White gnome are the exposed burn - out cores of dead stars that have run low through the red elephantine phase but are not heavy enough to gosupernova . This is the destiny of our Sun . astronomer have now announced a all weird white dwarf , which frisk two different faces . One side is covered in hydrogen , and the other one is covered in helium .
The objected is nickname Janus , after the two - present R.C. god of transition . It was discovered by the Zwicky Transient Facility ( ZTF ) and followed up by several telescopes ; they reveal that Janus rotates on its axis every 15 minutes , changing its brightness apace . Observations looking at the chemical composition of this dead star revealed the two very different sides .
“ The open of the white nanus completely changes from one side to the other , ” lead author Dr Ilaria Caiazzo , from Caltech , said in astatement . “ When I show the observations to citizenry , they are blown away . ”
An artist’s impression of what the white dwarf might look like as it rotates.Image credit: K. Miller, Caltech/IPAC
The whitened dwarf has a temperature of 35,000 degrees Celsius ( 63,000 degrees Fahrenheit ) and it is scotch scientist . It is not at all clean how a whitened dwarf might finish up with two unlike sides . There are several possibility that the team has offer and are seem to essay further . One of them is that Janus has been get a line undergo change , making the name even more meet .
“ Not all , but some white midget conversion from being hydrogen- to helium - dominated on their open , ” Caiazzo explain . “ We might have mayhap caught one such white-hot dwarf in the routine . ”
This might explain what they are date , but it is still not clear how the decided faces come to be . Multiple explanations swear on the potent magnetic field that can be make inwhite dwarfs .
“ magnetised bailiwick around cosmic body tend to be asymmetric , or stronger on one side , ” Caiazzo explain . “ Magnetic fields can forestall the mixing of material . So , if the magnetized field is impregnable on one side , then that side would have less mix and thus more hydrogen . ”
This is one possible action . But the magnetised field of operation can also recreate a part in more or less cumber the plasma around white-hot dwarfs , creating different atmospheric pressure and compactness in their atmospheres .
“ The magnetic field may lead to miserable gas pressures in the atmosphere , and this may allow a hydrogen ‘ ocean ’ to form where the magnetic field are inviolable , ” add co - source James Fuller , professor of theoretic astrophysics at Caltech . “ We do n’t know which of these theories are right , but we ca n’t think of any other way to explain the asymmetric sides without charismatic fields . ”
Janus is so far unique , but the team hop that it wo n’t remain so for long . They hope to useZTFto find more aim like Janus and see the mechanism that leave to its peculiar open physical composition .
The discipline is published inNature .
