The Hubble Space Telescope has observedthe most distant star ever seen Earendel, meaning morning star.
Astronomers see into the deep past when we view distant objects.
So we are looking at events that happened in the past.
That is just 900 million years after the Big Bang.
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To see further back in time, the objects need to be very bright.
And the furthest objects we have seen are the most massive and brightest galaxies.
The brightest galaxies are ones with quasars luminous objects thought to be powered bysupermassive black holes in them.
Before 1998, the furthest detected quasar galaxies were about 12.6 billion years of lookback time.
Why look back?
The light was scattered by the charged particles, which made the universe a foggy soup.
As the universe expanded it cooled until eventually the electrons combined with the protons to form atoms.
This light has continued to travel across the universe until it reaches us today.
The wavelength of the light got longer as the universe expanded and we currently see it as microwaves.
This light is the CMB and can be seen uniformly at all points in the sky.
The CMB is everywhere in the universe.
Close up of Earendel.
There is a possibility, however, that we can one day see even beyond the CMB.
To do this we cannot use light we will need to usegravitational waves.
These are ripples in the fabric of spacetime itself.
If any formed in the fog of the very early universe, then they could potentially reach us today.
In 2015, gravitational waveswere detectedfrom the merging of two black holes using the LIGO detector.
