Astronomers late stumble upon a teeny star called2MASS J0523 - 1403located just 40 light years forth . It ’s not only the modest star discovered so far - it may also represent thesmallest possible star . By studying stars such as this , scientists are start out to be able to fix the question : where do star finish and brown dwarfs begin ?
Starsare burning balls of gas held together by gravitational attraction that are fuelled by the fusion of H speck to helium in their cores . wiz come in a variety of sizes ; the small star , known as red midget , can have as small as 10 % of the mass of our Sun , whereas the fully grown star ( hypergiants ) can be over 100 times as massive as the Sun . But just how small can an objective be and still be defined as a star ? This has nonplus astronomers for long time . All that was previously known is thatobjects below this limitdon’t have enough mass to inflame the fusion of hydrogen in their cores . These objects are hump as chocolate-brown dwarfs .
browned dwarfsare elusive objects that are thought to be the miss link between gas giants and humble - mass headliner such as red dwarfs . They ’re generally around the size of it of Jupiter , but they do n’t have enough mass to become a mavin . Unlike mavin , brown gnome have no intimate energy rootage .
There survive another unusual difference between chocolate-brown dwarfs and stars ; they haveopposite relationshipsbetween mass and size . The more material you add to a whiz , in the shape of hydrogen , the bigger the radius of the star . I.e. stars increase in size as mass increases . Brown dwarfs , on the other helping hand , really shrink in size with increasing mass because of something call electron degeneracy press .
So how do we feel the limit that dictate whether an object is a mavin or a brown nanus ? Astronomers scanned the sky andlocated objectsthat were cerebrate to lie in around the star / brown gnome border . They then calculated the luminosity , temperature and radii of all of these object and plat them . Temperature is dependent on mass but it ’s wanton to quantify . They found that as temperature decreased , so did radius ; this is the expected course for stellar aim . However , they found that after temperature of around 2100 K ( 1826oC [ 3320oF ] ) there was a break until radius bulge to increase with decreasing temperature ; this is the trend that would be expected for brown midget .
Thanks to this data , scientist can now nail the specific temperature , brightness level and radius at which the independent sequence ends . The primary successiveness is a relationship between luminosity and temperature ( and light and radius ) that is obeyed by star throughout the majority of their lives.2MASS J0523 - 1403is located around this boundary , but toward the stellar side . This star actually has a temperature of 2074 K , which is the lowest account temperature so far for a main chronological succession sensation . It ’s also thesmallest and the least monolithic ; if it had less mess then it would be a brown dwarf . This sensation has therefore been identified as a representative of the smallest possible genius . However , it is theoretically possible that a star with a slightly smaller mass than 2MASS J0523 - 1403 could subsist , but we have n’t found it yet .
Scientists believethat information such as this could help us in our search for life history on other planet . Brown nanus cool down much quicker than star , so their surrounding planets are belike not very habitable . Therefore acknowledge the temperatures of objects around the mavin / brown nanus bounds will assist astronomers in their search for candidates that could support habitable planets .
