Hubble Space Telescope Neptune

The Hubble Space Telescope observed Neptune in 1994 from Earth orbit and detected cloud features in its atmosphere which appeared to be different from those observed by Voyager 2 in 1989. The main change no-... 

Researchers have learned a vast amount of new information about Jupiter, Saturn, Uranus, Neptune, Pluto and the Kuiper Belt Objects in the last century. Improved terrestrial telescopes, the Hubble Space Telescope, and space explorations such as Voyager 1 and 2, Galileo, and Cassini have produced new data that will take astrochemists years to analyze and interpret, providing them with even more detailed information about the chemical composition of the atmospheres, satellites, surfaces, and other features of the outer planets and their associated bodies. 

Atmospheres of extraterrestrial planets can be directly studied during a transit. Two transit events with the Near Infrared Camera and Multi Object Spectrograph (NIC-MOS) camera on the Hubble Space Telescope (HST) were observed for the object GJ 436 b. In order to detect the atmosphere, high-cadence time series of prism spectra covering the 1.1-1.9 pm spectral range were analyzed (Pont et al., 2009 [266]). This object is an extrasolar hot Neptune. The authors measured a flat transmission spectrum at the level of a few parts per 10000 in flux, with no significant signal in the 1.4 pm water band. 

Pont, F., Gilliland, R.L., Knutson, H., Holman, M., Charbonneau, D. Transit infrared spectroscopy of the hot Neptune around GJ 436 with the Hubble Space Telescope. Mon. Not. 393,6-10 (2009)... 

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