AT 2017gfo

Transient

The first kilonova ever observed alongside gravitational waves, produced when two neutron stars merged and forged heavy elements including gold.

Facts

TypeTransient
Event typeKilonova
Distance from Earth130,000,000 ly
Apparent magnitude17.5
Redshift0.00973
Discovered2017

AT 2017gfo in context

The light reaching us from AT 2017gfo tonight left it around 130,000,000 years ago.

Of the 5 transients these pages cover, only 2 lie closer to us.

Its light arrives redshifted by z = 0.00973, stretched on the way here by the universe's expansion.

It has been on record since 2017.

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