China releases first Tianwen-1 images of rover landing site
The new colonial movement: China yesterday released the first two images taken by its Mars orbiter Tianwen-1 of its planned rover landing site in the northern lowland plains of Mars.
The image to the right is a mosaic of two wide angle photos from the context camera on Mars Reconnaissance Orbiter (MRO). The white cross is the spot of the latitude and longitude that had previously been leaked to the Chinese press as the landing site. The white box shows the area covered by the only high resolution MRO photo, as of October 2020. Since then MRO has taken a number of additional high resolution images of this area.
The red boxes mark the areas covered by Tianwen-1’s two new images. Below is a reduced version of the larger of these two photos.
Click for full image.
These two images confirm that this location was the rover’s prime landing site. However, the release of the images also included the announcement that they have pushed back the rover landing from late April to May or even June. Either they have decided it is going to take more time to cover this area with reconnaissance photos, or these first photos have forced them to reconsider the landing site.
That these two photos keyed in on the two largest features in this area suggests they are assessing the landing site. We do not know how much smooth territory the lander needs to settle down between these large features. Nor do we know the exact technology the lander will use to maneuver its way down. It could be it will use these images as reference, which means they must collect enough images to cover the entire area before landing.
Or it could be these images have told them this location won’t work and thus the delay in landing.
I think the answer is the former. However, we will have to wait to find out. China’s government is not going to be forthcoming with many details.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon. from any other book seller, or direct from my ebook publisher, ebookit.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
The new colonial movement: China yesterday released the first two images taken by its Mars orbiter Tianwen-1 of its planned rover landing site in the northern lowland plains of Mars.
The image to the right is a mosaic of two wide angle photos from the context camera on Mars Reconnaissance Orbiter (MRO). The white cross is the spot of the latitude and longitude that had previously been leaked to the Chinese press as the landing site. The white box shows the area covered by the only high resolution MRO photo, as of October 2020. Since then MRO has taken a number of additional high resolution images of this area.
The red boxes mark the areas covered by Tianwen-1’s two new images. Below is a reduced version of the larger of these two photos.
Click for full image.
These two images confirm that this location was the rover’s prime landing site. However, the release of the images also included the announcement that they have pushed back the rover landing from late April to May or even June. Either they have decided it is going to take more time to cover this area with reconnaissance photos, or these first photos have forced them to reconsider the landing site.
That these two photos keyed in on the two largest features in this area suggests they are assessing the landing site. We do not know how much smooth territory the lander needs to settle down between these large features. Nor do we know the exact technology the lander will use to maneuver its way down. It could be it will use these images as reference, which means they must collect enough images to cover the entire area before landing.
Or it could be these images have told them this location won’t work and thus the delay in landing.
I think the answer is the former. However, we will have to wait to find out. China’s government is not going to be forthcoming with many details.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon. from any other book seller, or direct from my ebook publisher, ebookit. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
IF, it actually hits the planet and does not RUD, it will likely “see” a scene very much like what Sojourner, Spirit and Opportunity, Curiosity, and Perseverance have observed over the past decades.
With respect to the entry, descent, and landing technology the Chinese might use, I see three basic options:
1. Skycrane
2. Airbag
3. Retrorockets
I think it must be Airbag, since it is the simplest choice and they have Spirit and Opportunity to copy.
Retrorockets leave you carrying your landing equipment around on a solar-powered rover, reducing ground performance significantly, thus they have been used only on stationary landers.
Skycrane seems risky for a highly-politically-visible first effort.
Other options, or conclusions?
Ray Van Dune: I think they will be using a combination of retrorockets and airbags. See this post from November 2019: China unveils Mars lander during landing simulation test
The test showed rockets being used to control the landing. I have read elsewhere that airbags will also be involved.
Bob, I do not understand what I am seeing in that Chinese video, but it looks like a nightmare rig! But I was wrong in saying retros were only used on landers not rovers. I was thinking only of on-vehicle retros, but I forgot about the retro packs used below the parachutes by Spirit and Opportunity, and fired at the last moment to cushion the landing of the airbag “ball”. I’ll bet the Chinese use that retro-airbag combo.