An stargazer has predicted that our Sun may have many more close skirmish with other maven than we think , which may have major implications for life on Earth .
Coryn Bailer - Jones from theMax Planck Institute for Astronomyin Germany used datum from ESA ’s Gaia orbiter to monitor the motion of more than 300,000 sensation . From this , he then pose how a full number of 1 billion star in our wandflower might move over meter . Thefindingsare published in the journal Astronomy and Astrophysics .
He found that our Sun experience “ near ” encounters with between 490 and 600 star every million days . Close here is defined as 16.3 idle - old age ( 5 parsecs ) . For much close and potentially damaging meeting , 6.5 short - age ( 2 secpar ) , he foretell about 87 every million years , almost double previous estimates .
( While other principal like Proxima Centauri are within this range , it should be noted they are considerably down in mass than other stars predict to take on our Sun . )
The peril is that a passing lead could perturb theOort cloud , a region of comets think to extend up to a scant - class from our Sun . If the superstar is monolithic enough , or comes close enough , it could charge comet our agency , potentially causing extinction - level issue .
“ What ’s interesting is that because the rate of skirmish is quite high , there ’s in all likelihood a lot of comet being thrown into the Solar System all the clock time , ” Bailer - Jones told IFLScience .
“ Away from the Oort Cloud , what if some monolithic star near the closing of its life came nearby and went supernova ? That could have happened in the past , we have grounds for close supernova leave deposit on Earth . ”
Do n’t be too alarmed just yet , though , because there is n’t any grounds for impend encounters that might end life on Earth . Indeed , Bailer - Jones says that the risk of encroachment from near - Earth target ( NEOs ) like asteroids remain much higher .
But in about 1.3 million years , a dwarf star called Gliese 710 is expected to do quite close to Earth . Previous appraisal suggest it will pass only about 1 light - year aside . Gaia data , however , suggests this will be much close , perhaps only about a quarter of a light - year off , or 16,000 times the Earth - Sun space . This is well within the predicted realm of the Oort swarm .
( Bailer - Jones notes this update figure of speech was first spotted in the Gaia datum by a group of Polish astronomerslast year . His discipline substantiate the finding . )
Whether tightlipped encounters with other stars actually has an upshot on our Solar System is n’t clear . Some hypothesis suggest that passing ace could have been responsible for extinction effect on Earth , such as comet impacts or supernova . We do n’t have any direct evidence for this yet .
It ’s interesting to note , though , that the estimate of about 87 close encounters every million years stretch into the past times , as well as the future . It ’s probable , therefore , that we ’ve had plentitude of ancient visitors .
