Needing help identifying contrail ... thanks!

[I_Gaze_At_The_Blue]

I am currently engaging in a Facebook group with someone who posted this image and claims it is at a "low" altitude, stating it is less than 10,000 feet, which he says is impossible for a contrail to form. After much discussion, he has stated it was taken in Cairns, Australia, on May 31st at around 13:00.

His actual words : (Chemtrail photo taken Cairns Fri May 30th, 1pm, met temp 20degrees centigrade, humidity 70 degrees.)

I don't have any accounts on any of the flight trackers, so I was wondering (pretty please ) if any of you guys could do the honours, for I am positive it is not as "low" as he claims, and many of you have the skills to be able to find out.

Many thanks for any help; it would be much appreciated!

 

[Mendel]

May 30th or May 31st?
Ideally we'd want the exact time from the image file or its metadata.

 

[Mendel]

Cairns is on GMT+10, so 1pm translates to 03:00 UTC.

I checked https://himawari8.nict.go.jp/ to see if I could find the contrail. May 31st 3:00 was cloudless over the continent, May 30th has contrails:
May 31:

May 30:

It would be great if someone could double-check this.

 

[flarkey]

There's not a lot of high altitude traffic over Cairns around that date time (Fri 30 May 0300UTC ± 1 hr). The closest I could get was this A321 at 34,000 ft at 0335UTC = 1335local. It would be good if you could get the exact time of the photo as "1pm" leaves quite a bit of wiggle room.

(this is filtered to only show aircraft over 10,000 ft.)

https://globe.adsbexchange.com/?replay=2025-05-30-03:35&lat=-17.127&lon=145.877&zoom=8.9

 

[FatPhil]

...claims it is at a "low" altitude, stating it is less than 10,000 feet...

What's his evidence for this claim? What were his inputs, what were his calculations?

 

[Mick West]

claims it is at a "low" altitude, stating it is less than 10,000 feet, which he says is impossible for a contrail to form.

People often mistake closeness to the horizon for altitude. I had a case via email which was clearly the ISS, and I showed this (with a nice Sitrec recreation), but they rejected this as they thought what they saw was "too low".

the contrail look like it's about 5-19 minutes old, and will have drifted a bit with the wind, and not exactly follow the track. But if you can get the exact time, location, and direction (probably NE), then we can probably find the plane.

 

[cloudspotter]

What's his evidence for this claim? What were his inputs, what were his calculations?

And why don't ANY of the people making low altitude trail claims EVER get a photo of the low altitude aircraft leaving these trails?

 

[Trailblazer]

The relative humidity at 250mb (34,000ft) was actually fairly low over Cairns at that time according to earth.nullschool.net:

Slightly higher further south but still below 30%. A full sounding would be useful: I would expect to see higher humidity at either higher or lower altitudes, say 200mb or 300mb.

 

[Trailblazer]

Here is the GFS modelled sounding for 0000UTC on 30 May. It runs in six hourly steps and the 0600UTC sounding is similar.

It shows the highest humidity at the 150mb level, which is about 44,000 feet in a standard atmosphere - above the top of cruising range for most planes, except private jets.

So based on that I would look at the highest planes around that time.

JST47 is the highest I can see at 38,000ft, around 1.30pm local time.

Given the possible confusion of date in the OP, I also looked at 31 May. The soundings actually look very similar, with the highest humidity again being right at the top end of the cruising window. If the photographer got his date wrong, this is a possibility, at 39,000ft, passing over Cairns just after 12.30pm on the 31st.

 

[psikiwi]

After much discussion, he has stated it was taken in Cairns, Australia, on May 31st at around 13:00.

After much discussion, he should have been able to check the file for the exact time, no? And perhaps also have given a more 'specific' approximate location (i am aware people don't want to auto-dox), and direction of his shot. If this conversation you've had is like pulling teeth, is he arguing in bad faith?

 

[Trailblazer]

I'm a bit confused by the date of the satellite images on Nasa Worldview.

The orange and pink lines show the time (in UTC) of the satellite passes. But if I choose May 30 as the date at the bottom, it seems to be showing a Terra pass close to midnight of May 31 (23:56 UTC May 30) which would be around 10am on May 31 local time.
I suppose there has to be a point on the globe at which the imagery jumps from one day to the next.

But I think it means that to get Terra images for May 30 in Cairns you need to select May 29 as the date... this would be 9.16am on May 30.

 

[Mendel]

I'm a bit confused by the date of the satellite images on Nasa Worldview.

The confusion goes away if you first convert the local time and date to UTC, as I did above.

Cairns is on GMT+10, so 1pm translates to 03:00 UT

That is on the same date.

If that does not address your issue, could you please explain more?

 

[Trailblazer]

The confusion goes away if you first convert the local time and date to UTC, as I did above.

That is on the same date.

If that does not address your issue, could you please explain more?

I mean that on Worldview, if you choose a given date in the slider at the bottom, you don't necessarily get images taken on that date.

Looking at it again, it seems to depend on which Australia you look at on the map!
Australia appears at both left and right of the world map.

With the date set to May 30...

the "west" Australia has images taken late on May 30 or even early on May 31 UTC, so May 31 local time, while the "east" Australia has images taken late May 29 / early May 30 UTC, so May 30 local time.

I had scrolled to the left/west Australia, so I was a day out initially.

 

[Mendel]

I mean that on Worldview, if you choose a given date in the slider at the bottom, you don't necessarily get images taken on that date.

Ah, I see! That's because they put consecutive passes next to each other!
So when they start on a certain time in Greenwich, the timing of the satellite passes going east and west goes in opposite directions.
This procedure avoids "jumps", but then the date may be off.

 

[I_Gaze_At_The_Blue]

What's his evidence for this claim? What were his inputs, what were his calculations?

Of course he never gave any, just the vague claim of Cairns around 13:00 and his"insistence" he could tell it was less than 10,000 feet. It's impossible to pin these people down to details.

 

[I_Gaze_At_The_Blue]

After much discussion, he should have been able to check the file for the exact time, no? And perhaps also have given a more 'specific' approximate location (i am aware people don't want to auto-dox), and direction of his shot. If this conversation you've had is like pulling teeth, is he arguing in bad faith?

He keeps insisting it is low altitude, less than 10,000 feet and just won't let it go, since he won't provide more details, then it is virtually impossible to get him to change his mind. I have posted various things about optical illusions to try to get him to realise the human eye is not good at judging things like altitudes correctly, but he is stuck just saying it's "low altitude". I rather suspect that he knows deep down to do so would prove him wrong and, as it typical for these people, he just cannot accept that.

 

[I_Gaze_At_The_Blue]

People often mistake closeness to the horizon for altitude. I had a case via email which was clearly the ISS, and I showed this (with a nice Sitrec recreation), but they rejected this as they thought what they saw was "too low".

the contrail look like it's about 5-19 minutes old, and will have drifted a bit with the wind, and not exactly follow the track. But if you can get the exact time, location, and direction (probably NE), then we can probably find the plane.

Would love to get him to give more details, but he is insistent on just saying it is "low" altitude.

I rather suspect, too, that you are right and he is mistaken about the angle of the contrail and so thinking it is low. I have already shown him images of powerlines appearing to go downwards, and how issues of perspective can be misleading, but he insists he is right and it is "low", and so less than 10,000 feet. But he refused to give any more details, which I know is because he knows he was shown wrong by me and others in the thread, but cannot face it.

Your help is very, very much appreciated guys ... you guys rock!!!

 

[cloudspotter]

Of course he never gave any, just the vague claim of Cairns around 13:00 and his"insistence" he could tell it was less than 10,000 feet. It's impossible to pin these people down to details.

Numerous photos and a prevalence of low altitude trails but nobody ever thinks to get a good quality video of the aircraft leaving the trails, including buildings or terrain to show they are too low. Odd that.

 

[Jay Reynolds]

it is virtually impossible to get him to change his mind.

There isn't enough information here to change anyone's mind. Generally a person changes their own mind, if they are open enough.