Scientists Say There Are Likely Fewer Galaxies in Space Than They Previously Thought
While NASA previously determined that there were around two trillion galaxies in the universe, new findings say the number is more likely hundreds of billions.
The outside world, or universe in this case, just got a little clearer. Scientists recently took a deep dive into some unusual sightings out in the solar system, and their findings have to do with everything from the actual number of galaxies in the universe to the types of stars around us. Back in April 2020, NASA first detected a huge flare from its satellites that passed by Mars, and while this intergalactic sighting lasted for a mere 140 milliseconds, a research team in University of Johannesburg now knows that this was a burst from a magnetar, which is a powerful neutron star with a magnetic field. It originated in a galaxy 11.4 million light-years away in space, the Daily Mail reports.
Soebur Razzaque, a professor from the University of Johannesburg, noted that this sighting isn't too unlikely since there are tens of thousands of neutron stars in the Milky Way, but there are still just 30 that have been uncovered as magnetars. "Magnetars are up to a thousand times more magnetic than ordinary neutron stars," he explained. "Most emit X-rays every now and then. But so far, we know of only a handful of magnetars that produced giant flares. The brightest we could detect was in 2004." There is a chance that if another is spotted close to the Milky Way, that a radio telescope, like the MeerKAT in South Africa, researchers can learn even more about the inner workings of some of the most powerful forces in space. "That would be an excellent opportunity to study the relationship between very high energy gamma-ray emissions and radio wave emissions in the second explosion," Razzaque adds. "And that would tell us more about what works and doesn't work in our model."
When it comes to outer space as a whole, researchers have been busy discovering more than just stars. A new study in the Astrophysical Journal found that there actually might be fewer galaxies than previously thought; these findings stemmed from the team measuring the weak background glow from unseen galaxies, according to the Daily Mail. "It's an important number to know—how many galaxies are there? We simply don't see the light from two trillion galaxies," Mark Postman, a researcher from the Space Telescope Science Institute and a lead author of the study, said.
After doing more research, the team found that NASA's New Horizon spacecraft only detected hundreds of billions of galaxies instead of two trillion. Estimates before were found from NASA's Hubble Space Telescope, but the Hubble mainly uses mathematical models to discover galaxies due to the telescope's inability to see enough in visible light because of space pollution. There will still be a follow-up study to confirm these findings, though: "NASA's upcoming James Webb Space Telescope may be able to help solve the mystery," the team shared in a statement. "If faint, individual galaxies are the cause, then Webb ultra-deep field observations should be able to detect them."