Epsilon Lyrae - - what am I missing?

I am missing something here. I'm a beginner and am still trying to split
the double-double in Epsilon Lyrae.

"Skywatching" by David Levy tells me that the slightest optical aid shows
two stars of equal magnitude just west of Vega and that a 4-inch scope at
100X splits these into a double each.

"Turn Left at Orion" says essentially the same thing.

I put Vega at the top of the field of view in 10x50 binos and at the bottom
of the FOV, generally west of Vega, are two stars of equal magnitude. I
locate these in my 8-inch Dob and run them up to 100X, 171X, 240X and still
no split that I can tell. Do I have the wrong pair or are they not that
simple?

I have a copy of the Will Tirion SkyAtlas 2000 that I am still figuring out
how to use. As best I can tell, I am seeing the two stars at: chart 8, one
of the stars is at approx 19h15m RA, +39d10m decl and the two stars are
numbered 20 and 21. Is this pair the double-double?

Thanks.

--

----
Joe S.

"Joe S." wrote in message
...

I am missing something here. I'm a beginner and am still trying to split
the double-double in Epsilon Lyrae.

Both doubles are very tight, and at a right angle to each other. I couldn't
see them either when I first started.

I routinely nail stuff today that I couldn't see at all 20 years ago - and
you *know* my vision isn't any better! 8)

----
Dave Boll
http://www.daveboll.com/

"Joe S." wrote in message
...
I am missing something here. I'm a beginner and am still trying to split
the double-double in Epsilon Lyrae.

"Skywatching" by David Levy tells me that the slightest optical aid shows
two stars of equal magnitude just west of Vega and that a 4-inch scope at
100X splits these into a double each.

"Turn Left at Orion" says essentially the same thing.

I put Vega at the top of the field of view in 10x50 binos and at the
bottom
of the FOV, generally west of Vega, are two stars of equal magnitude. I
locate these in my 8-inch Dob and run them up to 100X, 171X, 240X and
still
no split that I can tell. Do I have the wrong pair or are they not that
simple?

I have a copy of the Will Tirion SkyAtlas 2000 that I am still figuring
out
how to use. As best I can tell, I am seeing the two stars at: chart 8,
one
of the stars is at approx 19h15m RA, +39d10m decl and the two stars are
numbered 20 and 21. Is this pair the double-double?


West?..I always go to the 11 o'clock position to the two stars that look
like 2 headlights. I can just split them at 180 X's. This is barely a
split however and not what I would call clean
with an 80mm...

Joe S. wrote:
I am missing something here. I'm a beginner and am still trying to split
the double-double in Epsilon Lyrae.

"Skywatching" by David Levy tells me that the slightest optical aid shows
two stars of equal magnitude just west of Vega and that a 4-inch scope at
100X splits these into a double each.

"Turn Left at Orion" says essentially the same thing.

I put Vega at the top of the field of view in 10x50 binos and at the bottom
of the FOV, generally west of Vega, are two stars of equal magnitude. I
locate these in my 8-inch Dob and run them up to 100X, 171X, 240X and still
no split that I can tell. Do I have the wrong pair or are they not that
simple?

Epsilon Lyra is precisely considered a good "informal" test of your
scope's collimation -- if you can resolve the double-double, then
collimation is fine. If not, then either collimation is not fine,
or the seeing is not fine at the moment you're seeing it.

I'm not sure I follow your explanation (west of Vega? if my visual
memory doesn't fail me, I believe epsilon is located east of Vega);
but still, I think you are seeing the right pair -- if both fit
within the FOV at more than 150X, then it should be the right pair.

An ASCII-art of Lyra showing where they a


* X


x

x




x

x


The capital X is Vega, and the asterisk (the * character) is your
double-double. Again, I'm doing this from "visual memory", so it
is possible that I got it wrong -- but usually it's pretty obvious
with binoculars, and it's equally obvious with your telescope's
viewfinder (should be a 8x or 10x I guess).

My guess is that either the seeing conditions were not good, or
your collimation is not perfect. A third possibility is that
your eyesight is less-than-optimal (I can not know if that is
the case, but good eyesight certainly plays a role). With an
8 inches, I believe your eye has to make an effort to tell the
four stars (at least that was the case the *one* occasion where
I could see them through my 8 inches Newtonian).

Stay tuned, as I'm sure some much more experienced people
will give you valuable hints, and possibly correct me if I've
gotten some details wrong.

Cheers,

Carlos
--

In article , Joe S. wrote:

I put Vega at the top of the field of view in 10x50 binos and at the bottom
of the FOV, generally west of Vega, are two stars of equal magnitude. I
locate these in my 8-inch Dob and run them up to 100X, 171X, 240X and still
no split that I can tell. Do I have the wrong pair or are they not that
simple?

You can confuse zeta Lyrae with epsilon Lyrae. Through the finder
epsilon is a wide, equal pair but zeta is a tight, uneqal pair.

MANY THANKS to all for your comments and encouragement.

East, West, what's the difference :-) It's up there somewhere.

Based on what everyone has said, I have been looking at the correct pair of
stars.

For the past two weeks I've been hauling my dob around to public Mars
viewings. I dragged it out a few minutes ago and checked collimation --
which was spot on two weeks ago. Well, it's not on any longer -- must have
bounced it around a bit too much. I'll let it cool down tonight, collimate
it, then take a shot at E Lyrae.

--

----
Joe S.

"Joe S." wrote in message
...
I am missing something here. I'm a beginner and am still trying to split
the double-double in Epsilon Lyrae.

"Skywatching" by David Levy tells me that the slightest optical aid shows
two stars of equal magnitude just west of Vega and that a 4-inch scope at
100X splits these into a double each.

"Turn Left at Orion" says essentially the same thing.

I put Vega at the top of the field of view in 10x50 binos and at the
bottom
of the FOV, generally west of Vega, are two stars of equal magnitude. I
locate these in my 8-inch Dob and run them up to 100X, 171X, 240X and
still
no split that I can tell. Do I have the wrong pair or are they not that
simple?

I have a copy of the Will Tirion SkyAtlas 2000 that I am still figuring
out
how to use. As best I can tell, I am seeing the two stars at: chart 8,
one
of the stars is at approx 19h15m RA, +39d10m decl and the two stars are
numbered 20 and 21. Is this pair the double-double?

Thanks.

--

----
Joe S.

On Mon, 1 Sep 2003 10:05:02 -0400, "Joe S."
wrote:

I am missing something here. I'm a beginner and am still trying to split
the double-double in Epsilon Lyrae.

"Skywatching" by David Levy tells me that the slightest optical aid shows
two stars of equal magnitude just west of Vega and that a 4-inch scope at
100X splits these into a double each.

"Turn Left at Orion" says essentially the same thing.

I put Vega at the top of the field of view in 10x50 binos and at the bottom
of the FOV, generally west of Vega, are two stars of equal magnitude. I
locate these in my 8-inch Dob and run them up to 100X, 171X, 240X and still
no split that I can tell. Do I have the wrong pair or are they not that
simple?

I have a copy of the Will Tirion SkyAtlas 2000 that I am still figuring out
how to use. As best I can tell, I am seeing the two stars at: chart 8, one
of the stars is at approx 19h15m RA, +39d10m decl and the two stars are
numbered 20 and 21. Is this pair the double-double?

Thanks.

It sounds like you are looking too far away from Vega. If your 10x50
binoculars have a 5 degree field of view, and if you center Vega in
the middle of the binocular field, Epsilon Lyrae should be to the
West of Vega, well within the binocular field (about 1.6 degrees West
of Vega.)

Look at this picture I made from 'Earth Centered Universe':

http://home.swbell.net/kh6idf/elyra.GIF

In binoculars you can see what looks like a double, easily split
in 10x50 binoculars. They are both about magnitude 5, and should
be really obvious, there are no other bright double stars in that
binocular field.

You should be able to split each one into two at around 100X,-150X and
you will know you have the right ones if they look like this:


* *






*
*


One of the doubles is more or less at right angles to the other.

It requires fairly good seeing to split them because each pair has
about a 2.5 arc-second spacing between the stars. If the seeing
is bad, like worse than 3 arc-seconds or so the two close stars in
each pair would just look like one big fuzzy star. Also your
dobsonian should be well-collimated. I've seen mis-collimated
C-8's that can't split them at all, but even a 60mm refractor can
split them if the lens is good. A decent 8 inch dob should split
them really easily. If the seeing is good, the more power the better.
Once you find them, the 240X eyepice should give a nice view.

good luck,

Fred
Houston, TX
Fred
Houston, TX
remove capitals from email address to reply

"Joe S." wrote in message

As best I can tell, I am seeing the two stars at: chart 8,
one
of the stars is at approx 19h15m RA, +39d10m decl and the two stars are
numbered 20 and 21. Is this pair the double-double?


NO Joe, those are not the right stars. You want 4 e1 and 5 e2, much
closer to Vega.

Good luck,

edz

Take a look when Vega is transiting, Epsilon Lyrae is a little
northeast of Vega.

Seeing two stars is easy. Splitting Epsilon Lyrae into four
stars requires a night of reasonably good seeing and a telescope
that is well collimated, well cooled down, and has reasonably good
optics.

Small refractors can often easy split Epsilon Lyrae but the Newt set up
a few feet away can have a hard time showing more than two elongated
blobs because of the problems mentioned above.

Good luck,
Rich

Joe S. wrote in message ...
I am missing something here. I'm a beginner and am still trying to split
the double-double in Epsilon Lyrae.

"Skywatching" by David Levy tells me that the slightest optical aid shows
two stars of equal magnitude just west of Vega and that a 4-inch scope at
100X splits these into a double each.

"Turn Left at Orion" says essentially the same thing.

I put Vega at the top of the field of view in 10x50 binos and at the bottom
of the FOV, generally west of Vega, are two stars of equal magnitude. I
locate these in my 8-inch Dob and run them up to 100X, 171X, 240X and still
no split that I can tell. Do I have the wrong pair or are they not that
simple?

I have a copy of the Will Tirion SkyAtlas 2000 that I am still figuring out
how to use. As best I can tell, I am seeing the two stars at: chart 8, one
of the stars is at approx 19h15m RA, +39d10m decl and the two stars are
numbered 20 and 21. Is this pair the double-double?

Thanks.

--

----
Joe S.

I split it tonight with my N11 (no great feat), with a 140x (19mm Panoptic.
I needed 200x (14 mm Radian) to get black sky between the close doubles. My
scope was a little miscollimated, doubles are great for pointing that out.
I recollimated a bit at 580x and went back to the double/double. Still
needed 200x to see black between them but the views were a bit more
pleasing. Must be something to split these with a 3" refractor ...


"Jon Isaacs" wrote in message
...
Joe:

Not sure you are looking at the right pair. There are a couple of pairs
in the
neighborhood, easy to get the wrong one.

These are close pairs and require the right conditions to split them
cleanly.

The most important factor is the "seeing"- the stability of the
atmosphere. If
the seeing is not good them these will be difficult to split. Some nights
the
stars are big and round and it is obvious the seeing is bad, the next
night
everything might just be hunky dory and the stars are tight and you can
split
them nicely.

Collimation is important, it could be a problem but I have split the
double
double some pretty miscollimated scopes.

Cool down is the third factor, it the mirror is not cooled down, splitting
the
double-double may be difficult.

Look at Polaris at high magnification, what does it look like, both in and
out
of focus. In focus, is it a tight round point/dot with sharp diffraction
spikes. If so, then you are probably ready for the double-double.

Make sure you are looking at the right pair. I have picked the wrong pair
on
occasion, it does not split well.

jon