International Space Agencies – Missions and Discoveries

CIBER-2 Mission to count the stars in the Universe


From UPSC perspective, the following things are important :

Prelims level : CIBER 2 Mission

Mains level : NA

A NASA-funded rocket’s launch window will open at the White Sands Missile Range in New Mexico, USA. The aim of this mission is to count the number of stars that exist in the Universe.

Answer this PYQ from CSP 2020 in the comment box:

Q.“The experiment will employ a trio of spacecraft flying in formation in the shape of an equilateral triangle that has sides one million kilometers long, with lasers shining between the craft.” The experiment in question refers to

(a) Voyager-2

(b) New horizons

(c) Lisa Pathfinder

(d) Evolved LISA

What is CIBER-2?

  • In order to roughly estimate the number of stars in the Universe, scientists have estimated that on average each galaxy consists of about 100 million stars, but this figure is not exact.
  • The figure of 100 million could easily be an underestimation, probably by a factor of 10 or more.
  • To put this into perspective, an average of 100 million stars in each galaxy (there an estimated 2 trillion of them as per NASA), would give a total figure of one hundred quintillion stars or 1 with 21 zeroes after it.
  • NASA notes that if this figure is accurate, it would mean that for every grain of sand on Earth, there are more than ten stars.
  • But this calculation assumes that all stars are inside galaxies, which might not be true and this is what the CIBER-2 instrument will try to find out.

How will CIBER-2 count stars?

  • NASA notes that the instrument will not actually count individual stars but it will instead detect the extragalactic background light
  • It is all of the light that has been emitted throughout the history of the Universe.
  • From all of this extragalactic background light, the CIBER-2 will focus on a portion of this called cosmic infrared background, which is emitted by some of the most common stars.
  • Essentially, this approach is aiming to look at how bright this light is to give scientists an estimate of how many of these stars are out there.
  • The ESA infrared space observatory Herschel also counted the number of galaxies in infrared and measured their luminosity previously.
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rashi jain
rashi jain
3 months ago


Nikhil Bhatia
Nikhil Bhatia
3 months ago
Reply to  rashi jain