Galaxies Colliding The Andromeda galaxy appears to be on a collision course with the Milky Way. Currently about 2.5 million light-years away from our galaxy, it is speeding toward us at about 110 kilometers per second. Yet some of that movement could be lateral, and Andromeda may end up whizzing by instead of colliding. Astronomers created computer simulations of the motions of both galaxies and ran them over and over, changing various variables each time, and calculated that the odds of Andromeda and Milky Way colliding <https://url364.scientificamerican.com/ls/click?upn=u001.D2t-2BQgIFPkkrqQirJgMRFAiBJHJONb-2BfdW5HE3yxLau8FAf2Pf9GjDh93LDBrw6FUuxkgw-2FYAMpmB73WojfbTj9daajA3gHNAdyzs2858JFcRLBwwNnShaa6AmcuIUaH-2FcCjisGj3SgXulueLz4dTQ-3D-3DLATp_JtI4-2FxU1EszqK01Y8-2FaZPD1mDRs7gd0v1oSSNlhk-2BDU-2FcJbinGa7-2FcQguEzpj57HMkaz677m174seUfQiSvUbUP5pIGbGyBEBOVqh7-2FCZrxghU4HqL2zCNSBNtdwGxaJ-2BrdFqunR6tUEtTBJTdjzfIDLOqWgjiDK5IxlfZLVGumAZi-2FUAnHSaubPjpm8uD4EFtjqLAGatA9N-2BA-2FW6f-2F-2FwwSDH1mgSnD8w3Rh6C7IxdDgf240z9tZvPY5y8Aqs6jP4aMGJ8mM4DB3AS3JY0frNfoxnBRMUHaXXyOVGQI3sNHiKWOGzTB8RrHmIKhIcwddqUc0XcwmuhQAMFRzSw0zZhXH03JHpKHL1njuTHesfZfVohaSrQkaLU2Y2ntf8OuOKL09Hr0aFjyp9l-2BXEvezfAJamzMpfzmsqlvY8tXvdnZ4kCqozOcNjfLLHj5eoBD0YdgL8bux90iuFcQo1uLEAKWoIIY2zioDWY4kSGi0v8YIDlT3wSOYUPvmSUL0-2FOPfFt6IGY38C9oEZiZshN2CbPEQldaWYiP4i4V-2B716HEQSNYGy8BnQB8PNbjkK-2BV646UrNRvCKMKrVq-2FPCOxUoZRR7vl20HkrZpYCnGReZcF0CyYeWLrTWqK9pV-2Ftgr0zZwfebfwQdGnRya39HCfQuy3o3D5v1HM6vtYo7Kj1iHOklVL-2BB8jTyoRS9rbOQriSeZNMu45rnG5kx-2BTEfDK6FDcNbc3pW1SuW47x5LptmgTG2hQCwjSyPHqrqzbfLfB44ce8tngFXaueCpZihFl7jP6D3J5LSMnSpN56BpeSpoiRynvNa6GV0pN8fBME6D5D9MWWTS3GD2BiB-2B-2BT-2FXhzOHE9BWHofWbZS4q-2BBy6L7hV99pkJ4bq3HkJPLaFb8-2F8dTqeKXO8OUMU5driYuc2-2F8lqw-3D-3D> is about 50 percent.
*How it works:* The collision of two galaxies is a long dance that takes about a billion years to complete. Two galaxies usually pass closely to each other, each stretching like taffy as their gravitational pulls clutch at each other, writes astronomer and columnist Phil Plait. That stretching decreases their orbital energy, so that they circle back around and slam into each other some time later, merging into a new elliptical galaxy. *What the experts say:* Such a collision would not occur for 8 billion years, so rest easy, Plait says. Plus, many variables (like the gravitational pull of *other* galaxies in the area) may prevent collisions. “Collisions and mergers such as this are how galaxies grow. The Milky Way is a bruiser among galaxies, and we got here by what is essentially galactic cannibalism.” Eyes on Task Pupil size can indicate cognitive power. In a recent study, participants looked at a sequence of numbers that each flashed on a screen for 2.5 seconds. They then had to indicate whether the current digit matched a number they had seen two digits earlier in the sequence. Participants whose pupils dilated more performed better <https://url364.scientificamerican.com/ls/click?upn=u001.D2t-2BQgIFPkkrqQirJgMRFAiBJHJONb-2BfdW5HE3yxLau8FAf2Pf9GjDh93LDBrw6F8V8n6eO4WuN4TU-2BO46y3J2-2FhBWb0-2BidrG11nPkPGVFPghbvg0Q-2Fw1dFWP30M2-2BOiaYSh5WpItCJlgH12gz8OGA-3D-3DCdC8_JtI4-2FxU1EszqK01Y8-2FaZPD1mDRs7gd0v1oSSNlhk-2BDU-2FcJbinGa7-2FcQguEzpj57HMkaz677m174seUfQiSvUbUP5pIGbGyBEBOVqh7-2FCZrxghU4HqL2zCNSBNtdwGxaJ-2BrdFqunR6tUEtTBJTdjzfIDLOqWgjiDK5IxlfZLVGumAZi-2FUAnHSaubPjpm8uD4EFtjqLAGatA9N-2BA-2FW6f-2F-2FwwSDH1mgSnD8w3Rh6C7IxdDgf240z9tZvPY5y8Aqs6jP4aMGJ8mM4DB3AS3JY0frNfoxnBRMUHaXXyOVGQI3sNHiKWOGzTB8RrHmIKhIcwddqUc0XcwmuhQAMFRzSw0zZhXH03JHpKHL1njuTHesfZfVohaSrQkaLU2Y2ntf8OuOKL09Hr0aFjyp9l-2BXEvezfAJamzMpfzmsqlvY8tXvdnZ4kCqozOcNjfLLHj5eoBD0YdgL8bux90iuFcQo1uLEAKWoIIY2zioDWY4kSGi0v8YIDlT3wSOYUPvmSUL0-2FOPfFt6IGY38C9oEZiZshN2CbPEQldaWYiP4i4V-2B716HEQSNYGy8BnQB8PNbjkK-2BV646UrNRvCKMKrVq-2FPCOxUoZRR7vl20HkrZpYCnGReZcF0CyYeWLrTWqK9pV-2Ftgr0zZwfebfwQdGnRya39HCfQuy3o3D5v1HM6vtYo7Kj1iHOklVL-2BB8jTyoRS9rbOQriSeZNMu45rnG5kx-2BTEfDK6FDcNbc3pW1SuW47x5LptmgTG2hQCwjSyPHqrqzbfLfB44cmQLcG6eehoxtNFufGSZCrWLdYk7Dt2hskcLtke4rRGgY8p7atgrqhnOLSPvZ6ok2hRpGv9PdIrERmfj5TQ-2FNLpmxSTivSeDsGPWGJLpE5uwFtSG-2BTw49UzGKLdYJK6ezw-2FtTn-2FI-2BsexMxGhjzhMPlw-3D-3D> on the task. *How it works:* People who were better able to identify the correct number devoted more intense attention (indicated by their increased pupil diameter) more consistently (indicated by less variation in their pupil size). The results align with the so-called intensity-consistency framework: People who more consistently and intensely devote their attention toward a task perform that task better. *What the experts say:* Tracking the link between cognitive performance and pupil size could be a useful research tool since it’s noninvasive, says neuroscientist Andreas Tolias of Stanford University. “Finding these correlations with performance is yet another indication that pupil measurement is very important.” KR IRS 23824 SCIENCE TODAY -- You received this message because you are subscribed to the Google Groups "Thatha_Patty" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/thatha_patty/CAL5XZoogNETBeWmjC7DaTqOPjUmbaTJo1QLshu%2B_zS_JhjA2DA%40mail.gmail.com.
