How far to small galaxies near M51?

[PhotoGav]

I am trying to find out how far away the two galaxies, IC4277 & IC4278, are and I am failing miserably. They are the two magnitude 15 or so galaxies visible just near to The Whirlpool Galaxy, M51. Now, M51 is about 23 million light years away, so these two little (well, apparently little!), galaxies must be way further than that...

If anyone can help with this, I would be thrilled.

Thank you,

Gav.

[Stu]

Gav, SkySafari doesn't list a distance for either of these two. Perhaps it is not known very well?

It lists M51 at 27 million Light Years.

[PhotoGav]

That is what I have found too. There are no references on the Internet at all to the possible distances to these two. The only thing I've found is a wild guess at 650 million light years! The EdgeHD 800 is doing well if that's the case...

[symesie04]

I guess its possible that their respective distances have yet to be calculated. Maybe the foreground heavy weights distort any attempts to accurately measure their distances.

[Martin Meredith]

I have an estimate of 250 MLY for IC4278 (from LEDA)

IC 4277 I can't find...

Martin

[edit: and a magnitude of 17.2]

[dph1nm]

IC4278 has a spectrum from SDSS

http://skyserver.sdss.org/dr12/en/get/SpecById.ashx?id=1647338399901706240

IC4277 was not picked up in SDSS at all, I guess due to its proximity to M51.

NIgelM

[Tinker1947]

There both shown in Sky Safari 4 Pro IC 4278  size 0.5 x 0.3 Arcmin, mag 15.39 also has a PGC 2294807 reference, IC 4277 size 0.9 x 0.1 arcmin, Mag 15.69, no PGC Number, neither have a distance shown, IC 4282 is also close bye.

[PhotoGav]

Thank you for the responses... It does seem that nobody really currently knows.

Nigel - I am intrigued to know how that information might help in working out a distance? I hope that it does!

[dph1nm]

Nigel - I am intrigued to know how that information might help in working out a distance? I hope that it does!

The redshift, z,  is on the top of the plot of the spectrrum: z=0.01672. You can then (roughly) get the distance from c*z/H_0, where c is the speed of light and H_0 is your favourite value of Hubble's constant. Or you can just go to http://www.astro.ucla.edu/~wright/CosmoCalc.html and feed in 0.01672 as z. Either way you get around 240 million light-years.

NIgelM

[PhotoGav]

The redshift, z,  is on the top of the plot of the spectrrum: z=0.01672. You can then (roughly) get the distance from c*z/H_0, where c is the speed of light and H_0 is your favourite value of Hubble's constant. Or you can just go to http://www.astro.ucla.edu/~wright/CosmoCalc.html and feed in 0.01672 as z. Either way you get around 240 million light-years.

NIgelM

Excellent, that is exactly what I was after. Thank you, thank you!

And wow, that is pretty darn distant.

[PhotoGav]

A little update...

After plugging in the numbers, my colleague and I have settled on a figure of 230 million light years to IC4278. Why is this of interest? Well, I am currently holding an exhibition of astrophotography in Marlborough and have been merrily telling everyone that the most distant object on display is M51, at 23 million light years away. However, in the picture, just below M51, is a faint smudge, definitely not a star, definitely a Galaxy... IC4278, now estimated, with thanks to your help, to be 230 million light years away, ten times more distant. That's neat. However, the really beautiful coincidence is the value for the galaxy's red shift, 0.01672. Why is that beautiful? The dialling code for Marlborough is 01672 !!!!

Gotta love beautiful numbers!

[Jim78154]

I am trying to find out how far away the two galaxies, IC4277 & IC4278, are and I am failing miserably. They are the two magnitude 15 or so galaxies visible just near to The Whirlpool Galaxy, M51. Now, M51 is about 23 million light years away, so these two little (well, apparently little!), galaxies must be way further than that...

If anyone can help with this, I would be thrilled.

Thank you,

Gav.

Just out of curiosity, why do you want to know this? If you are planning a trip, may I come along?

[PhotoGav]

Just out of curiosity, why do you want to know this? If you are planning a trip, may I come along?

Hee hee!

As for why:

A little update...

After plugging in the numbers, my colleague and I have settled on a figure of 230 million light years to IC4278. Why is this of interest? Well, I am currently holding an exhibition of astrophotography in Marlborough and have been merrily telling everyone that the most distant object on display is M51, at 23 million light years away. However, in the picture, just below M51, is a faint smudge, definitely not a star, definitely a Galaxy... IC4278, now estimated, with thanks to your help, to be 230 million light years away, ten times more distant. That's neat. However, the really beautiful coincidence is the value for the galaxy's red shift, 0.01672. Why is that beautiful? The dialling code for Marlborough is 01672 !!!!

Gotta love beautiful numbers!

[Guest]

The main source for most galaxy information can be found here

https://ned.ipac.caltech.edu/

You can out the name in and it will give you what information it has. In your case very little.

Owen

[PhotoGav]

Thank you Owen, though as you say, not much info there really!