Post by Andrei Tchentchik on Jun 26, 2019 18:31:10 GMT 2
(.#226).- Surprised, the asteroid Ultima Thule is flat like a pancake.
Surprised, the asteroid Ultima Thule is flat like a pancake.
By Tristan Vey - Updated on 12/02/2019 at 08:51
The images taken as the probe passed behind the asteroid before continuing its course towards the confines of the solar system made it possible to take the measure of its strange shape, very flattened. NASA / Johns Hopkins University Applied Physics Laboratory / Southwest Research Institute.
The most distant object visited by man, far beyond Pluto, is revealed little by little as the images of the overflight made in the night of January 31 reach us.
No more snowman. Teams from NASA's New Horizons probe are now talking about a large pancake-shaped lobe (Ultima) and a small, dented nut (Thule). This is perhaps the greatest surprise reserved by Ultima Thule, the most distant asteroid ever visited by man. Not only is it a binary body composed of two parts in contact (as well as comet 67P visited by Rosetta) but it is mostly flattened like a pancake.
The images of the overflight made in the night of last December 31 arrive dropper (it will take another year and a half to collect all the data collected in a few hours). A series of 14 shots unveiled last Friday shows the last moments of the flyover, when the probe passes behind the asteroid to continue its route to the confines of the Solar System. The asteroid then has only a thin surface illuminated by the Sun.
It is not easy to see on these images the shape of the object ... But if we look carefully at the images, we can see that the dark part of the asteroid hides the stars in the background which allows us to estimate its thickness at different points, as it advances in front of this background. By cross-checking this information with that of the approach (which already had a glimpse of at least a slightly flattened form), the engineers managed to create a 3D model that reveals its strange and unexpected shape :
VIDÉO YOUTUBE :
Duration : 0m12s
"We had a first representation of Ultima Thule based on a limited number of images that had arrived in the days following the flyby, but discovering these new images has significantly changed our vision," says Alan Stern, chief scientist of mission to the Southwest Research Institute. "It would be more appropriate to say that the form of Ultima Thule is flattened like a pancake (rather than comparing it to a snowman, Ed). But what is more important is that these new images pose a real scientific puzzle about how such an object could be formed. We have never seen anything like that in orbit around the Sun. "
Ultima Thule had kept its secret for two reasons: the probe New Horizons arrived in front of this object and its axis of rotation pointed towards the probe. This constitutes a rather surprising double coincidence. "This will undoubtedly require new theories about the formation of planetesimals in the Early Solar System," says Hal Weaver, the project's scientific lead at the Johns Hopkins Applied Physics Laboratory.
The clearest images of this overview released to date (late January) also raised other questions. The presence of many "wells" or "craters" surprised the scientists. Ultima Thule is located in a very cold and depopulated area of the Solar System where collisions are (in principle) rare and where the low brightness of the Sun should not be able to alter so much its surface.
F I N .
Surprised, the asteroid Ultima Thule is flat like a pancake.
By Tristan Vey - Updated on 12/02/2019 at 08:51
The images taken as the probe passed behind the asteroid before continuing its course towards the confines of the solar system made it possible to take the measure of its strange shape, very flattened. NASA / Johns Hopkins University Applied Physics Laboratory / Southwest Research Institute.
The most distant object visited by man, far beyond Pluto, is revealed little by little as the images of the overflight made in the night of January 31 reach us.
No more snowman. Teams from NASA's New Horizons probe are now talking about a large pancake-shaped lobe (Ultima) and a small, dented nut (Thule). This is perhaps the greatest surprise reserved by Ultima Thule, the most distant asteroid ever visited by man. Not only is it a binary body composed of two parts in contact (as well as comet 67P visited by Rosetta) but it is mostly flattened like a pancake.
The images of the overflight made in the night of last December 31 arrive dropper (it will take another year and a half to collect all the data collected in a few hours). A series of 14 shots unveiled last Friday shows the last moments of the flyover, when the probe passes behind the asteroid to continue its route to the confines of the Solar System. The asteroid then has only a thin surface illuminated by the Sun.
It is not easy to see on these images the shape of the object ... But if we look carefully at the images, we can see that the dark part of the asteroid hides the stars in the background which allows us to estimate its thickness at different points, as it advances in front of this background. By cross-checking this information with that of the approach (which already had a glimpse of at least a slightly flattened form), the engineers managed to create a 3D model that reveals its strange and unexpected shape :
VIDÉO YOUTUBE :
Duration : 0m12s
"We had a first representation of Ultima Thule based on a limited number of images that had arrived in the days following the flyby, but discovering these new images has significantly changed our vision," says Alan Stern, chief scientist of mission to the Southwest Research Institute. "It would be more appropriate to say that the form of Ultima Thule is flattened like a pancake (rather than comparing it to a snowman, Ed). But what is more important is that these new images pose a real scientific puzzle about how such an object could be formed. We have never seen anything like that in orbit around the Sun. "
Ultima Thule had kept its secret for two reasons: the probe New Horizons arrived in front of this object and its axis of rotation pointed towards the probe. This constitutes a rather surprising double coincidence. "This will undoubtedly require new theories about the formation of planetesimals in the Early Solar System," says Hal Weaver, the project's scientific lead at the Johns Hopkins Applied Physics Laboratory.
The clearest images of this overview released to date (late January) also raised other questions. The presence of many "wells" or "craters" surprised the scientists. Ultima Thule is located in a very cold and depopulated area of the Solar System where collisions are (in principle) rare and where the low brightness of the Sun should not be able to alter so much its surface.
F I N .
