Free Newsletters - Space - Defense - Environment - Energy - Solar - Nuclear
. 24/7 Space News .

Dwarf planet Makemake lacks atmosphere
by Staff Writers
Munich, Germany (SPX) Nov 22, 2012

This artist's impression shows the surface of the distant dwarf planet Makemake. This dwarf planet is about two thirds of the size of Pluto, and travels around the Sun in a distant path that lies beyond that of Pluto, but closer to the Sun than Eris, the most massive known dwarf planet in the Solar System. Makemake was expected to have an atmosphere like Pluto, but this has now been shown to not be the case. Credit: ESO/L. Calcada/Nick Risinger.

Dwarf planet Makemake [1] is about two thirds of the size of Pluto, and travels around the Sun in a distant path that lies beyond that of Pluto but closer to the Sun than Eris, the most massive known dwarf planet in the Solar System.

Previous observations of chilly Makemake have shown it to be similar to its fellow dwarf planets, leading some astronomers to expect its atmosphere, if present, to be similar to that of Pluto. However, the new study now shows that, like Eris, Makemake is not surrounded by a significant atmosphere.

The team, led by Jose Luis Ortiz (Instituto de Astrofisica de Andalucia, CSIC, Spain), combined multiple observations using three telescopes at ESO's La Silla and Paranal observing sites in Chile - the Very Large Telescope (VLT), New Technology Telescope (NTT), and TRAPPIST (TRAnsiting Planets and PlanetesImals Small Telescope) - with data from other small telescopes in South America [2], to look at Makemake as it passed in front of a distant star [3].

"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. This means that the little dwarf planet has no significant atmosphere," says Jose Luis Ortiz.

"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. Finding out about Makemake's properties for the first time is a big step forward in our study of the select club of icy dwarf planets."

Makemake's lack of moons and its great distance from us make it difficult to study [4], and what little we do know about the body is only approximate.

The team's new observations add much more detail to our view of Makemake - determining its size more accurately, putting constraints on a possible atmosphere and estimating the dwarf planet's density for the first time.

They have also allowed the astronomers to measure how much of the Sun's light Makemake's surface reflects - its albedo [5]. Makemake's albedo, at about 0.77, is comparable to that of dirty snow, higher than that of Pluto, but lower than that of Eris.

It was only possible to observe Makemake in such detail because it passed in front of a star - an event known as a stellar occultation. These rare opportunities are allowing astronomers for the first time to find out a great deal about the sometimes tenuous and delicate atmospheres around these distant, but important, members of the Solar System, and providing very accurate information about their other properties.

Occultations are particularly uncommon in the case of Makemake, because it moves in an area of the sky with relatively few stars. Accurately predicting and detecting these rare events is extremely difficult and the successful observation by a coordinated observing team, scattered at many sites across South America, ranks as a major achievement.

"Pluto, Eris and Makemake are among the larger examples of the numerous icy bodies orbiting far away from our Sun," says Jose Luis Ortiz. "Our new observations have greatly improved our knowledge of one of the biggest, Makemake - we will be able to use this information as we explore the intriguing objects in this region of space further."

[1] Makemake was initially known as 2005 FY9. It was discovered a few days after Easter in March 2005, earning it the informal nickname of Easterbunny. In July 2008 it was given the official name of Makemake. Makemake is the creator of humanity and god of fertility in the myths of the native people of Easter Island.

Makemake is one of five dwarf planets so far recognised by the International Astronomical Union. The others are Ceres, Pluto, Haumea and Eris. Further information about dwarf planets and planets is available from the International Astronomical Union.

[2] Another of the telescopes used in this observing campaign was an 0.84-metre telescope installed by the Catolica del Norte University of Chile. This telescope is sited on Cerro Armazones, the future site of the European Extremely Large Telescope (E-ELT).

[3] Makemake passed in front of faint star NOMAD 1181-0235723 (where NOMAD refers to the Naval Observatory Merged Astrometric Dataset) on 23 April 2011. The team observed this event using seven different telescopes across Brazil and Chile. The event only lasted about one minute, so the astronomers took advantage of a specialised high-speed camera known as ULTRACAM (eso0520) and a high-speed infrared imager named ISAAC to capture the event.

[4] In the case of objects that are orbited by one or more moons the motions of the moons can be used to deduce the mass of the object. This was not possible in the case of Makemake.

[5] The dwarf planet was calculated to have a geometrical albedo of 0.77 +/- 0.03, greater than Pluto's, but smaller than that of Eris. An albedo of 1 represents a perfectly reflecting body, and 0 a black surface that does not reflect at all. The observations, together with previous results, indicate that Makemake has a density of 1.7 +/- 0.3 grams per cubic centimetre, which in turn allowed the team to infer the shape and appearance of an oblate spheroid - a sphere flattened slightly at both poles - with axes of 1430 +/- 9 kilometres and 1502 +/- 45 kilometres. Makemake shows no global Pluto-like atmosphere at a level of one thousandth of that of Pluto's atmosphere. However, it may have an atmosphere that only covers part of the surface. Such a local atmosphere, which is possible in theory, is not excluded by the observations.

This research was presented in a paper "Albedo and atmospheric constraints of dwarf planet Makemake from a stellar occultation" to appear in the 22 November 2012 issue of the journal Nature. The team is composed of J. L. Ortiz (Instituto de Astrofisica de Andalucia, CSIC, Spain), B. Sicardy (Observatoire de Paris; CNRS; Universite Pierre et Marie Curie; Universite Paris Diderot; Institut Universitaire de France), F. Braga-Ribas (Observatoire de Paris, CNRS, France; Observatorio Nacional/MCTI, Brazil), A. Alvarez-Candal (European Southern Observatory, Chile; Instituto de Astrofisica de Andalucia, CSIC, Spain), E. Lellouch (Observatoire de Paris, CNRS, France), et al.


Related Links
The million outer planets of a star called Sol

Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks DiggDigg RedditReddit GoogleGoogle

Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News

At Pluto, Moons and Debris May Be Hazardous to New Horizons Spacecraft During Flyby
Laurel, MD (SPX) Oct 17, 2012
NASA's New Horizons spacecraft is now almost seven years into its 9.5-year journey across the solar system to explore Pluto and its system of moons. Just over two years from now, in January 2015, New Horizons will begin encounter operations, which will culminate in a close approach to Pluto on July 14, 2015, and the first-ever exploration of a planet in the Kuiper Belt. As New Horizons has ... read more

China's Chang'e-3 to land on moon next year

Moon crater yields impact clues

Study: Moon basin formed by giant impact

NASA's LADEE Spacecraft Gets Final Science Instrument Installed

Spacecraft Monitoring Martian Dust Storm

Meteorite samples provide definitive evidence of water and rock types on Mars

Curiosity Rover Preparing for Thanksgiving Activities

Curiosity Team May Reveal Major Discovery Soon

UK Secures Billion Pound Package For Space Investment

Europe, U.S. talk space program link

At Helsinki's Slush, start-ups 'speed date' for financing

NASA Selects Information Technology Flight Operations Support Contract

Mr Xi in Space

China plans manned space launch in 2013: state media

China to launch manned spacecraft

Tiangong 1 Parked And Waiting As Shenzhou 10 Mission Prep Continues

Three ISS crew return to Earth in Russian capsule

Station Crew Off Duty After Undocking

Space station command changes

Russia restores space contact after cable rupture

Pleiades 1B is ready for integration in the payload "stack" for Arianespace's next Soyuz mission

France, Germany compromise on Ariane launcher: minister

Mexsat Bicentenario is delivered to French Guiana for its December launch on Ariane 5

France, Germany seek Ariane compromise at ESA space meet

Rare image of Super-Jupiter sheds light on planet formation

Astronomers Directly Image Massive Star's 'Super-Jupiter'

NASA's Kepler Wraps Prime Mission, Begins Extension

Lowell astronomer, collaborators point the way for exoplanet search

Systems engineering expertise leads to increased counterfire target acquisition radar capabilities

Raytheon achieves critical firsts for US Navy dual-band radar

Thermogenerator from the Printer

University of Glasgow and Clyde Space set to put brakes on space junk problem

The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement