two engineers trying to fix a noisy antenna.

Big Bang & Cosmology

Why is the night sky dark? (Olbers' Paradox)

If the universe is infinite and full of stars, every line of sight should end at one — making the whole sky as bright as the Sun. The fact it isn't tells us something profound about the universe's age and expansion.

Big Bang & Cosmology

How do we know the universe is expanding?

Edwin Hubble noticed in 1929 that distant galaxies are moving away from us — and the further away, the faster they recede. His original data is simple enough to analyse yourself.

End of the Universe

The Big Freeze: how the universe slowly dies

If dark energy keeps accelerating expansion, stars will burn out, black holes will slowly evaporate, and the universe will reach heat death — maximum entropy where nothing can happen. On a timescale of 10¹⁰⁰ years.

End of the Universe

The Big Rip: if dark energy grows stronger

If dark energy increases over time, expansion could eventually overpower gravity, electromagnetism, and even the nuclear force — tearing apart atoms themselves in a finite time.

End of the Universe

The Big Crunch: could the universe collapse?

If there's enough mass, gravity could eventually reverse the expansion and everything could collapse back toward a final singularity — the mirror image of the Big Bang. Current evidence says this is unlikely, but not ruled out.

End of the Universe

Do protons decay? (And why does it matter?)

Most end-of-universe scenarios require protons to eventually decay. We've never observed it happening, but experiments deep underground are watching billions of them constantly, waiting for one to vanish.

Space Exploration

James Webb vs Hubble: what's actually different?

JWST sees in infrared, allowing it to peer through dust clouds and see the very first galaxies. The side-by-side comparison images are striking — and they tell you a lot about how telescopes work.

Space Exploration

The Voyager probes: still talking after 47 years

Launched in 1977, Voyager 1 is now over 24 billion km away — and still sending data. The signal takes more than 22 hours to reach us. They've crossed into interstellar space and are humanity's most distant objects.

Space Exploration

Why is returning to the Moon so hard?

We went in 1969 with 1960s technology. So why is it taking until the 2020s to go back? The answer involves budget, politics, radiation, and exactly what we're trying to achieve this time.

Big Mysteries

What is dark matter — and do we actually know it exists?

About 27% of the universe is made of something we can't see, touch, or directly detect — we only know it's there from its gravitational effects. Galaxies would fly apart without it. But we have no idea what it is.

Big Mysteries

The Fermi Paradox: where is everyone?

The universe is 13.8 billion years old and contains trillions of stars with planets. Intelligent life should have had time to spread everywhere — so why haven't we heard from anyone?

Big Mysteries

Gravitational waves: listening to ripples in spacetime

Einstein predicted gravitational waves in 1916. We only detected them in 2015 — from two black holes that merged over a billion light-years away. The signal lasted 0.2 seconds and stretched space by less than a proton's width.