The New Horizons probe detects excess light from the cosmic optical background

New mysteries in the cosmic optical background…in the journal physical review Lettersastronomers explained that the probe new Horizons NASA, which continues its journey to the outer reaches of the solar system, has captured twice as much light as expected. This excess may come from stars and galaxies that we cannot see. It could also be the mysterious dark matter!

Cosmic visual background light

The latest work uses data sent back by the New Horizons probe. They have enabled astronomers to obtain an accurate measurement of the optical background. The least we can say is that the results surprised them because they got higher values ​​than expected.

The cosmic optical background represents all the light produced by stars, galaxies, supernovae, and all objects throughout the history of the universe. In other words, the cosmic optical background light represents the combined light of all light sources in the universe.

We should not confuse the idea of ​​the cosmic visual background with cosmic microwave background, Also known as the cosmic microwave background. It is homogeneous electromagnetic radiation with an emission peak in the microwave range. This radiation would have been emitted about 380,000 years after the Big Bang. A time when the universe was much denser and hotter than today.

The Cosmic microwave background It can provide a huge amount of information about the first 400,000 years of the universe. For its part, the cosmic optical background tells the story of all the luminous objects in the universe that were then formed.

The results obtained when measuring the luminosity of this cosmic optical background amazed astronomers. They have already detected an excess of light. It is already double what they expected. To explain this excess of light, astronomers at Johns Hopkins University in Baltimore, US, put forward the idea that it is caused by the decay of dark matter into photons.

Read also: New Horizons probe exceeds the milestone of 50 astronomical units!

Dark matter, a mysterious mass in the universe

Astronomers analyzed the data received by LORRI. It’s a high-resolution imager aboard New Horizons. Thanks to this, they detected this extra light from the cosmic optical background.

The New Horizons probe is a NASA probe. It was launched on January 19, 2006 to study and explore the Plutonian system and the Kuiper belt. It is a region of the solar system. It extends beyond the orbit of Neptune at a distance of 30 to 55 AU from the Sun. A little over a year after its launch, the American probe flew by Jupiter. Then it began its long journey to Pluto, which it flew by in July 2015. 3 years ago, on January 1, 2019, it passed 3,500 km from Arrokoth. It is an object 33.5 km long and 19.5 km wide belonging to the Kuiper Belt.

Explain this phenomenon extra light from the cosmic optical background detected by d New Horizons probe It could provide an answer to the nature of dark matter, one of the strangest components of the universe. Cosmology has now proven it exists black matter. It is an electrically neutral substance, and it does not interact with ordinary matter. It is insensitive to electromagnetic force and therefore does not absorb, emit or reflect any light. So it is difficult to notice it, but it is felt by its attractiveness. We know that it is spread all over the universe. So it’s about 80% of all the stuff out there. One theory is that neutral elementary particles are called axions form dark matter.

Read also: 3 Discoveries on the asteroid Arrokoth

Mathematical modeling

For astronomers, these axes should have the same behavior as dark matter. Also, it seems the best way to detect them is through the photons they emit. In theory, when exposed to a strong magnetic field, axions disintegrate into pairs of photons. Scientists are facing a great difficulty. You should be able to separate these photons from all other sources of light in the universe.

Johns Hopkins University researchers used mathematical modeling. Thus, they determined that axions with masses between 8 and 20 electrons could be responsible for the excess light detected by New Horizons that comes from the cosmic optical background.

However, the data collected so far is insufficient to say that the axions come from the decay of dark matter into photons. Therefore, we cannot say that these axes explain this luminous surplus.

Currently, astronomers consider that the luminous objects of the universe that we cannot observe produce this excess of light. Perhaps other work will someday decide on the best possible explanation for this excess of light from the cosmic optical background.

Read also: What are the odds of measuring dark matter?