Astrophysicists scanning the heavens have clocked a new cosmological record: the two biggest black holes ever detected — one about 10 billion times the mass of our sun and the second as much as twice that mass.
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Using the Gemini North and Keck 2 telescopes in Hawaii, the McDonald Observatory in Texas and the Earth-orbiting Hubble space telescope, the scientists did more than luck out — they found the stars and gas near the centres of the two far-off galaxies were moving much faster than they had anticipated.
That meant the black holes were larger than they should be, even taking into account the large size of the galaxies they sat within.