What is the farthest object in space we have seen?

A2A

It’s a galaxy named GN-Z11, about 13.4 billion light years away.

When you look at the night sky, you’re actually looking into the past. It takes time for light from celestial objects to reach us. If a star explodes a light year away from us, it will take a year for it to be visible to our eyes.

Therefore, we can safely assume that GN-Z11 is at least 13.4 billion years old. That means, it was formed just 400 million years after our universe was formed.

What is more interesting is that GN-Z11 is 25 times smaller than our Milky Way. And such a small galaxy shouldn't have been able to exist when the universe was so young with our current understanding of cosmology.

It just goes to show how little we know about our early universe.

It's not an object per se, but I would say that it's the early cosmic soup from when the universe was only 380,000 years old. Anything we see in the universe we see through photons, and the photons that we've seen that have traveled the farthest are the photons from the cosmic microwave background radiation.

There was a point in time when the temperature of the universe dropped low enough so that the hydrogen plasma which made up all of the universe started to condense into neutral atoms. This allowed for these photons to travel free since those neutral atoms would no longer absorb the photons like the plasma would.

From that point in time, the universe has expanded a lot, which red-shifted the photons into the microwave range. That expansion also increased the distance between some of those photons and where the earth would eventually form. The photons from that radiation which are just reaching us now, have literally traveled as far as we can see; about 45.7 billion light years.

The Hubble Ultra-Deep Field (HUDF) is an image of a small region of space in the constellation Fornax, composited from Hubble Space Telescope data accumulated over a period from September 24, 2003, through to January 16, 2004. Looking back approximately 13 billion years (between 400 and 800 million years after the Big Bang) it will be used to search for galaxies that existed at that time. The HUDF image was taken in a section of the sky with a low density of bright stars in the near-field, allowing much better viewing of dimmer, more distant objects. The image contains an estimated 10,000 galaxies. In August and September 2009, the Hubble's Deep Field was expanded using the infrared channel of the recently attached Wide Field Camera 3 (WFC3). When combined with existing HUDF data, astronomers were able to identify a new list of potentially very distant galaxies

Reactions

Post a Comment

0 Comments