Seasons Discovered on Neptuneís Moon Triton
The thin atmosphere of Neptuneís moon Triton varies in thickness with the seasons and in the throes of summer, despite its relatively large distance from the sun compared to other bodies in the solar system, new observations have found.
The European Southern Observatoryís Very Large Telescope, located in Chile, made infrared observations of Triton which show that summer is in full swing in the moonís southern hemisphere, and that the warmth of the summer sun causes Tritonís thin atmosphere to thicken.
"We have found real evidence that the sun still makes its presence felt on Triton, even from so far away," said Emmanuel Lellouch of the Observatoire de Paris in France and a member of the team that made the discovery.
The telescope also discovered the presence of carbon monoxide in Tritonís atmosphere and made the first ground-based detection of methane on the Neptunian moon.
Triton, Neptuneís largest natural moon, was the last solid object visited by the Voyager 2 spacecraft on its epic 10-year tour of the outer solar system. This view of Triton was made from topographic mapping of images obtained by Voyager. Credit: NASA/JPL/Universities Space Research Association/Lunar & Planetary Institute.
Of Neptuneís 13 moons, Triton is by far the largest, and, at about 1,700 miles (2,700 km) in diameter (or three quarters of the diameter of the Earthís moon), is the seventh largest moon in the whole solar system.
Since its discovery in 1846, Triton has fascinated astronomers because of its geologic activity, the many different types of surface ices, such as frozen nitrogen as well as water and dry ice (frozen carbon dioxide), and its unique retrograde motion (which means it rotates around its planet in the opposite direction of its planetís rotation).
On Triton, where the average surface temperature is about minus 391 degrees Fahrenheit (minus 235 Celsius), it is currently summer in the southern hemisphere and winter in the northern.
As Tritonís southern hemisphere warms up, a thin layer of frozen nitrogen, methane, and carbon monoxide on Tritonís surface sublimates into gas, thickening the icy atmosphere as the season progresses during Neptuneís 165-Earth-year orbit around the sun.
A season on Triton lasts a little over 40 years, and Triton passed the southern summer solstice in 2000.
Based on the amount of gas measured, Lellouch and his colleagues estimate that Tritonís atmospheric pressure may have risen by a factor of four compared to the measurements made by Voyager 2 in 1989, when it was still spring on the giant moon. The atmospheric pressure on Triton is now between 40 and 65 microbars ó 20,000 times less than on Earth.
Carbon monoxide was known to be present as ice on the surface, but Lellouch and his team discovered that Tritonís upper surface layer is enriched with carbon monoxide ice by about a factor of ten compared to the deeper layers, and that it is this upper "film" that feeds the atmosphere.
While the majority of Tritonís atmosphere is nitrogen (much like Earthís, which is 78 percent nitrogen), the methane in the atmosphere, first detected by Voyager 2, and only now confirmed in this study from Earth, plays an important role as well.
"Climate and atmospheric models of Triton have to be revisited now, now that we have found carbon monoxide and re-measured the methane," said team member Catherine de Bergh, also of the Observatoire de Paris.
The new observations of Tritonís atmosphere are detailed in the March 15 issue of the journal Astronomy & Astrophysics.
Pluto, often considered a cousin of Triton and with similar conditions, is receiving renewed interest in the light of the carbon monoxide discovery, and astronomers are racing to find this chemical on the even more distant dwarf planet.
Article from: Space.com
Voyager 2 flyby Animation - Neptune and Triton (1989)
Video from: YouTube.com
Neptuneís moon Triton - Interesting Facts
Video from: YouTube.com
Real Sound of Neptune - New Voyager Recording ;)
Global Warming on Mars, Pluto, Triton and Jupiter
Does gravity change with the seasons?
Hubble shows Pluto "turning red" - Planet X?
Scientists discover Earth-like, water-rich planet: study
Earth-like planet discovered outside solar system
Suicidal planet seems on death spiral into star
Mars May Still Be A Living Planet, Methane In Atmosphere Reveals
NASA uses probes to hunt for ancient planet that may prove Earth moon origins
Obamaís Plan To "Geo-Engineer" The Planet Mirrors CFR Policy Documents
Odd Cloud on Neptune Seen Splitting Into Two
Latest News from our Front Page
Estonia must accept African & Middle Eastern immigrants says politician
Kalle Laanet, an Estonian politician, spoke at the International Migration Forum held in Tallinn. He told the audience that the question is not: Should Estonia take the African and the Middle Eastern immigrants (who illegally entered Southern Europe)? He said the question is: How will Estonia take the immigrants?
‚ÄúToday the issue is not whether Estonia should receive the refugees coming to ...
Rescuing Palmyra: History's lesson in how to save artefacts
With Islamic State militants now inside the historic town of Palmyra in Syria, the question, inevitably, is whether they will destroy the ancient ruins.
As IS continues to sweep through parts of Iraq and Syria, damage to centuries-old artefacts - because IS sees statues and shrines as idolatrous - is plentiful.
But history has shown that, when culturally important sites are under ...
Saudi Arabia Wants to Convert Sweden to Islam
Aje Carlbom is an Associate Professor of Social Anthropology, University of Malmö
Since the 1970s, Saudi Arabia has actively spread its interpretation of Islam, Wahhabism or Salafism, worldwide. It is the most literal version of Islam and affects many young Muslims, who regard society as a place to Islamize, writes social anthropologist Aje Carlbom.
Sweden's Foreign Minister Margot Wallstr√∂m was ...
Professor: If You Read To Your Kids, You're 'Unfairly Disadvantaging' Others
According to a professor at the University of Warwick in England, parents who read to their kids should be thinking about how they're "unfairly disadvantaging other people's children" by doing so.
In an interview with ABC Radio last week, philosopher and professor Adam Swift said that since "bedtime stories activities . . . do indeed foster and produce . . ...
If You Read About Conspiracies You're Just Like Osama Bin Laden Apparently
At its heart, the story of Osama bin Laden's time at his house in Abbottabad is surreal. The American image of bin Laden - leering at us from under his head wrap as he plots and schemes - is undermined by the mundane realities of his life. The guy was responsible for murdering thousands of Americans and orchestrating a global ...
|More News » |