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Tadpoles Nebula with mysterious moving objects - please help!

gorann

By gorann
in Imaging - Deep Sky

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gorann

gorann

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Finally, last night the sky cleared and I managed to get 2 hours on the Tadpoles Nebula (12 x 10 min, 5 " ES apo with a Canon 60Da at 1600 ISO). Not great so I decided to spice it up with some luminosity from the POSS2 sky survey data (monochrome red filtered data collected on glass plates) that are freely available on the DSS site. The POSS2 data is about 20 years old. To my surprise, I noticed that at least two stellar objects had moved from then to now. They look like stars (one of them look like two closely situated stars). But if they are stars they must be very close to us to move in such a short time. I would expect that stars being that close also should be quite bright but these are not.

Any ideas anyone? Can anyone identify these things?

I post the RGB image with the POSS2 added to parts of it as lum, and then B/W images where I have marked out the mysterious objects. The large one is a 50:50 mix of the two images, where arrows point at the moving objects. In the four small panels I have zoomed in on the moving objects and marked them.  By the way, it also looks like POSS2 captured an asteroid.

IMG2453-64PS2+POSSPS5cropSign.jpg

IMG2453-64 + POSS2 comparisonText.jpg

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jabeoo1

jabeoo1

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Satellites?  I just looked on the redshift software and lots of satellites swim though Auriga.  I am guessing they are 2 different satellites?

What time did you start the capture and what time did you finish it ?  I am be able to back track what passed thought during that time period. 

I notice also on your 1st main image: If you look slightly right of centre line from bottom, around 1/3rd of the way up there is a line of light?  Is this a moving object too? 

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gorann

gorann

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15 minutes ago, jabeoo1 said:

Satellites?  I just looked on the redshift software and lots of satellites swim though Auriga.  I am guessing they are 2 different satellites?

What time did you start the capture and what time did you finish it ?  I am be able to back track what passed thought during that time period. 

I notice also on your 1st main image: If you look slightly right of centre line from bottom, around 1/3rd of the way up there is a line of light?  Is this a moving object too? 

 

8 minutes ago, Shibby said:

It's quite possible that you'd notice some proper stellar motion in that time! They could well be small, dim, nearby stars. They won't be satellites because they'd appear as trails.

Friends,

Like Shibby I also excluded satellites since they usually are trails and at least they would have moved more than a few arc seconds in 20 years. If they are close by stars, why are they not brighter? Also, the two "stars" together are particularly odd. I hope some skilled person can find these objects in some database.

I will be out imaging tonight (clear skies!!) so I may be a bit slow in responding.

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Uranium235

Uranium235

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39 minutes ago, Shibby said:

It's quite possible that you'd notice some proper stellar motion in that time! They could well be small, dim, nearby stars. They won't be satellites because they'd appear as trails.

Blimey! Back from the dead :) haven't seen you about in ages mate (pardon the digression).

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gorann

gorann

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6 hours ago, SilverAstro said:

 most interesting presentation, thank you.

are there  any surveys online from the 70s or 80s ?

 

Yes, good idea, there is a POSS1 from the 50ties - I will check it!

Tanks!

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beka

beka

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Hi Gorann, very interesting observation. I think that if they are satellites, this much movement over 20 years would have to mean almost geostationary. Geostationary satellites would be over the equator so my guess is that the location of  the Tadpole does not match this. The other possibility might be KPO's  or comets with long orbital periods. However I tend to favour the explanation that the movements are the due to proper motion of the stars. This much movementioned is definitely possible over 20 years. It can also be observed for members of binary pairs. I think it is very interesting to follow up.

All the best!

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gorann

gorann

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11 hours ago, beka said:

Hi Gorann, very interesting observation. I think that if they are satellites, this much movement over 20 years would have to mean almost geostationary. Geostationary satellites would be over the equator so my guess is that the location of  the Tadpole does not match this. The other possibility might be KPO's  or comets with long orbital periods. However I tend to favour the explanation that the movements are the due to proper motion of the stars. This much movementioned is definitely possible over 20 years. It can also be observed for members of binary pairs. I think it is very interesting to follow up.

All the best!

 

10 hours ago, Star101 said:

Its funny you should mention this. In another forum a few moments ago, a discussion of a Hubble image of a supernova from years ago compared to today.

http://www.astronomyforum.net/astrophysics-forum/230919-hubble-revisits-sn1987a.html

Things do move out there :D

 

4 hours ago, ultranova said:

Very nice catch, hope you get to the bottom of it

Nice tadpole as well

Paul

 

I have now also checked the POSS1 survey from the 1950ties, and yes, the objects are there but have moved !! (or rather they have later moved). I now also got the dates from the fits infofiles:

POSS1 image: 1954.12.29

POSS2 image: 1988.12.01

My image: 2017.02.24

I also tried to measure how many arcminutes they moved and the star like object to the left has moved about 0.75 arcminutes and the object to the right 0.25 arcminutes in about 62 years.

I assume that the object to the left is most likely a small  close by star, but the object to the right is quite mysterious since it looks like a double star but the angle between the "stars" is the same in all three images so apparently they do not rotate. Sill they are apparently connected by gravity since they move together but my idea of Newtonean mechanics is that at least one of them would need to rotate around the other or they would crash into each other.

Here are some more images. The first show an overlay of all three images, where the arrows point out these objects moving from right to left from 1954 to now. The second image is made up of three panels showing crops of the double star-like object from 1954, 1988 and 2017.

It would be really cool if anyone knows a way to figure out what these objects are from searching in catalogues / surveys.

Now+POSS1+2 Arrows.jpg

POSS1+2+Now cropBText.jpg

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SilverAstro

SilverAstro

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14 hours ago, gorann said:

Yes, good idea, there is a POSS1 from the 50ties - I will check it!

Tanks!

I thought I remembered one being done by the 48in Schmidt at Palomar, didnt realise it was that long ago and that it was now online , how time flies :)

Nice find,

and you are right about "Newtonean mechanics is that at least one of them would need to rotate around the other or they would crash into each other. " and Kepler. Technically they both revolve about a common point (the barycenter, pse excuse if I am teaching eggs ) which, if they are of the same mass will by half way between. They may not detectably revolve round each other in this period depending on how far apart they are, (Kepler has a lot to say about that) but they could still be hurtling through space at a detectable rate depening on ,, well lots of things ! :)

 

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SilverAstro

SilverAstro

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56 minutes ago, gorann said:

It would be really cool if anyone knows a way to figure out what these objects are from searching in catalogues / surveys.

Sorry dont know a way, but meanwile I propose that they be called Goran I and Goran II in the New SGL Catalogue of Anomolous Stellar Objects :)

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gorann

gorann

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3 minutes ago, SilverAstro said:

I thought I remembered a one being done by the 48in Schmidt at Palomar, didnt realise it was that long ago and that it was now online , how time flies :)

Nice find,

and you are right about "Newtonean mechanics is that at least one of them would need to rotate around the other or they would crash into each other. " and Kepler. Technically they both revolve about a common point (the barycenter, pse excuse if I am teaching eggs ) which, if they are of the same mass will by half way between. They may not detectably revolve round each other in this period depending on how far apart they are, (Kepler has a lot to say about that) but they could still be hurtling through space at a detectable rate depening on ,, well lots of things ! :)

 

I have done a bit more research about moving stars. The fastest moving one (in angle seen from Earth) is Barnard's star, about 6 light years away. It moves 10.3 arcseconds/year, which corresponds to half a mood diameter in a human life time!

The fastest moving object in my image moves about 0.75 arcs / year, so quite a bit slower than Bernard (14 times) and my odd "double star" moves about 0.25 arcs /year = 40 times slower than Bernard's star. If that "double star" moves (in km/s) as fast as Bernards (which moves laterally at 90 km/s), it would be 40 x 6 = 240 light years away. However, it is probably closer since Bernard's star is moving unusually fast. You have a point regarding the possibility that the two components in the possible double star are circulating very slowly, but it somehow sounds too slow for me.

I may send an e-mail to some astrophysicist at the University of Oslo where I work as a biologist. There are probably not that much exchange of questions between our departments so it could be fun.

I downloaded the POSS 1 (1950.07.09) and POSS2 (1991.06.16) images of Bernard's star to see for myself. Measuring the speed on the images gave me exactly 10.3 arcs/year (just like in Wikipedia!). Here are the POSS1 and POSS2 images superimposed, with Bernard in red:

POSS1+2 Barnards red crop.jpg

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gorann

gorann

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8 minutes ago, SilverAstro said:

Sorry dont know a way, but meanwile I propose that they be called Goran I and Goran II in the New SGL Catalogue of Anomolous Stellar Objects :)

That would be something!

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beka

beka

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Entertaining the KBO or comet theory, the longest period comet so far seems to be Comet West with a period of 250000 years! A rough calculation gave me about 5 arcminutes motion over 60yrs (360/250000 degrees/year then × 60 for arcminutes/year and again by 60 for 60 years). The movements of the objects in your observation would then be too small for a solar system body even of such a long orbital period as this. What would be the magnitude's of these objects?

Best

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SilverAstro

SilverAstro

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26 minutes ago, gorann said:

but it somehow sounds too slow

Au contraire ! We know of lots of multiple stars that take many hundreds of years to orbit, how about Proxima Centaurus which may take about 1/2million years to complete an orbit, (so long in fact that for many years it was debatable if it was part of the system. )

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gorann

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On 2017-02-25 at 16:55, SilverAstro said:

Au contraire ! We know of lots of multiple stars that take many hundreds of years to orbit, how about Proxima Centauri which may take about 1/2million years to complete an orbit, (so long in fact that for many years it was debatable if it was part of system. )

You are probably right, it was just counter-intuitive for me, but then intuition is probably not very useful in cosmology....

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SilverAstro

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41 minutes ago, SilverAstro said:

 I propose that they be called Goran I and Goran II in the New SGL Catalogue of Anomolous Stellar Objects :)

 

28 minutes ago, gorann said:

That would be something!

Or even Goran I, and Goran IIa & Goran IIb ?  :)  would save on "the object to the left " etc :D Note I chose Anomolous since  "Quasi Stellar " has been taken already :icon_cry:

Good luck with your astro dept.

 

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gorann

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11 minutes ago, SilverAstro said:

I wonder if this might help ?

PPM - Positions and Proper Motions Catalog  http://heasarc.gsfc.nasa.gov/W3Browse/star-catalog/ppm.html

 

 

2 minutes ago, beka said:

Hi SilverAstro, It looks like this catalog is only to magniude 7.5. These objects look to be much fainter.

Yes, they would be much fainter, taken with a 5" scope and 10 min exposure, they are nothing that can be seen by a naked eye through that scope. So probably around mag 14 or less, but that is very much a guess, but sadly much less than 7.5 at least

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SilverAstro

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9 minutes ago, beka said:

Hi SilverAstro, It looks like this catalog is only to magniude 7.5. These objects look to be much fainter.

Good point !

how about XMR ooops  XPM  at VizieR http://cdsarc.u-strasbg.fr/viz-bin/Cat?I/319

I think we need Martin @Martin Meredith of this parish, he is good with catalogues and faint things ! :)

 

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