Neutron Stars Crashes Can Help Us Calculate Our Universe Expanding Rate

Aadhya Khatri - Feb 26, 2019

By using the LIGO, astronomers can tell how far the collision is from Earth and with the bright flash it generates, they can measure the system’s speed.

Survey Neutron Stars might help us know the speed at which the universe’s size is increasing. The year 2017 saw the first observation of a collision of two stellar objects. The result was a flash as bright as a billion suns in total and gravitational waves, disturbances in the curvature of space-time.

A neutron star collision

The waves are detected by LIGO (short for Laser Interferometer Gravitational-Wave Observatory in the US) while the crash was 130 million light years far from us.

This precious incident provided solid proof for the gamma-ray burst theory and an end for the debate of where gold and other elements come from. However, now, astronomers think that the collision can tell us more than that.

Research published on Physical Review Letters revealed that by studying the gravitational waves generated by these crashes, astronomers can finally have an answer for the question of at what speed the universe is increasing in size.

Before this finding, scientists have used other methods to calculate this rate, which is called the Hubble constant. However, the results they came up with were different from each other. This rose the concern of whether what we know of the universe and its final fate was accurate.

It was not until the observation of neutron stars’ collision that we came to a more reliable result.

The Hubble constant was named after Edwin Hubble

According to cosmologist Stephen Feeney, by studying 50 of such crashes, the best way to calculate the Hubble constant was found. He also shared that the time they needed to finish the calculation was about 5 to 10 years.

By using a system like the LIGO, astronomers can tell how far the collision is from Earth and with the bright flash it generates, they can measure the system’s speed. This information paired with the Hubble-Lemaitre Law can result in the Hubble constant. The team also came up with the number of crashes we need, which is only 50 collisions.

Hiranya Peiris, another member of the team said that this finding could help us determine how fast the universe is growing and enhance our current cosmological model.