New model of Solar system’s protective bubbleDate: 23 March 2020 Tags: Space
Boston University astrophysicist and collaborators reveal a new model of our heliosphere that’s shaped somewhere between a croissant and a beach ball.
The heliosphere is a vast region, extending more than twice as far as Pluto. It casts a magnetic “force field” around all the planets, deflecting charged particles that would otherwise muscle into the solar system and even tear through DNA.
The heliosphere, despite its name, is not actually a sphere. Space physicists have long compared its shape to a comet, with a round “nose” on one side and a long tail extending in the opposite direction.
In 2015, using a new computer model and data from the Voyager 1 spacecraft, researchers came to a different conclusion: they proposed that the heliosphere is actually shaped like a crescent, not unlike a freshly baked croissant, in fact. In this “croissant” model, two jets extend downstream from the nose rather than a single fade-away tail.
By timing particles echoing off the boundary of the heliosphere and correlating them with ions measured by the twin Voyager spacecraft, Cassini scientists concluded that the heliosphere is actually very nearly round and symmetrical: neither a comet nor a croissant, but more like a beach ball.
Unlike most previous models, which assumed that charged particles within the solar system all hover around the same average temperature, the new model breaks the particles down into two groups.
First are charged particles coming directly from the solar wind. Second are what space physicists call “pickup” ions. These are particles that drifted into the solar system in an electrically neutral form.
Researchers studying exoplanets–planets around other stars are keenly interested in comparing our heliosphere with those around other stars. Because they believe it holds recipe for formation of life.
Researchers are still working on DNA-shredding interstellar particles and what they mean for life on Earth and on other planets.
- Researchers are hoping to stir NASA to launch a next-generation interstellar probe that will cut a path through the heliosphere and directly detect pickup ions near the heliosphere’s periphery.