Not much is known about Makemake, a dwarf planet that circles the Sun beyond Pluto. But scientists got a closer glimpse of it last year, when it passed briefly in front of a star (an event called an occultation), and they report their findings in the current issue of the journal Nature.
Nick Risinger/ESO
An artist's rendition of the surface of the distant dwarf planet Makemake. A new study now shows that?Makemake is not surrounded by a significant atmosphere.
Previously, researchers believed that because the surface temperature of Makemake (pronounced MAH-keh MAH-keh) is heterogeneous, it might have an atmosphere. ?If you have some patches with a higher temperature, the ice melts and creates vapor,? said an author of the new study, Noemi Pinilla-Alonso, a planetary scientist at the University of Tennessee. ?And with vapor the planet can develop an atmosphere around it.?
But the new measurements ? based on observations from multiple telescopes in different parts of South America ? indicate that Makemake, like another dwarf planet, Eris, does not have a significant atmosphere.
The researchers also determined that Makemake reflects about 77 percent of the Sun?s light, comparable to the reflection made by dirty snow, and that it is flattened at both poles.
Makemake occupies a portion of the solar system with very few stars, so a stellar occultation is rare, Dr. Pinilla-Alonso said.
?The fact that we could do this and record it with so many telescopes of different sizes is amazing,? she said.
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