Astronomy Picture of the Day
March 1, 2015

Caloris Basin
Caloris Basin

Credits: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington and Dr Paolo C. Fienga/LXTT/IPF for the additional process. and color.

In this really fascinating and highly suggestive image-mosiac, obtained by putting together several pictures taken by the NASA - MESSENGER Spacecraft at different Sun Angles (such as during different orbits around Mercury and therefore at different Mercurian Local Time), we can see the huhe and magnificent Mercurian Impact Feature known as Caloris Basin (which is approximately 1525 Km - such as about 947,025 miles - across).

Caloris Basin has been flooded, eons ago, by large (actually, enormous) amounts of Lava that appear brown-orange colored in this mosaic. Afterwards, post-flooding Impact Craters have excavated (---> unearthed) Material from beneath the Surface. The larger of these Impact Craters have exposed - we would say, as IPF, "just as usual" - some Low-Reflectance Material ( or "LRM", for short, that appears VERY dark, or even black here) from beneath the Surface Lavas, likely giving us a glimpse of the original Basin Floor Material.

The analysis which have been already carried out about these Impact Craters yields an estimate of the thickness (---> depth) of the Volcanic Lava Layer that goes (!) from about 2,5 up to approx. 3,5 Km (such as from about 1,5525 up to approx. 2,173 miles).

InstrumentMercury Dual Imaging System (MDIS)
Center Latitude: 31,50° North
Center Longitude: 162,70° East
Solar Incidence Angle (at center frame): 82,4° (meaning that the Sun, at the time that the pictures were taken, was about 7,6° above the imaged Local Mercurian Horizon)
Emission Angle (at center frame): 0,1° (meaning that the Spacecraft was almost perpendicular as to the imaged Surface at the time when the picture was taken)
Sun-Mercury-Messenger (or "Phase") Angle (at center frame): 82,5°

This picture (which is an Original NASA - MESSENGER Spacecraft's falsely colored and Ortographically Map-Projected image-mosaic published on the NASA - Planetary Photojournal with the ID n. PIA 19216) has been additionally processed, contrast enhanced, Gamma corrected, magnified to aid the visibility of the details and then colorized in Absolute Natural Colors (such as the colors that a human eye would actually perceive if someone were onboard the NASA - MESSENGER Spacecraft and then looked outside, towards the Surface of Mercury), by using an original technique created - and, in time, dramatically improved - by the Lunar Explorer Italia Team. Different colors, as well as different shades of the same color, mean, among other things, the existence of different Elements (Minerals) present on the Surface of Mercury, each having a different Albedo (---> Reflectivity) and Chemical Composition.

News visualized: 637 times

©2011-2023 - Powered by - All rights reserved