“ Moon over Makemake ” sounds like a novel or painting , but actually represents a NASA announcement of the discovery of a associate for the third largest ( and secondly brightest ) midget major planet in the Kuiper Belt . The proclamation strengthens the hypothesis that most dwarf planets have Moon , while also making Pluto wait slightly less special .
The Kuiper Belt stretches from Neptune ’s reach to 50astronomical units(AU ) from the Sun . Until 2000 , it was thought to turn back just Pluto , its lunation Charon , and some comet , but lately many new denizen have been disclose . moon have already been found aroundEris , the secondly expectant known resident physician of the swath , and smallerKuiper Belt Objects ( KBOs ) .
Now the Hubble Space Telescope has add S/2015 ( 136472 ) , nicknamed MK2 , to the list . So far very petty is have intercourse about MK2 . It is thought to be about 160 kilometers ( 100 mil ) across , and is about 1,300 times fainter than Makemake itself . However , its orbital characteristics are as yet unsung .
MK2 is hardly seeable above Makemake in this Hubble image . NASA , ESA , and A. Parker and M. Buie ( SwRI )
Once the orbit is measured we will be capable to calculate Makemake ’s mass ( using the fact that the orbital period calculate on space and heap ) . Since we already have a middling idea of Makemake ’s sizing , 1,500 kilometers ( 930 miles ) across , this will allow for an estimate of its density , and therefore composition . astronomer are keen to know how much it differs from Pluto , other than in size .
It is already known that Makemake , like Pluto , is spread over in frozen methane , but we know nothing about what consist beneath . Pluto has an mean distance of 39.5 AU from the Sun , while Makemake is 45.7 AU .
The orbit will also be declarative of MK2 ’s origins . An elongated field would hint that it is another KBO that Makemake captured at some full stop , while a nearly circular range would suggest that , like our own Moon , it is made of up detritus that was tap off in a hit with something with child .
Giant Earth - free-base telescopes can detect far fainter objects than the relatively small Hubble Telescope , but they have more difficulty finding something fainthearted when it is recede in the glower of a relatively shiny object like Makemake . In addition to this , Hubble may have got a little bit lucky with this observation , which was made in April 2015 but only just announce .
“ Our preliminary estimates show that the moon ’s orbit seems to be edge - on , and that means that often when you look at the organization you are going to leave out the moonshine because it gets drop off in the bright glare of Makemake , ” saidDr . Alex Parkerof the SouthWest Research Institute in astatement .
Makemake has puzzled astronomer antecedently , because it appear to have patches warmer than the rest of the icy humanity . However , it now seems likely that these “ patches ” were in fact detection of MK2 in telescopes ineffective to separate the two worlds . MK2 is warmer than its parent because its airfoil is very saturnine , ingest more heat . The deviation in color may be a result of MK2 receive too picayune gravity to hold onto the methane , which most of the time remains frosty on the surface of Makemake , but may sometimes turn to gas .
