Neptune surface temperature
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Surface Temperature of Neptune: An Overview
Introduction to Neptune's Atmospheric Temperature
Neptune, the eighth planet from the Sun, exhibits a complex and dynamic atmosphere with varying temperatures across different layers. Understanding the surface temperature of Neptune involves analyzing data from various missions and observations, including those from the Voyager 2 spacecraft and ground-based telescopes.
Infrared Observations and Temperature Mapping
Infrared observations from the Voyager 2 mission have provided significant insights into Neptune's atmospheric temperatures. The thermal emission spectra obtained by the infrared interferometer spectrometer on Voyager 2 revealed that the effective temperature of Neptune is approximately 59.3 ± 1.0 kelvins1. This data was further supported by temperature maps derived from measurements between 80°S and 30°N, indicating a relatively warm pole and equator with cooler mid-latitudes1.
Upper Atmosphere Temperature
The upper atmosphere of Neptune, primarily composed of atomic and molecular hydrogen, has been studied through ultraviolet spectrometer observations. These observations suggest that the temperature in the upper levels of Neptune's atmosphere is around 750 ± 150 kelvins2. This high temperature is indicative of the complex thermal dynamics and energy distribution in Neptune's upper atmosphere.
Stratospheric Temperature
Further analysis of Neptune's stratosphere using thermal spectroscopy has shown that the temperature near the 1-10 μbar pressure level is approximately 168 K, with an uncertainty of ±10 K3. This temperature profile is consistent with various spectral features observed in the infrared range, providing a detailed understanding of the stratospheric conditions on Neptune.
Tropopause and Lower Atmosphere
The tropopause, a critical boundary layer in Neptune's atmosphere, is located about 40 km above the 1-bar pressure level, where the temperature is around 52 ± 2 K4. This region marks the transition between the troposphere and the stratosphere and plays a crucial role in the atmospheric dynamics of Neptune.
Conclusion
In summary, the surface temperature of Neptune varies significantly across different atmospheric layers. The effective temperature of the planet is around 59.3 K, with the upper atmosphere reaching temperatures as high as 750 K. The stratosphere and tropopause exhibit temperatures of approximately 168 K and 52 K, respectively. These findings highlight the complex and dynamic nature of Neptune's atmosphere, driven by various thermal and chemical processes.
Sources and full results
Most relevant research papers on this topic
Infrared Observations of the Neptunian System
Neptune has a warm pole and equator with cooler mid-latitudes, similar to Uranus, and strong longitudinal thermal structure.
Highly CitedUltraviolet Spectrometer Observations of Neptune and Triton
Neptune's upper atmosphere is mostly hydrogen, with methane, acetylene, and ethane at lower levels, and Triton's atmosphere mainly consists of molecular nitrogen with traces of methane near the surface.
Highly CitedThermal spectroscopy of Neptune: the stratospheric temperature, hydrocarbon abundances, and isotopic ratios
Neptune's stratospheric temperature is 168 K near 1-10 bar pressure, with an uncertainty of 10 K, and its hydrocarbon abundances are consistent with previous measurements.
The atmosphere of Neptune : an analysis of radio occultation data acquired with Voyager 2
Neptune's atmosphere consists of 78-84 percent hydrogen at the tropopause, with a temperature of 52 +/-2 K, and the 1-bar isobaric surface has a temperature of 72 +/-2 K.
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