ASTRO: Leo III (Leo A)

"Rick Johnson" wrote
.......
Oddly, now that it is 50F degrees warmer the scope has come back into
close collimation. Must be a cold issue in the design. I expect it to be
back to normal in another 10 degrees so haven't touched it. Come summer I
may have to adjust the other way!

Rick,

I'm not surprised. The big shifts in temp we have 'up north' have big
impacts of telescopes in general, including the mounts. It also impacts gear
error as they shrink with the cold. At Kopernik, since it's not my $140
grand telescope, I'm somewhat reluctant to use the scope at a temp below
about 10F degrees because of possible damage to the gears and bearings in
the mount, not to mention the protest sounds that come from the dome when
rotating.

George N

"Rick Johnson" wrote
...
....... Leo III has a population of very
young stars which is odd for a dwarf with so little dust and gas. It
seems to have had several periods of star birth over its lifetime.


Rick,

Great image! Your seeing must have been OK the night you took this one.

I would bet that those red 'stars' in your image are actually small H-II
regions. Otherwise, this galaxy is a neat collection of mostly blue giants!
My guess is that these dwarfs are the remnants of a larger spiral that was
cannibalized by the Milky Way.

George N

George Normandin wrote:

"Rick Johnson" wrote

.......
Oddly, now that it is 50F degrees warmer the scope has come back into
close collimation. Must be a cold issue in the design. I expect it to be
back to normal in another 10 degrees so haven't touched it. Come summer I
may have to adjust the other way!


Rick,

I'm not surprised. The big shifts in temp we have 'up north' have big
impacts of telescopes in general, including the mounts. It also impacts gear
error as they shrink with the cold. At Kopernik, since it's not my $140
grand telescope, I'm somewhat reluctant to use the scope at a temp below
about 10F degrees because of possible damage to the gears and bearings in
the mount, not to mention the protest sounds that come from the dome when
rotating.

George N

While possibly true of Leo I and II this guy is at about the same
distance as M31 but in the opposite direction so I doubt he's had much
if any cannibalism. From what I can read on this guy it's had several
rounds of star formation, the last not all that long ago, hence the blue
"stars". I'm not sure if those are individual stars or more likely
massive clusters of blue stars. The last major round of star formation
was too long ago for the O and B stars to still be around. Late A might
have a chance to still be there but you'd need a cluster of them to show
as bright as the knots do at that distance.

Rick

--
Correct domain name is arvig and it is net not com. Prefix is correct.
Third character is a zero rather than a capital "Oh".

Rick,

amazing shot. I'll have to find out where this galaxy is, though I would
guess that it is not suitable for city skies...

Stefan

"Rick Johnson" schrieb im Newsbeitrag
...
After Leo I and Leo II comes Leo III. Why Leo II is also known as Leo B
but Leo III is Leo A I can't fathom. Leo III has a population of very
young stars which is odd for a dwarf with so little dust and gas. It
seems to have had several periods of star birth over its lifetime.

Leo I is a over 800 thousand light years away and Leo II 750 thousand
light years. They are satellites of our galaxy. Leo III however is 2.5
million light years away so a member of our local group but not a
satellite galaxy. Still, thanks to those young massive stars I was able
to resolve quite a few of its stars.

I tried something new when imaging this guy. I used 3x3 binning on the
color frames. Otherwise, through the filters I'd have needed a lot of
exposure time to capture the color of the faint stars. This allowed me
to use half the exposure time and still resolve the stars through the
filters. It turned out well so I may do this more often and save some
imaging time.

14" LX200R@f/10, L=4x10' binned 2x2, RGB=2x10' binned 3x3, STL-11000XM,
Paramount ME

Rick
--
Correct domain name is arvig and it is net not com. Prefix is correct.
Third character is a zero rather than a capital "Oh".

09h 59m 26s +30d 44m 47s is where my FITS header says the scope was
pointed. That's usually within a second or two of the catalog position.

Rick


Stefan Lilge wrote:

Rick,

amazing shot. I'll have to find out where this galaxy is, though I would
guess that it is not suitable for city skies...

Stefan

"Rick Johnson" schrieb im Newsbeitrag
...

After Leo I and Leo II comes Leo III. Why Leo II is also known as Leo B
but Leo III is Leo A I can't fathom. Leo III has a population of very
young stars which is odd for a dwarf with so little dust and gas. It
seems to have had several periods of star birth over its lifetime.

Leo I is a over 800 thousand light years away and Leo II 750 thousand
light years. They are satellites of our galaxy. Leo III however is 2.5
million light years away so a member of our local group but not a
satellite galaxy. Still, thanks to those young massive stars I was able
to resolve quite a few of its stars.

I tried something new when imaging this guy. I used 3x3 binning on the
color frames. Otherwise, through the filters I'd have needed a lot of
exposure time to capture the color of the faint stars. This allowed me
to use half the exposure time and still resolve the stars through the
filters. It turned out well so I may do this more often and save some
imaging time.

14" LX200R@f/10, L=4x10' binned 2x2, RGB=2x10' binned 3x3, STL-11000XM,
Paramount ME

Rick
--
Correct domain name is arvig and it is net not com. Prefix is correct.
Third character is a zero rather than a capital "Oh".



--
Correct domain name is arvig and it is net not com. Prefix is correct.
Third character is a zero rather than a capital "Oh".

"Martin C Germano" wrote in message
ink.net...
Hi Scott, and all ....

WOW! That's a dwarf galaxy if I ever saw one. I bet Marty Germano would
love to see this image!

I see and am amazed! It's really wonderful what ccd's can do. Rick's image
actually resolves the *stars* in Leo III ... way better than my 14.5" Newt
and Tech Pan.

-- Marty

Hi Marty! Hope all is well for you and family. Haven't seen
you posting much since you went over to the dark side :^).

Scott