The atmosphere of Pluto as observed by New Horizons.
نویسندگان
چکیده
Observations made during the New Horizons flyby provide a detailed snapshot of the current state of Pluto's atmosphere. Whereas the lower atmosphere (at altitudes of less than 200 kilometers) is consistent with ground-based stellar occultations, the upper atmosphere is much colder and more compact than indicated by pre-encounter models. Molecular nitrogen (N2) dominates the atmosphere (at altitudes of less than 1800 kilometers or so), whereas methane (CH4), acetylene (C2H2), ethylene (C2H4), and ethane (C2H6) are abundant minor species and likely feed the production of an extensive haze that encompasses Pluto. The cold upper atmosphere shuts off the anticipated enhanced-Jeans, hydrodynamic-like escape of Pluto's atmosphere to space. It is unclear whether the current state of Pluto's atmosphere is representative of its average state--over seasonal or geologic time scales.
منابع مشابه
New Horizons Pluto–Kuiper Belt mission: design and simulation of the Pluto–Charon encounter
The primary goal of the New Horizons Pluto–Kuiper Belt mission is to explore Pluto by 2020, before Pluto’s atmosphere collapses as predicted by scientists, and then explore the Kuiper Belt objects in an extended mission. The baseline mission plans to launch in January 2006, using a Jupiter gravity assist trajectory to reach Pluto. The New Horizons spacecraft will arrive at Pluto as early as 201...
متن کاملTHE NEW HORIZONS SOLAR WIND AROUND PLUTO (SWAP) OBSERVATIONS OF THE SOLAR WIND FROM 11–33 au
The Solar Wind Around Pluto (SWAP) instrument on National Aeronautics and Space Administrationʼs New Horizons Pluto mission has collected solar wind observations en route from Earth to Pluto, and these observations continue beyond Pluto. Few missions have explored the solar wind in the outer heliosphere making this dataset a critical addition to the field. We created a forward model of SWAP cou...
متن کاملNew Horizons: NASA’s Pluto-Kuiper Belt Mission
The New Horizons (NH) mission was selected by NASA in November 2001 to conduct the first in situ reconnaissance of Pluto and the Kuiper belt. The NH spacecraft was launched on January 19, 2006, received a gravity assist from Jupiter during closest approach on February 28, 2007, and is currently heading for a flyby encounter with the Pluto system. NH will study the Pluto system for nearly seven ...
متن کاملThe surface compositions of Pluto and Charon
The surface of Pluto as it is understood on the eve of the encounter of the New Horizons spacecraft (mid-2015) consists of a spatially heterogeneous mix of solid N2, CH4, CO, C2H6, and an additional component that imparts color, and may not be an ice. The known molecular ices are detected by near-infrared spectroscopy. The N2 ice occurs in the hexagonal crystalline b-phase, stable at T > 35.6 K...
متن کاملThe New Horizons Radio Science Experiment
The New Horizons (NH) Radio Science Experiment, REX, is designed to determine conditions on Pluto as manifest in the atmospheric state at the surface and a few scale heights higher. Expected absolute accuracies in n, p, and T at the surface are 4·10 m−3, 0.1 Pa, and 3 K, respectively, obtained by radio occultation of a 4.2 cm-λ signal transmitted from Earth at 10–30 kW and received at the NH sp...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Science
دوره 351 6279 شماره
صفحات -
تاریخ انتشار 2016