Astronomers have found a way to determine the center of mass of our solar system as low as 100 meters (330 feet), a new study reports.
Such precision, equivalent to the width of a human hair on the scale of a soccer field, could substantially help the search for powerful gravitational waves that deform our Milky Waystudy team members said.
Astronomers have typically located the center of mass of our solar system, or barycenter, by carefully tracking the motion of planets and other bodies orbiting the sun. Such work has revealed that the barycenter is in constant motion; it can be near the center of the sun, beyond its scorching surface or almost anywhere in between, depending on the positions of the planets.
Related: Our solar system: a photographic tour of the planets
But these earlier calculations are compromised by an imperfect understanding of planetary motion, specifically that of Jupiter, which is the gravitational second-in-command of the solar system. In the recent study, the researchers took a new approach, analyzing observations of pulsars made over more than a decade by the Nanohertz Observatory of North America for gravitational waves (NANOGrav) draft.
Pulsars they are rapidly spinning neutron stars, superdense stellar corpses that pack a lot of mass into a city-sized sphere. Pulsars emit radiation beams continuously from their poles. These rays seem to pulse (hence the name) because astronomers can only detect radiation when it points to Earth.
NANOGrav closely monitors pulsars using radio telescopes, primarily the large ones at the Arecibo Observatory in Puerto Rico and the Banco Verde Observatory in West Virginia. Pulsars are incredibly consistent, so any deviation in the usual timing of their beams arriving here on Earth could be evidence of deformation by gravitational waves, the space-time waves first predicted by Albert Einstein a century ago.
the Gravitational Wave Laser Interferometer Observatory The project (LIGO) carried out the first direct detection of gravitational waves in 2015 and has considerably increased its count in the following years. Most of the detected waves were generated by merging black holes, but two of the events involved the collision of neutron stars.
In general, LIGO is designed to find short-period gravitational waves generated by relatively low-mass objects spiraling towards each other. A Detection April 2019For example, it dates back to two neutron stars that together housed only 3.4 times the mass of our sun.
NANOGrav chases the biggest fish: long-period waves generated by the merger of supermassive black holes, the light-engulfing monsters that lurk at the heart of galaxies and can hold billions of solar masses. Detecting and studying such waves could shed considerable light on the evolution of galaxies and the relationship between galaxies and their central black holes, project team members have said.
And determining the center of mass of our solar system is a key part of that effort.
“Using the pulsars we observe in the Milky Way galaxy, we are trying to be like a spider sitting in stillness in the middle of its web,” study co-author Stephen Taylor, assistant professor of physics and astronomy at Vanderbilt University at Tennessee, he said in a statement. “How well we understand that the barycenter of the solar system is critical when we try to feel even the smallest tickle on the net.”
So the recent study, which was published in The Astrophysical Journal in April, may end up being a step on the road to groundbreaking discovery.
“Our accurate observation of pulsars scattered across the galaxy has located us in the cosmos better than ever,” said Taylor. “By finding gravitational waves in this way, in addition to other experiments, we get a more holistic view of all the different types of black holes in the universe.”
Mike Wall is the author of “Out There” (Grand Central Publishing, 2018; illustrated by Karl Tate), a book on the search for extraterrestrial life. Follow him on Twitter @michaeldwall. Follow us on Twitter @Spacedotcom or Facebook.
