Current observations indicate that the universe is around 13.7 billion years old. We know that light takes time to travel, so that if us observe things that is 13 billion irradiate years away, then that light has actually been traveling towards us because that 13 exchange rate years. Essentially, we are seeing the object as it appeared 13 billion years ago.

You are watching: How many light years can we see

With each year that passes, ours newest an innovation enables united state to watch further and also further back.

The image used because that this protect against on our journey is the Hubble Ultra Deep ar (UDF). The UDF is among the deepest views of the visible world to date; absolutely it was the deepest once it to be originally developed in in 2003-2004. Over there are about 10,000 galaxies in this view, i m sorry is a kind of "core sample" of a very narrow job of sky close to the constellation Fornax. The smallest, reddest galaxies in the image, the which there are around 100, are amongst the most remote known objects!


UDF, Credit: NASA, ESA, S. Beckwith (STScI) and also the HUDF Team

The UDF looks earlier approximately 13 billion year (approximately between 400 and also 800 million years after the large Bang). Galaxies the existed in that time period would be an extremely young and very different in structure and also appearance than the cool spirals us see adjacent today.


Image Credits: UDF - NASA/ESA/S. Beckwith(STScI) and The HUDF Team. Because that UDF Location and also Age that the universe graphics: NASA

What is the Farthest recognized Object indigenous Earth?

Why infrared? due to the fact that the world is expanding; thus the farther earlier we look, the faster objects are relocating away indigenous us, i beg your pardon shifts their light in the direction of the red. Redshift way that light that is emitted as ultraviolet or visible irradiate is shifted more and an ext to red wavelengths.

The excessive distance of this newly uncovered galaxies method their light has actually been traveling to united state for an ext than 13 billion years, from a time once the world was much less than 4% the its current age.

Their discovery, i m sorry you deserve to read much more about in the NASA feature is exciting due to the fact that it could give united state an idea of exactly how abundant galaxies were close to the era once astronomers think galaxies first started forming. (Phil Plait has a great column around this exploration too.)


Credit: NASA, ESA, R. Ellis (Caltech), and also the UDF 2012 Team

As of this composing it appears that one of the galaxies in this current Hubble exploration may be a distance record breaker - it to be observed 380 million years after the large Bang, through a redshift of 11.9. This means the irradiate from this galaxy (pictured below) left 13.3+ billion light years ago.


Credit: NASA, ESA, R. Ellis (Caltech), and also the UDF 2012 Team

Just under a month ago, the existing candidate to be this object: a young galaxy dubbed MACS0647-JD. It"s only a tiny fraction of the dimension of our Milky method - and also was it was observed at 420 million years after the large Bang, as soon as the cosmos was 3 percent of its existing age that 13.7 exchange rate years. Come spot this galaxy, astronomers supplied the an effective gravity from the massive galaxy cluster MACS J0647+7015 come magnify the light from the far-off galaxy; this effect is called gravitational lensing.


Credit: NASA, ESA, M. Postman and also D. Coe (STScI), and the CLASH Team

Earlier in 2012, v the combined power of NASA"s Spitzer and also Hubble space Telescopes, and also the use of gravitational lensing, a team the astronomers spotted what could then have actually been the most far-off galaxy ever seen. Light from this young galaxy, MACS1149-JD, to be emitted as soon as our 13.7-billion-year-old universe was simply 500 million year old.


Credit: NASA, ESA, W. Zheng (JHU), M. Postman (STScI), and the CLASH Team

In 2010, a candidate for most distant galaxy was uncovered in the Hubble Ultra Deep Field. UDFy-38135539 is thought to it is in 13.1 billion irradiate years away. There is an ext information in this article on Phil Plait"s blog. I"ve supplied his labeled images:


The objects in the Hubble Ultra Deep ar may well be the farthest well-known objects, however there are various other contenders.

They include a galaxy called Abell 1835 IR1916, i m sorry was discovered in 2004, by astronomers from the European southern Observatory using a near-infrared tool on the Very big Telescope. The object is clearly shows to us because of gravitational lensing by the galaxy cluster Abell 1835, i beg your pardon is between this object and us. This galaxy is thought to be around 13.2 billion irradiate years away, which way it would day to about 500 million year after the big Bang. Note though, that this discover has no been verified by other instruments - the Spitzer room Telescope tried in 2006 without success.


Abell 1835 by the Hubble, Credit: NASA

Also in 2004, a team making use of both the Hubble room Telescope and the Keck Observatory found a galaxy the is believed to be about 13 exchange rate years away from us. The was discovered when observing the galaxy swarm Abell 2218. The irradiate from the far-off galaxy was visible due to the fact that of gravitational lensing. The very distant object is the one circled. For much more information, inspect out this press release.


Credit: European space Agency, NASA, J.-P. Kneib (Observatoire Midi-Pyrénées) and also R. Ellis (Caltech)

Then there"s the infrared James Webb room Telescope. If you recall, Hubble has actually near infrared capability, yet not mid-infrared, and for objects with an extremely high redshifts, to see these most far-off of objects would need a powerful telescope v mid-infrared capability. JWST will have the ability to see back to the first luminous objects to it is in born after ~ the big Bang.

In fact, one of JWST goals is to look even further back, to just 200 million year after the big Bang. One version of galaxy evolution has the very first galaxies developing then and also we require JWST to check this theoretical prediction!


Top panels: Hubble UDF. Bottom: Simulation the what a JWST Deep Field might look like. Credit: STScI

(Note: JWST will be able to see these very first galaxies there is no the aid of gravitational lensing; gravitational lensing might enable us to check out them better, however would not necessarily let us see further earlier in time.)

Distance Information

Some of the many newly detect objects may more than 13 billion light years away, as derived from a standard model of the Universe. However, a powerful brand-new generation the telescopes, choose the James Webb room Telescope, will certainly be essential to confirm the suspected distances of these objects.

When 13 billion irradiate years is interpreted into kilometers, there space a staggering number of zeros - the comes out to around 123,000,000,000,000,000,000,000 km.

See more: How Long To Thaw Frozen Turkey Breast In Fridge, How To Safely Thaw A Frozen Turkey

As time progresses, so will certainly our capability to check out futher and further away - providing us insight on the an extremely beginnings the the Universe"s existence!

How perform We Calculate ranges of This Magnitude?

At this distances, objects" redshifts room used, with and also extension the Hubble"s law to the remote Universe. Here, we have to know the history of how rapidly the cosmos was widening at each moment in time. This can be calculated native the quantity of normal and dark matter and of dark energy. Try Prof. Wright"s Javascript cosmology calculator at:

For much more information top top Hubble"s Law, please review the ar on finding distances to the Nearest Superclusters.

Why space These distances Important to Astronomers?

Scientists have approximated the age of the universe to be 13.73 billion years old (with an hesitation of about 120 million years). Once we observe an object that is 13 billion irradiate years away, us are essentially observing it as it was 13 billion years ago, when the cosmos was young. Being able to see and also thus hopefully recognize the at an early stage Universe is necessary to understanding how it was formed. If we see earlier far enough, maybe we will capture a glimpse of the first galaxies as they were just forming. Possibly we will someday be able to see the first starts forming. Could we see also further earlier than that? only time (and technology) will tell!

Travel Time

At the price of 17.3 km/sec (the rate Voyager is traveling away from the Sun), it would certainly take about 225,000,000,000,000 years to reach this distance. At the rate of light, it would take 13 exchange rate years!