Makemake is a dwarf planet in
the outer solar system. It was the fourth body identified as a dwarf planet,
and was one of the bodies that caused Pluto to lose its status as a planet.
Makemake
is large enough and bright enough to be studied by a high-end amateur
telescope. Astronomers took advantage of the dwarf planet's recent passage in
front of a star — called an occultation — to determine that Makemake has no
atmosphere.
TIME
Explains: 'Makemake' — A New Discovery in Our Solar System
Discovery and naming
Makemake
(pronounced mah-kee-mah-kee) was first observed in March 2005 by a team of
astronomers at the Palomar Observatory. Officially known as 2005 FY9, the tiny
planetoid was nicknamed Easterbunny by the group. The team was also responsible
for the discovery of dwarf planet Eris and involved in the controversial
discovery of the dwarf planet Haum.
By NASA
Makemake
|
Average Solar Distance
|
6.85 billion km
|
|
Revolution Period
|
309.88 Earth years
|
|
Rotation Period
|
unknown
|
|
Equatorial diameter
|
1500 km
|
|
0.048 times that of the Earth
|
|
|
Natural Satellites
|
0
|
Makemake (pronounced mah-kee-mah-kee) is named
after the god of fertility in Rapanui mythology. The Rapanui are the native
people of Easter Island . Easter Island is
located in the southeastern Pacific Ocean, 3600 kilometers off the coast of Chile
After Eris and Pluto,
Makemake is the third largest known dwarf planet. Along with fellow dwarf
planets Pluto and Haumea, Makemake is located in the Kuiper Belt, a region
outside the orbit of Neptune . Pluto
and Makemake are the two brightest objects that have so far been discovered in
the Kuiper Belt. It takes 310 Earth years for this dwarf planet to make one
orbit around the Sun.
Makemake was first observed
in 2005 by a team of astronomers led by Michael Brown. Its codename was
Easterbunny. It was officially recognized as a dwarf planet by the
International Astronomical Union in 2008. Observations have found evidence of
frozen nitrogen on Makemake's surface. Frozen ethane and methane have also been
detected on the surface. In fact, astronomers believe the methane may actually
be present in pellets as large as one centimeter in diameter. Astronomers also
found evidence of tholins. Tholins are molecules that form whenever solar ultraviolet light interacts with substances such as
ethane and methane. Tholins, if present, usually cause a reddish-brown color.
During observations of Makemake, a reddish color was observed.
................................
SCIENCE
& ENVIRONMENT
21 November 2012 Last updated at 18:01 GMT
Dwarf
planet Makemake examined for the first time
Astronomers have obtained an important first look at the dwarf
planet Makemake - finding it has no atmosphere.
One of five such dwarfs in our Solar System
including former planet Pluto, Makemake had until now eluded study. But in
April 2011, it passed between the Earth and a distant star, and astronomers
used seven telescopes to study how the star's light was changed. A report
in Nature outlines how they unpicked Makemake's size, lack of atmosphere, and
even its density.
 |
| An artist's impression shows the rocky world, distant from the Sun and lacking any obvious atmosphere |
Few battles in the astronomy community are as
fierce as the one surrounding the demotion of the planet Pluto from planet
status in 2006 to one of what the International Astronomical Union then dubbed
"dwarf planets".
Pluto shares the category with four other
little worlds: Ceres, Haumea, Eris and Makemake. Ceres, as the only inner
Solar System dwarf, has been analysed directly with telescopes. The far more distant Eris and Haumea have both been
analysed separately in the same kind of "occultation" that has now
given clues as to Makemake's makeup. Haumea was shown to be icy like Pluto, while Eris added to Pluto's indignities by ousting it as the largest dwarf.
Now Makemake has come under scrutiny by an
international team led by Jose Luis Ortiz of the the Andalucian Institute of
Astrophysics in Spain ,
making use of seven different telescopes across Brazil
and Chile
The dwarf was known to be about two-thirds the
size of Pluto, but the team put the measurement on a firmer footing, measuring
it to be not quite spherical - about 1,430km across in one direction and
1,500km across the other.
The team estimates that Makemake has a density
of 1.7 grams per cubic centimetre (similar to that of Pluto, but still less
than a third that of Earth) - but the key test was that of the dwarf planet's
atmosphere.
"As Makemake passed in front of the star
and blocked it out, the star disappeared and reappeared very abruptly, rather
than fading and brightening gradually," said Dr Ortiz.
"This means that the little dwarf planet
has no significant atmosphere. It was thought that Makemake had a good chance
of having developed an atmosphere - that it has no sign of one at all shows
just how much we have yet to learn about these mysterious bodies.
************
IAU0806: FOR IMMEDIATE RELEASE ************
Fourth
dwarf planet named Makemake
17 July
2008, Paris: The International Astronomical Union (IAU) has given the name Makemake to the newest member of the family of dwarf
planets — the object formerly known as 2005 FY9 —after the Polynesian creator of humanity and
the god of fertility.
Members of the International Astronomical
Union’s Committee on Small Body Nomenclature (CSBN) and the IAU Working Group
for Planetary System Nomenclature (WGPSN) have decided to name the newest
member of the plutoid family Makemake, and have classified it as the fourth
dwarf planet in our Solar System and the third plutoid.
Makemake (pronounced MAH-keh MAH-keh) is one
of the largest objects known in the outer Solar System and is just slightly
smaller and dimmer than Pluto, its fellow plutoid. The dwarf planet is reddish
in colour and astronomers believe the surface is covered by a layer of frozen
methane.
Like other plutoids, Makemake is located in a
region beyond Neptune that is
populated with small Solar System bodies (often referred to as the
transneptunian region). The object was discovered in 2005 by a team from
the California Institute of Technology led by Mike Brown and was previously
known as 2005 FY9 (or unofficially “Easterbunny”). It has the IAU Minor Planet
Center designation (136472). Once the orbit of a small Solar System body or
candidate dwarf planet is well determined, its provisional designation (2005 FY9 in the
case of Makemake) is superseded by its permanent numerical designation (136472)
in the case of Makemake.
The discoverer of a Solar System object has
the privilege of suggesting a name to the IAU, which judges its
suitability.
Mike Brown says: “We
consider the naming of objects in the Solar System very carefully. Makemake’s
surface is covered with large amounts of almost pure methane ice, which is
scientifically fascinating, but really not easily relatable to terrestrial
mythology. Suddenly, it dawned on me: the island of Rapa Nui
WGPSN and CSBN accepted the name Makemake
during discussions conducted per email.
Makemake holds an important place in the Solar
System because it, along with Eris and 2003 EL61, was one of the
objects whose discovery prompted the IAU to reconsider the definition of a
planet and to create the new group of dwarf planets. Visually, it is the second
brightest transneptunian object, following after Pluto, and is bright enough to
be seen through a high-end amateur telescope (a peak magnitude of roughly
16.5). Mike Brown explains: “The orbit is not particularly strange, but the object itself is
big. Probably about 2/3 the size of Pluto.”
The other three dwarf planets are Ceres, Pluto
and Eris. However, Ceres is not a member of the distinctive plutoid group
because its orbit is smaller than Neptune ’s (Ceres is located in the asteroid belt between Mars and
Jupiter).
The word Makemake is Polynesian in origin and
is the name of the creator of humanity and the god of fertility in the
mythology of the South Pacific island of Rapa Nui or the Easter Island . He
was the chief god of the Tangata manu bird-man cult and was worshiped in the
form of sea birds, which were his incarnation. His material symbol was a man
with a bird’s head.
Notes
The IAU is the international astronomical
organisation that brings together almost 10,000 distinguished astronomers from
all nations of the world. Its mission is to promote and safeguard the science
of astronomy in all its aspects through international cooperation. The IAU also
serves as the internationally recognised authority for assigning designations
to celestial bodies and the surface features on them. Founded in 1919, the IAU
is the world’s largest professional body for astronomers.
For more information, please contact:
Dr. Edward L.G. Bowell
IAU Division III President
Tel: +1-928-774-3358
Cell: +1-520-491-0710
E-mail:
elgb@lowell.edu
Mike Brown
Professor of Planetary Astronomy
California Institute of Technology
Phone: +1-626-395-8423
Lars Lindberg Christensen
IAU Press Officer
ESA/Hubble, Garching , Germany
Phone: +49-89-32-00-63-06
Cellular: +49-173-3872-621
Links
Scientific paper estimating the size of
Makemake: http://arxiv.org/abs/astro-ph/0702538v1
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