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1.3 billion years ago two black holes merged; the author says that in the final…

2026-05-13 · 05:34 UTC ·@aakashgupta ·1 min read

Brief

Aakash Gupta presents the LIGO GW150914 detection as a reset of what "powerful" and "precise" mean: two black holes merged 1.3 billion years ago, converting ~3 solar masses to energy and peaking at ~3.6×10^49 W; the wave arrived Sept 14, 2015, producing ~10⁻¹⁸ m arm displacements measured 7 ms apart by Hanford and Livingston.

Why it matters

1.3 billion years ago two black holes merged; the author says that in the final 20 milliseconds before merger three solar masses were converted to energy via E=mc², producing a peak power of ~3.6×10^49 W—about 50 times the combined luminosity of all stars in the observable universe—as gravitational waves.

Key details

  • The wave reached LIGO on September 14, 2015, stretching a 4 km interferometer arm by ~10⁻¹⁸ m (≈1/1,000 the width of a proton); Hanford and Livingston (≈3,000 km apart) recorded the signal 7 ms apart, an offset matching light travel time and narrowing the source to a southern-sky patch.
  • The author equates the measurement’s proportional precision to checking Alpha Centauri’s distance to within a human-hair width, notes the three-solar-mass energy release is described as occurring over ~200 milliseconds as well, and emphasizes Einstein predicted gravitational waves in 1915 but thought detection impossible.
Source evidence

The math on this detection should reset what powerful and precise both mean.

1.3 billion years ago, two black holes spiraled together. In the final 20 milliseconds before merger, three solar masses got converted to pure energy via E=mc². Peak output hit 3.6×10⁴⁹ watts. Fifty times the combined luminosity of every star in the observable universe. No light involved. The energy radiated as ripples in spacetime itself.

That wave traveled for 1.3 billion years. When it left, Earth had no animals and no plants on land, just microbial life. It kept moving while the Cambrian explosion happened, dinosaurs rose and fell, primates evolved, and humans figured out how to build lasers.

It arrived at LIGO on September 14, 2015 as a distortion that stretched a 4-kilometer arm by 10⁻¹⁸ meters. One-thousandth the width of a proton.

Two detectors 3,000 kilometers apart both registered it. The signal arrived 7 milliseconds apart, exactly the travel time of light between Hanford, Washington and Livingston, Louisiana. That offset alone narrowed the source to a patch of the southern sky.

Proportionally, the measurement equals checking the distance to Alpha Centauri to within the width of a human hair.

Three solar masses converted to energy in 200 milliseconds. Detected by watching spacetime breathe at the subatomic level.

Einstein predicted this in 1915. He also thought it could never be measured.

Bilim Dünyası (@dunyasalbilim)

Kütle çekim dalgalarının ilk doğrudan gözleminde, iki kara deliğin birleşme anı kaydedildi.
Bu birleşme sırasında ortaya çıkan enerji, gözlemlenebilir evrendeki tüm yıldızların yaydığı toplam ışıktan bile daha güçlüydü.

Video

— https://nitter.net/dunyasalbilim/status/2054064024141369820#m