nivek
As Above So Below
Mars' Eberswalde crater delta – in 3D
(Download the image on the link)
This intricate structure of an ancient river delta once carried liquid water across the surface of Mars.
To best enjoy this image, produced with infrared and visible filters on the Colour and Stereo Surface Imaging System (CaSSIS) of the ESA-Roscosmos ExoMars Trace Gas Orbiter, view through red/green ‘3D’ glasses.
To create a stereo view like this, the orbiter’s camera uses a motor to rotate its telescope and take photos from different angles. The two views can be put together to make a three-dimensional view. Click here to see one of the pair of images that comprise the ‘stereo pair’.
The distinctive form of a delta arises from sediments that are deposited by a river as it enters slower-moving water, like a lake or a sea, for example. The Nile River delta is a classic example on Earth, and uncannily similar features have been spotted on Saturn’s moon Titan and – closer to home – Mars. While liquid water is no longer present on the surface of Mars, features in the left portion of this image provide strong evidence of it having played an important role in the history of the Red Planet. Furthermore, water-ice is still stable on the surface today, and a recent discovery from Mars Express detected a pocket of liquid water below the surface.
The 100-metre-thick fan-shaped deposit seen in this image is found in Eberswalde crater in the southern hemisphere of Mars (326.33ºE/23.55ºS). The image covers an area of 31 x 7.5 km and was taken on 16 November 2018.
While presented in beautiful aqueous blues and greens, the image is false-colour. The layered rocks that comprise the delta deposits are indicated in white/yellow to purple/blue. The yellow represents the presence of oxidised iron deposits, indicating that the rocks were altered by the presence of water, while the blues signify less altered materials. This suggests that the influence of liquid water reduced over time, perhaps relating to a change in environmental conditions.
After the deposition of the delta sediments in the crater’s ancient lake, fresher sediments – some perhaps deposited by wind – accumulated to cover up a major part of the delta and its connecting channels. These secondary sediments were later eroded in the delta, exposing an inverted relief of the structure that is observed today.
.
(Download the image on the link)
This intricate structure of an ancient river delta once carried liquid water across the surface of Mars.
To best enjoy this image, produced with infrared and visible filters on the Colour and Stereo Surface Imaging System (CaSSIS) of the ESA-Roscosmos ExoMars Trace Gas Orbiter, view through red/green ‘3D’ glasses.
To create a stereo view like this, the orbiter’s camera uses a motor to rotate its telescope and take photos from different angles. The two views can be put together to make a three-dimensional view. Click here to see one of the pair of images that comprise the ‘stereo pair’.
The distinctive form of a delta arises from sediments that are deposited by a river as it enters slower-moving water, like a lake or a sea, for example. The Nile River delta is a classic example on Earth, and uncannily similar features have been spotted on Saturn’s moon Titan and – closer to home – Mars. While liquid water is no longer present on the surface of Mars, features in the left portion of this image provide strong evidence of it having played an important role in the history of the Red Planet. Furthermore, water-ice is still stable on the surface today, and a recent discovery from Mars Express detected a pocket of liquid water below the surface.
The 100-metre-thick fan-shaped deposit seen in this image is found in Eberswalde crater in the southern hemisphere of Mars (326.33ºE/23.55ºS). The image covers an area of 31 x 7.5 km and was taken on 16 November 2018.
While presented in beautiful aqueous blues and greens, the image is false-colour. The layered rocks that comprise the delta deposits are indicated in white/yellow to purple/blue. The yellow represents the presence of oxidised iron deposits, indicating that the rocks were altered by the presence of water, while the blues signify less altered materials. This suggests that the influence of liquid water reduced over time, perhaps relating to a change in environmental conditions.
After the deposition of the delta sediments in the crater’s ancient lake, fresher sediments – some perhaps deposited by wind – accumulated to cover up a major part of the delta and its connecting channels. These secondary sediments were later eroded in the delta, exposing an inverted relief of the structure that is observed today.
.