NASA’s Hubble discovers farthest star detected till date: Earendel

Published: 9th Apr, 2022

Context

NASA’s Hubble Space Telescope has discovered the farthest star ever seen to date.

About

About the star:

The star is more than 9 billion light-years away.
It is likely existed within the first billion years after the beginning of the universe.
The star system is officially called WHL0137-LS.
It has been nicknamed “Earendel”, which means “morning star” in Old English.

Other record-holding star:

Icarus:
- This discovery is a massive leap from the previous record-holding star: “Icarus” or officially, MACS J1149+2223 Lensed Star 1.
- Icarus existed at a time when the universe was about 4 billion years old or about one-third of its current age, at a time that astronomers refer to as “redshift 1.5.”
- Scientists use the word “redshift” because as the universe expands, light from distant objects is stretched or “shifted” to longer, redder wavelengths as it travels toward us.
The oldest known star, nicknamed “Methuselah,” discovered by Hubble in 2013.
Hubble also holds the cosmic distance record for a galaxy. Its light took 13.4 billion years to reach Earth.

What made such farthest star visible?

It happened because of phenomenon of gravitational lensing.
Gravitational lensing occurs when a cluster of stars warps the fabric of space.
This creates a sort of massive magnifying glass that distorts and amplifies the light from distant objects behind it.
In the case of Earendel, this is caused by a huge galaxy cluster called WHL0137-08.
Scientists expect Earendel to remain highly magnified in the years to come when it can be observed by NASA’s new James Webb Space Telescope.
Webb has a high sensitivity to infrared light which will be useful when trying to learn more about the newly-discovered star because its light is redshifted to longer infrared wavelengths.

Hubble Space Telescope

It is named after the astronomer Edwin Hubble.
The observatory is the first major optical telescope to be placed in space and has made ground-breaking discoveries in the field of astronomy since its launch (into Low Earth orbit in 1990).
It is said to be the “most significant advance in astronomy since Galileo’s telescope.”
It is a part of NASA's Great Observatories Program - a family of four space-based observatories, each observing the Universe in a different kind of light.
- The other missions in the program include the visible-light Spitzer Space Telescope, Compton Gamma-Ray Observatory (CGRO), and the Chandra X-Ray Observatory (CXO).

CURRENT AFFAIRS FOR UPSC IAS