IPB

Welcome Guest ( Log In | Register )

2 Pages V  < 1 2  
Reply to this topicStart new topic
Venus surface images
Hungry4info
post Mar 17 2021, 11:35 PM
Post #16


Senior Member
****

Group: Members
Posts: 1241
Joined: 26-July 08
Member No.: 4270



And here's the same from Venera 14 Camera 1, taking the three usable frames for this. It looks like there was a dramatic removal of dust between two of the frames that also perturbed the... debris thing(?) near the centre of the frame. There is only one usable frame from the Venera 14 Camera 2, so I will not attempt it on the other side. It doesn't look like any dust was kicked up anyway, being the famous "smooth slab" image.

Has this been noticed before? I did some googl'ing around and found Garvin 1981 and Greeley & Arvidson (1990) which talk about dust kicked up by the landers, but I didn't read anything on visual confirmation of dust being moved by wind.
Attached thumbnail(s)
Attached Image
 


--------------------
-- Hungry4info (Sirius_Alpha)
Go to the top of the page
 
+Quote Post
rlorenz
post Mar 18 2021, 01:53 AM
Post #17


Member
***

Group: Members
Posts: 540
Joined: 23-February 07
From: Occasionally in Columbia, MD
Member No.: 1764



QUOTE (Hungry4info @ Mar 17 2021, 06:35 PM) *
It looks like there was a dramatic removal of dust between two of the frames....
Has this been noticed before? I did some googl'ing .....I didn't read anything on visual confirmation of dust being moved by wind.


Of course it was noticed. But it is indeed perhaps not well known, and is quite remarkable, you would typically have to wait weeks or months to see such a change on Earth

As my review of Venus surface wind measurements notes "The probabilistic framework articulated in this paper supports
this contention of vigorous surface transport. Surface panoramas (e.g. Garvin et al., 1984) from the Venera landers show fine material
to be widely present. Of the 6 landers equipped with cameras, four returned images (the lens caps on Venera 11, 12 failed to
eject). Of these, only Venera 13 and 14 provided multiple panoramas which allowed change detection. Changes in the distribution
of surface particulates on the lander ring are seen in Venera 13 images (e.g. Selivanov et al., 1982; see also discussion in
Ksanfomality et al., 1983). Thus, out of only two occasions in which surface particle transport could possibly have been observed, it was
observed in one (with only about an hour between observations). Movement of surface particulates by wind has been observed on
many occasions on Mars, indeed (e.g. Lorenz and Zimbelman, 2014), but only after years of landed spacecraft operations (e.g.
Arvidson et al., 1983; Sullivan et al., 2005) and high-resolution orbital observations (e.g. Bridges et al., 2012).

The paper by the original imaging investigator is
Selivanov, A.S. et al., 1982. Evolution of the Venera 13 imagery. Sov. Astron. Lett. 8, 433436.
Go to the top of the page
 
+Quote Post
Marcin600
post Mar 19 2021, 07:33 PM
Post #18


Member
***

Group: Members
Posts: 319
Joined: 14-December 15
Member No.: 7860



QUOTE (Hungry4info @ Mar 18 2021, 12:35 AM) *
...It looks like there was a dramatic removal of dust between two of the frames that also perturbed the... debris thing(?) near the centre of the frame...

Outstanding, Hungry4info!
This is the first time I can see any movement on the surface of Venus!
Really amazing - after so many years you can still discover something new in such old photos.

The gusts of wind had to be strong enough to blow away the dust/sand that was lying on the lander's aerodynamic ring (sand/dust that fell on the ring when the probe landed).


PS Do you have the option to use slightly larger pictures for these animations?

And what exactly is this "debris thing(?) near the centre of the frame" ? Damaged camera cover?
Go to the top of the page
 
+Quote Post
Hungry4info
post Mar 20 2021, 01:17 AM
Post #19


Senior Member
****

Group: Members
Posts: 1241
Joined: 26-July 08
Member No.: 4270



QUOTE
PS Do you have the option to use slightly larger pictures for these animations?

I'm afraid not. Those are the highest-resolution images I have. I'm definitely interested in knowing if anyone else has larger raws though.


--------------------
-- Hungry4info (Sirius_Alpha)
Go to the top of the page
 
+Quote Post

2 Pages V  < 1 2
Reply to this topicStart new topic

 



RSS Lo-Fi Version Time is now: 18th April 2021 - 11:12 AM
RULES AND GUIDELINES
Please read the Forum Rules and Guidelines before posting.

IMAGE COPYRIGHT
Images posted on UnmannedSpaceflight.com may be copyrighted. Do not reproduce without permission. Read here for further information on space images and copyright.

OPINIONS AND MODERATION
Opinions expressed on UnmannedSpaceflight.com are those of the individual posters and do not necessarily reflect the opinions of UnmannedSpaceflight.com or The Planetary Society. The all-volunteer UnmannedSpaceflight.com moderation team is wholly independent of The Planetary Society. The Planetary Society has no influence over decisions made by the UnmannedSpaceflight.com moderators.
SUPPORT THE FORUM
Unmannedspaceflight.com is a project of the Planetary Society and is funded by donations from visitors and members. Help keep this forum up and running by contributing here.