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Astrophysics

What Is Astrophysics?

Astrophysics uses physics to explain how things in space actually work. Not just what they are, but why they behave the way they do. How does a star produce energy for billions of years? What happens to space and time near a black hole's event horizon? Why is the universe expanding faster than models based on known physics predict?

The questions are hard. The math behind them is harder. But the findings have a way of being genuinely strange in ways that are worth understanding even without a physics background.

What This Category Covers

• Stellar physics: the internal structure of stars, nuclear fusion, how the balance between gravity and radiation pressure shifts over time, and what determines whether a star ends as a white dwarf, neutron star, or black hole
• Black holes: event horizons, Hawking radiation, the information paradox, what gravitational wave detections reveal about mergers, and ongoing interpretation of Event Horizon Telescope results
• Gravitational waves: how LIGO and Virgo work, what detections have confirmed, and what they've turned up that theorists didn't expect. A genuinely new way of reading the universe that doesn't rely on light at all
• Dark matter and dark energy: together they make up most of the universe by current estimates, and we don't know what either of them is. Coverage here tracks both the evidence and the active debates about what they might be
• Cosmology: the structure and history of the universe from the first moments after the Big Bang through to current models of its future
• High energy phenomena: pulsars, magnetars, gamma ray bursts, and the physics of matter under extreme conditions

Dark matter and dark energy deserve a particular note. The fact that we don't know what they are is not a fringe position. It's the mainstream scientific situation, and honest coverage of astrophysics has to sit with that uncertainty rather than paper over it.

We write about astrophysics for readers who are curious and willing to go deeper, but don't have a graduate level background in physics. The goal is accurate, not oversimplified.