Mars rovers provide another perspective on farside solar activity

[Philalethes]

1 hour ago, arjemma said:

I am not a camera expert either but I know a thing or two about photo editing. If there were dead pixels then those pixels would be dead on all photos taken with the same camera during the same time span. I have downloaded some images and have compared them on pixel level. Those pixels aren't dead on all photos and therefore it's not logical that they somehow are only dead on the photos of the sun. From what I have seen when I have compared the photos I would say that those are stars. I can't tell for sure though and I'm not 100%. This is just my evaluation on the raw photos that are available.

EDIT!
I have now found the pixel on three other photos so maybe they are artifacts after all? Very hard to tell.

Yeah, it had me fooled very thoroughly at first, to the point where I was quite certain they were stars; it's definitely not easy to tell at all. At this point I agree that they're clearly artifacts, and there are probably different factors determining why they're only present in some, such as e.g. only being found in photos taken of Sol directly and probably different for each camera. The conclusion was that it seems to be hot pixels like Sam was saying and that they somehow get smeared out due to the filter; you can of course read what we went through and judge for yourself, but something like that seems most likely.

[arjemma]

5 minutes ago, Philalethes said:

Yeah, it had me fooled very thoroughly at first, to the point where I was quite certain they were stars; it's definitely not easy to tell at all. At this point I agree that they're clearly artifacts, and there are probably different factors determining why they're only present in some, such as e.g. only being found in photos taken of Sol directly and probably different for each camera. The conclusion was that it seems to be hot pixels like Sam was saying and that they somehow get smeared out due to the filter; you can of course read what we went through and judge for yourself, but something like that seems most likely.

Same here, I was pretty convinced until I found it on a few other photos. They are very subtle on the photos that aren't of the black space. I have read it all after I responded and I think you all came to a reasonable conclusion.

I have read the links posted in this thread and this is very interesting indeed. I haven't even thought of that the Perseverance rover take photos of the sun occasionally so this is very cool! I wonder if Nasa have a way to tell where the sunspots are located from the photos?

This for sure could be a good tool for confirming farside predictions and therefore get better models for it. It's sucks that STEREO B is dead and that A is right at earth nowadays.

[Philalethes]

2 minutes ago, arjemma said:

I wonder if Nasa have a way to tell where the sunspots are located from the photos?

Exactly what we were wondering too! That's pretty much what I was trying to determine, which I failed completely at, and given what I know now I can't think of any solution that doesn't involve photos at times spaced far enough apart for the rotation to be evident, e.g. a day apart. I also figured that maybe NASA has a way of determining it from the exact location and orientation of the rover and camera, so I sent them an email about it, but no response so far. I would suspect that they haven't really put any effort into that at this point, but maybe if prodded someone there will and perhaps provide space weather enthusiasts with the orientation too.

8 minutes ago, arjemma said:

This for sure could be a good tool for confirming farside predictions and therefore get better models for it. It's sucks that STEREO B is dead and that A is right at earth nowadays.

Yep. Something like ESA's planned Vigil mission but for L3 would be great, but for a number of reasons I think that's probably not going to happen anytime soon. Having Vigil at L5 will be a great improvement though, but sadly the launch isn't planned until the end of the decade, at which point SC25 will presumably be nearing its end; will be great to have for SC26 and however many future cycles it will endure through though.

[arjemma]

8 minutes ago, Philalethes said:

Exactly what we were wondering too! That's pretty much what I was trying to determine, which I failed completely at, and given what I know now I can't think of any solution that doesn't involve photos at times spaced far enough apart for the rotation to be evident, e.g. a day apart. I also figured that maybe NASA has a way of determining it from the exact location and orientation of the rover and camera, so I sent them an email about it, but no response so far. I would suspect that they haven't really put any effort into that at this point, but maybe if prodded someone there will and perhaps provide space weather enthusiasts with the orientation too.

Yep. Something like ESA's planned Vigil mission but for L3 would be great, but for a number of reasons I think that's probably not going to happen anytime soon. Having Vigil at L5 will be a great improvement though, but sadly the launch isn't planned until the end of the decade, at which point SC25 will presumably be nearing its end; will be great to have for SC26 and however many future cycles it will endure through though.

Oh yea right, I read that you sent an email, sorry I forgot. I hope that they take their time and answer you cause that is a really good question. If they have a way to know it could make space weather prediction slightly easier. Makes sense for NASA to know the location of their rover (I really hope they do know) so it should be plausible for them to determine where the sun is in its rotation compared to earth. Also if they do know this, they should post it on the swpc site and have it under products or something similar. Sure they would have to put down time and money to do it but I think it would be interesting for a lot of people in the space weather community. If you don't get an answer to your email within reasonable time, maybe more members here can email so they see that there are people interested in it.

Yes, unfortunately it's probably not at the top of their priorities. Vigil will be very interesting and I can't wait for it to be up and running. A while ago I heard that they would launch it in 2025 so I will be sad if they wait longer. I hope they up their game for SC26 and let us have a few more satellites to play with. I can't wait for GOES-U and Vigil.

[Newbie]

A point of interest relating to the latest pic from the Perseverance rover is the proximity to the limb of the incoming active regions. It gives a good indication of how the views from the Mars mast-cams compare with our view of the sun.

I was able to do a rough estimate of how much rotation was required so that the  Mars pic was aligned with the far-side image grid.

Apologies for Low Res.

View from Mars rover.
Rotated image is on the right.

Comparison of rotated Mars pic and far-side image.
N.

Edited November 2, 2023 by Newbie

[tniickck]

were there any photos from Mars of 2 big incoming regions on the farside? 

[Newbie]

5 hours ago, tniickck said:

were there any photos from Mars of 2 big incoming regions on the farside? 

Due to Mars passing directly behind the sun, the rovers and helicopter have been turned off and parked. This is the case between 11th and 25th November.
The loss of radio transmissions passing through the Suns atmosphere causes the craft to do strange things so it was deemed sensible to deactivate them.

So no, no imagery is available currently.

N.

Edited November 18, 2023 by Newbie

[Sapphire828]

Mars solar conjunction is over and we've been receiving pictures again since about early December.
The last solar image was taken on Sol 1009 ~12/22/23 and shows a huge sunspot.

Courtesy of spaceweather.com on 12/26/23:

@Philalethes Did you ever hear back from NASA about the orientation of these pictures and a way to approximate the rotation time?

 

 

Here's my estimation based on the latest image from Mars:

Mars_Perseverance_ZL7_1009_0756515107_707EBY_N0482404ZCAM01081_1100LMJ.png
Sol 1009, Left Mastcam-Z, This image was acquired on Dec. 22, 2023 (Sol 1009) at the local mean solar time of 12:49:38.

I'll make a rough assumption the sun's equator is vertical in the picture and take the lengths of the red lines.

Full length red line 5.06 units
Shorter red line with the middle sunspot position 3.06 units
Ratio~0.605

Carrington rotation ~27.3 days, half Carrington rotation ~13.65 days
13.65 days*0.605 = 8.25 days from 12/22/23 noon

Dec22.5+8.25=30.75, rounded 31

ETA at East limb ~12/31/23

[hamateur 1953]

Well done! And we should have corroborated evidence soon hopefully if they can hang on a bit longer.  

[tniickck]

1 hour ago, Sapphire828 said:

Mars solar conjunction is over and we've been receiving pictures again since about early December.
The last solar image was taken on Sol 1009 ~12/22/23 and shows a huge sunspot.

Courtesy of spaceweather.com on 12/26/23:

@Philalethes Did you ever hear back from NASA about the orientation of these pictures and a way to approximate the rotation time?

 

 

Here's my estimation based on the latest image from Mars:

Mars_Perseverance_ZL7_1009_0756515107_707EBY_N0482404ZCAM01081_1100LMJ.png
Sol 1009, Left Mastcam-Z, This image was acquired on Dec. 22, 2023 (Sol 1009) at the local mean solar time of 12:49:38.

I'll make a rough assumption the sun's equator is vertical in the picture and take the lengths of the red lines.

Full length red line 5.06 units
Shorter red line with the middle sunspot position 3.06 units
Ratio~0.605

Carrington rotation ~27.3 days, half Carrington rotation ~13.65 days
13.65 days*0.605 = 8.25 days from 12/22/23 noon

Dec22.5+8.25=30.75, rounded 31

ETA at East limb ~12/31/23

Very nice! yall always provide us with some Mars photos. 

this must be 3514 

 

Edited December 26, 2023 by tniickck

[Misaka]

2 hours ago, Sapphire828 said:

Mars solar conjunction is over and we've been receiving pictures again since about early December.
The last solar image was taken on Sol 1009 ~12/22/23 and shows a huge sunspot.

Courtesy of spaceweather.com on 12/26/23:

@Philalethes Did you ever hear back from NASA about the orientation of these pictures and a way to approximate the rotation time?

 

 

Here's my estimation based on the latest image from Mars:

Mars_Perseverance_ZL7_1009_0756515107_707EBY_N0482404ZCAM01081_1100LMJ.png
Sol 1009, Left Mastcam-Z, This image was acquired on Dec. 22, 2023 (Sol 1009) at the local mean solar time of 12:49:38.

I'll make a rough assumption the sun's equator is vertical in the picture and take the lengths of the red lines.

Full length red line 5.06 units
Shorter red line with the middle sunspot position 3.06 units
Ratio~0.605

Carrington rotation ~27.3 days, half Carrington rotation ~13.65 days
13.65 days*0.605 = 8.25 days from 12/22/23 noon

Dec22.5+8.25=30.75, rounded 31

ETA at East limb ~12/31/23

Looks like you are correct with the date. SDO also predicts it on the 31.12.2023

http://jsoc.stanford.edu/data/farside/

[tniickck]

1 hour ago, Misaka said:

Looks like you are correct with the date. SDO also predicts it on the 31.12.2023

http://jsoc.stanford.edu/data/farside/

depends if it decays/grows/stays the same

1 hour ago, Misaka said:

Looks like you are correct with the date. SDO also predicts it on the 31.12.2023

http://jsoc.stanford.edu/data/farside/

depends if it decays/grows/stays the same

and actually farside maps do not show the sunspots. they show active regions so it might be thought it has decayed if we hadn't receive Perseverance imagery

[Philalethes]

14 hours ago, Sapphire828 said:

Did you ever hear back from NASA about the orientation of these pictures and a way to approximate the rotation time?

Nope, nothing. I guess it's not exactly top priority for them, heh.

14 hours ago, Sapphire828 said:

I'll make a rough assumption the sun's equator is vertical in the picture and take the lengths of the red lines.

Full length red line 5.06 units
Shorter red line with the middle sunspot position 3.06 units
Ratio~0.605

Carrington rotation ~27.3 days, half Carrington rotation ~13.65 days
13.65 days*0.605 = 8.25 days from 12/22/23 noon

Dec22.5+8.25=30.75, rounded 31

ETA at East limb ~12/31/23

Good estimate; I guess if the spots are actually moving the other direction the ratio would be ~0.4 instead, and arrival would be in 4-5 days (and for movement in any directions in between it would be somewhere in the middle of that and your estimate, the spots being so close to the center making for less variation).

I would also add that Mars isn't exactly opposite Earth anymore, so using exactly half a Carrington rotation might not be as precise, but it's a rough estimate after all. It's still quite close to half by the looks of it, so should be fine in this case.

11 hours ago, Misaka said:

Looks like you are correct with the date. SDO also predicts it on the 31.12.2023

http://jsoc.stanford.edu/data/farside/

Yeah, looks like a decent estimate. One thing to note is that from it looks to be noticeably offset from the equator, which would mean that it would be unlikely to be that close to the equator as seen from Mars, since we're seeing the Solar tilt almost directly from the side this time of year (which would be roughly opposite for Mars, but still from the side). But given how close the spots are to the center it should be fairly close anyway.

I'm generally skeptical of farside imagery though. Not just in terms of accuracy, but it wouldn't be the first time spots shrink into nothingness before leaving only some plage as they emerge from the limb.

[tniickck]

52 minutes ago, Philalethes said:

 

I'm generally skeptical of farside imagery though. Not just in terms of accuracy, but it wouldn't be the first time spots shrink into nothingness before leaving only some plage as they emerge from the limb.

but this is how it works. plage still makes the sun's surface vibration different

[Philalethes]

48 minutes ago, tniickck said:

but this is how it works. plage still makes the sun's surface vibration different

Areas of plage do have certain activities that "regular" surface areas don't have, but as far as I'm aware they typically tend to signify active regions that have recently decayed, which was what I meant (i.e. that even if there's a strong AR there now there's a good chance it will have decayed before we ever get to see it).

But of course I'd love to be proven wrong. The strongest ARs of all can persist for multiple rotations, but that's rather rare to my knowledge.

[Sapphire828]

On 12/26/2023 at 2:32 PM, tniickck said:

Very nice! yall always provide us with some Mars photos. 

this must be 3514 

 

@tniickck yes, it is likely the 3514 region. There were a few nearby active regions as it went over the limb 3514, 3520, 3517, 3513. I've been watching for new images from Mars, but it seems the rover team is still on Christmas vacation. 12/23/23 is the last set of pictures beamed back to Earth.

 

On 12/27/2023 at 3:42 AM, Philalethes said:

Nope, nothing. I guess it's not exactly top priority for them, heh.

Good estimate; I guess if the spots are actually moving the other direction the ratio would be ~0.4 instead, and arrival would be in 4-5 days (and for movement in any directions in between it would be somewhere in the middle of that and your estimate, the spots being so close to the center making for less variation).

I would also add that Mars isn't exactly opposite Earth anymore, so using exactly half a Carrington rotation might not be as precise, but it's a rough estimate after all. It's still quite close to half by the looks of it, so should be fine in this case.

Yeah, looks like a decent estimate. One thing to note is that from it looks to be noticeably offset from the equator, which would mean that it would be unlikely to be that close to the equator as seen from Mars, since we're seeing the Solar tilt almost directly from the side this time of year (which would be roughly opposite for Mars, but still from the side). But given how close the spots are to the center it should be fairly close anyway.

I'm generally skeptical of farside imagery though. Not just in terms of accuracy, but it wouldn't be the first time spots shrink into nothingness before leaving only some plage as they emerge from the limb.

@Philalethes Thanks, I didn't even think about the Mars/Earth orientation when I used the number of days in a Carrington rotation. I'll have to keep this in mind for the future. I think I understand what you are saying about the closeness to the equator. Hopefully the equatorial line angle can be refined in the future.

It seems like we should be able to figure this out given that we receive consistent solar pics from Mars and a big enough sunspot to track around the limb.

[hamateur 1953]

Kevin at Solar Ham seems to agree with everything so far.   I watch the incoming limb like a hawk of late so if old 3514 is still alive, we should be seeing loops this Saturday I might imagine.  Cool.   Edit:   It was so low-latitude that I assumed it was Southern Hemisphere.  It dealt the X flare at 4 degrees North if anyone else wondered.  

Edited December 29, 2023 by hamateur 1953
Lat.

[Philalethes]

2 hours ago, Sapphire828 said:

@Philalethes Thanks, I didn't even think about the Mars/Earth orientation when I used the number of days in a Carrington rotation. I'll have to keep this in mind for the future. I think I understand what you are saying about the closeness to the equator. Hopefully the equatorial line angle can be refined in the future.

It seems like we should be able to figure this out given that we receive consistent solar pics from Mars and a big enough sunspot to track around the limb.

Yeah, if we got images from several days in a row in which the same spots are visible it would be fairly easy to orient the images correctly along the lines of movement. But even then the same orientation wouldn't necessarily be preserved from image to image, so next time we'd get an image of a new spot we'd be back to needing another image in close temporal proximity.

[Sapphire828]

My estimate held up relatively well. I originally drew the red line starting at the middle of the active region, and I think we are starting to see the first smaller outer edges coming over the east limb today. I thought we would see more of this active region by today but farside data predicts ~2 more days to see the rest of the AR. As @Philalethes stated above the angle of the equator from the Mars pictures likely needs to be refined and it is not expected that you can apply the same method to different pictures (unless there is consistent and frequent pictures sent back from Mars).

@hamateur 1953

@tniickck

[Malisha Reuvekamp]

And another view of the backside.

Looking good.

Edited January 6 by Malisha Reuvekamp

[hamateur 1953]

Indeed @Malisha Reuvekamp  What we have been anticipating and hoping for as well.  Tnx for that! 

[tniickck]

1 hour ago, Malisha Reuvekamp said:

And another view of the backside.

Looking good.

lots of spots, but small ones

[tniickck]

photo from the 5th of Jan. there is a photo from 6th, but it is in white and spots are barely distinguishable

[arjemma]

2 hours ago, tniickck said:

photo from the 5th of Jan. there is a photo from 6th, but it is in white and spots are barely distinguishable

The spots in this image looks rather lame :( 

[Sam Warfel]

7 hours ago, arjemma said:

The spots in this image looks rather lame

The resolution is so poor, the spots do have to be decently large/dark to show up at all. They might not be monsters, but maybe worth a look.
Tiny ones wouldn’t show up at all