A familiar ingredient has been on the
Surface of Jupiter's moon Europe. Using a visible light spectral analysis
Planetary scientists at Caltech and NASA's Jet Propulsion Laboratory in
Pasadena, California, has discovered that the yellow color is visible on parts
From the surface of Europe comes sodium chloride, a compound known on earth
as table salt, which is also the main constituent of sea salt.
The discovery suggests that the salty ocean floor of
Europe could be more chemically similar to Earth's oceans than previously thought.
for decades to question conjectures about the composition of these waters. The
Findings were published by Science
Progress on June 1
Flybys from NASA Voyager
and Galileo spaceship have guided
The scientists conclude that Europe is covered by a layer of salty liquid water
Wrapped in an icy shell. Galileo carried an infrared spectrometer
With these instruments, scientists are studying the composition of a surface they are studying.
Galileo's spectrometer found water ice and a substance that appeared to be
Magnesium sulfate salts (such as bittersalts). There the icy shell is geological
it was young and has abundant evidence of past geological activity
assumes that all salts present on the surface can originate from the ocean
"People have traditionally believed that all
Interesting spectroscopy takes place in the infrared on planetary surfaces, because
There, most of the molecules that scientists are looking for have theirs
basic features, "said Mike Brown, the Richard and Barbara Rosenberg
Professor of planetary astronomy at Caltech and co-author of science
Progress in paper form.
"No one has recorded spectra of visible wavelength Europe
previously had this kind of spatial and spectral resolution. The Galileo spaceship had none
visible spectrometer. It had only one near-infrared spectrometer and near-infrared,
Chlorides are without characteristics, "said Caltech student Samantha Trumbo.
Main author of the work.
This changed as new data with higher spectral resolution appeared
proposed by the W. M. Keck Observatory on the dormant volcano Maunakea in Hawaii
that the scientists actually saw no magnesium sulphates on Europe. Most
The sulfate salts considered above have pronounced absorptions, the
serve as fingerprints for connections that should have been visible on the Internet
higher quality Keck data. However, it is expected that the spectra reflect the regions
the internal composition lacked one of the characteristic sulfate absorptions.
"We thought we could see sodium chlorides
in the infrared spectrum, however, they are essentially imperceptible, "said Brown.
In the meantime, JPL scientist Kevin Hand had used the ocean sample
Salts that have been bombarded with radiation in a laboratory under Europe-like conditions, and
found out that several new and different features have arisen in sodium chloride
Irradiation. He discovered that they changed the colors to the point where they were
could be identified with an analysis of the visible spectrum. Sodium chloride,
For example, a yellow hue became similar to that in a geologically visible one
young area of Europe known as "Tara Regio".
"Sodium chloride is a bit of invisible ink on Europe's
Surface. You can not say that it is there before the irradiation, but after the irradiation
The paint jumps right on you, "said Hand.
Taking a closer look at NASA's NASA / ESA Hubble Space
With the telescope, the research team was able to achieve a significant absorption in the
visible spectrum at 450 nanometers corresponding to the irradiated salt
exactly what confirms that the yellow color of Tara Regio mirrored that
Presence of irradiated sodium chloride on the surface.
"We had the ability to do this analysis with the
Hubble Space Telescope for 20 years, "Brown said. It's easy
that nobody thought to look.
While the findings do not guarantee that this sodium
Chloride comes from the subterranean ocean (this could indeed be easy)
Evidence of different types of materials layered in the ice shell of the moon),
The authors of the study suggest that a re-evaluation of geochemistry is needed
"Magnesium sulfate would simply be leached into the deposit
Ocean from the rocks on the seabed, but sodium chloride can indicate the ocean
Soil is hydrothermally active, "said Trumbo. That would mean Europe
is a geologically interesting planetary body than before
The study is titled "Sodium chloride on the surface of Europe". These
The research was supported by the NASA Earth and Space Science Fellowship Program.
the Space Telescope Science Institute and JPL, which is managed by Caltech for
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