magnus
super member
Reged: 03/17/04
Posts: 101
Loc: Sweden
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Naked eye observation of Pleiadies neb. is that possible?
/Magnus
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Anonymous
Unregistered
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Hello Magnus,
I have read that it is possible. But you must have EXTREMELY clean optics and a very dark sky. Clean optics prevent light from scattering and the reason for dark skies is obvious. Let us know if you see the nebulosity.
Roger
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tatarjj
scholastic sledgehammer
Reged: 04/20/04
Posts: 905
Loc: Auburn, AL
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I think he meant naked eye-without any sort of optical aid. And no, it's not possible to spot that nebulousity naked eye.
As far as through a telescope though.... it's pretty easy if you have dark skies to see the nebulousity that extends south off of Merope. Beginners need to remember NOT to use a nebula filter on this object.
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John T.
Auburn, AL
25" f/4.2 Dob
18" Obsession #701
4" Stellar Vue Achromat
8X56 Binos
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Erix
Toad Lily
Reged: 12/25/04
Posts: 20448
Loc: Ohio, USA
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Is there a list of recommended filters for the different nebula that anyone has put together?
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Erika
10" LX200 Classic, ETX70-AT, DS Maxscope 60mm, 12" Truss Dob, Orion ED80, WO Binoviewers, 10x50's and 7x50's Binoculars, Rebel XT 350
Having Fun in the Sun!
More solar fun: 2007 July - tracking NOAA10963
Support bacteria. It's the only culture some people have.
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ArizonaScott
Postmaster
Reged: 04/29/04
Posts: 5028
Loc: Phoenix, AZ
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Yep web page
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Scott
10" LX200 Classic, Konus 200, Orion ST80, ETX90 OTA, 60mm Celestron alt-az, Obie 20x80's, Meade 10x50's
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desertstars
Deja moo
Reged: 11/05/03
Posts: 30019
Loc: Tucson, AZ
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I've just barely picked up any nebulosity using the 'newt at a dark site (this past Messier marathon in fact). I wasn't using a filter of any sort. Can't imagine this would be possible with the nakes eye, though.
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Tom W.
SVP8 'She turned me into a 3-legged Newt' EQ
Ralph, the All-Purpose 102mm Refractor
Under the Desert Stars
"If we don't change direction soon, we'll end up where we're going." Professor Irwin Corey
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Starman1
Vendor - Scope City
Reged: 06/24/03
Posts: 10955
Loc: Los Angeles
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I beg to differ with other posters. The nebulosity surrounding the Pleiades IS visible with the naked eye by using averted vision and paying attention to what you see. I always see the extension around Merope as an extension of the brightness into the sky.
I have seen the Merope nebula in a 3" scope at low power (it looks like a comet with the star approximately where the nucleus would be), and it is very easy in a 6" scope--so long as you have dark, clear, skies.
Nebulosity around the other stars is a little harder, though there are multiple sections visible in an 8" scope on any dark night the Pleiades are above the horizon.
Just a note: no filter helps the visibility of this reflection nebula, but dew will mimic the appearance, so make sure your optics are dry.
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Don Pensack
12.5" Truss Dob, 5" Maksutov
Sustaining Lifetime IDA member, TeleVue junkie
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EdZ
Professor EdZ
Reged: 02/15/02
Posts: 12565
Loc: Cumberland, R I , USA42N71.4W
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Hi Don,
Could you just elaborate a bit on what is your dark sky. For me dark sky is mag 5.5 to 5.8. I suspect you are talking about mag 6.5 to 7.0 skies.
I've observed M45 literally hundreds of times just over the last year and a half, as it was the subject if my LM studies. For the first time in my life this past year I once was able to see the Merope nebula. That was with a BT100 binocular telescope and 4mm exit pupils under mag 5.7 skies. In all my years of record keeping I've never seen it with either of my 6" scopes nor my 5" scope. I hold no hope of seeing it naked eye!
edz
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Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
member#21
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BillFerris
Carpal Tunnel
Reged: 07/17/04
Posts: 2582
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Hi Magnus,
The bright reflection nebula around the star Merope (=NGC 1435, "Merope Nebula") in the Pleiades has been sighted many times in small apertures. It was discovered by Wilhelm Tempel in 1859 using a 4-inch refractor and has been seen in handheld binoculars. Other reflection nebulosities have been catalogued near the bright stars Maia, Electra, Alcyone, Celaeno and Taygeta.
Naked eye sightings of the Pleiades' nebulosities are complicated by the fact that as many as a dozen or more stars within the cluster are visible to the naked eye with a host of fainter stars populating the area. In short, it's difficult to know with certainty if you're seeing nebulosity or the faint glow of unresolved stars.
Regards,
Bill in Flagstaff
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Grand Canyon Adventure
Lowering the Threshold
18" Obsession
4.5" Meade 4500
10x50 Swift Audubon
Cosmic Voyage
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Ron B[ee]
Tyro
Reged: 04/27/03
Posts: 4719
Loc: CA
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Quote:
Naked eye observation of Pleiadies neb. is that possible?
/Magnus
I tried several times and finally saw the Merope and Maia nebula one very transparent night with my 4-inch TV-102 Light Cup. I think the key is transparency and any haze or light scatter would just make the observation dubious. I used various stars outside of M45 as gauge to make sure it wasn't light scattering  , a tip I gratefully got from an expert.
Ron B[ee]
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5-inch Tele Vue NP127 APO 
4-inch Tele Vue TV-102 APO 
8-inch f/6 Discovery PDHQ Dob 
Edited by Ron B[ee] (03/21/05 02:33 PM)
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dgs©
Postmaster
Reged: 03/29/04
Posts: 13899
Loc: West Monroe, Louisiana
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I think Bill's explanation of unresolved, fainter stars meshes with what I have seen out of the corner of my eye... even while driving north and the Pleiades were ~60° up in the west. Looking directly at them I only see 5 or 6 stars.
I once thought I was seeing the nebulosity in my 8"Ø. Then I noticed the 'nebulosity' was growing... turned out to be condensation forming on the eyepiece. 
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- david
8"Ø Newtonian on SVP, Moonlite CR2, Telrad
PST Oberwerk Ultra 15x70 Orion Ultraview 10×50
Hand-me-down Sears Refractor (Discoverer) 60mm×900mm
"What we have done for ourselves alone dies with us; what we have done for others and the world, remains and is immortal." --Albert Pike
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Starman1
Vendor - Scope City
Reged: 06/24/03
Posts: 10955
Loc: Los Angeles
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Quote:
Hi Don,
Could you just elaborate a bit on what is your dark sky. For me dark sky is mag 5.5 to 5.8. I suspect you are talking about mag 6.5 to 7.0 skies.
I've observed M45 literally hundreds of times just over the last year and a half, as it was the subject if my LM studies. For the first time in my life this past year I once was able to see the Merope nebula. That was with a BT100 binocular telescope and 4mm exit pupils under mag 5.7 skies. In all my years of record keeping I've never seen it with either of my 6" scopes nor my 5" scope. I hold no hope of seeing it naked eye!
edz
Ed,
My dark sky is typically 6.5 to 6.8 as you suggest.
I know I have seen the nebula with the naked eye and not just the faint haze of unresolved dimmer stars because I see the Merope nebula as an streaky extension of the glow, moving away from the star at exactly the correct position angle. My view of the Pleiades, naked eye, and averted, is over 2 degrees wide, comparing with the size of the North America nebula, which is also naked eye at the site where I observe.
At 54, I can still count around 9-10 stars in the Pleiades most nights, and up to 12 if I take steps to exclude peripheral light from my vision (a couple of the visible stars are not immediately adjacent to the "dipper" shape). I can also see epsilon Lyrae as a naked-eye double star, too. [I'm slightly farsighted, but have zero astigmatism].
There is a distinct advantage to being at high altitude, too. The lack of atmospheric aerosols increases the transparency a lot, so nebulosity and faint galaxy details are visible in smaller apertures than you would expect.
The naked eye limit is usually deeper in the Western part of the sky where I observe--it is interesting to see the "Dark Horse" (the Pipe nebula is part) become more visible as the Milky Way shifts west of the meridian. Seeing is always better in the West, as well. We have discussed this and think it is due to the nature of the air flow over the site, coupled with the absence of towns and cities in that direction.
M13, though visible naked eye shortly after it rises, becomes a Telrad target when it is west of the meridian. Normally, it is hard to use a Telrad on a 5th magnitude star because of the brightness of the bullseye.
We had one young man draw a picture of the Milky Way's bulge all the way out to alpha and beta Librae one night, so younger eyes than mine just might be able to see more of the Pleiades.
What is the largest number of stars in the Pleiades ever seen naked eye?
That would be fascinating to know.
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Don Pensack
12.5" Truss Dob, 5" Maksutov
Sustaining Lifetime IDA member, TeleVue junkie
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ArizonaScott
Postmaster
Reged: 04/29/04
Posts: 5028
Loc: Phoenix, AZ
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I'm pretty sure that subject is discussed in Deep Sky Wonders. Anybody got a copy handy that can give us a quick report?
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Scott
10" LX200 Classic, Konus 200, Orion ST80, ETX90 OTA, 60mm Celestron alt-az, Obie 20x80's, Meade 10x50's
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Starman1
Vendor - Scope City
Reged: 06/24/03
Posts: 10955
Loc: Los Angeles
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Quote:
I'm pretty sure that subject is discussed in Deep Sky Wonders. Anybody got a copy handy that can give us a quick report?
Scotty said 18, with 30 within reach of mag.7.5 skies, though he says the brighter stars make sighting the fainter ones hard, if not impossible.
Leslie Peltier said he always saw 12 to 14 on every clear moonless night.
10 of the stars have names, so many observers must be able to see 10.
Scotty also reports other observers reporting naked-eye sightings of the nebula.
Nothing special about my skies, I guess.
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Don Pensack
12.5" Truss Dob, 5" Maksutov
Sustaining Lifetime IDA member, TeleVue junkie
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ArizonaScott
Postmaster
Reged: 04/29/04
Posts: 5028
Loc: Phoenix, AZ
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Thanks for checking Don. I can normally see 6 from my pretty poor skies. I've tried to detect the nebulosity from a dark site with a UHC filter held up to my eye, but believe that all I'm seeing is the glow from unresolved stars.
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Scott
10" LX200 Classic, Konus 200, Orion ST80, ETX90 OTA, 60mm Celestron alt-az, Obie 20x80's, Meade 10x50's
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EdZ
Professor EdZ
Reged: 02/15/02
Posts: 12565
Loc: Cumberland, R I , USA42N71.4W
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Well, even in my mag 5.7-5.8 skies, I've counted 10 stars naked eye in M45. 18Tau is seen, but 21,22Tau is seen as one. I also see M13 unaided on occasion. And I have seen e1 e2 Lyra separated Naked Eye, but thta's a measure of visual acuity, not contrast perception, seeing the faint light of an extended object.
edz
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Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
member#21
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Starman1
Vendor - Scope City
Reged: 06/24/03
Posts: 10955
Loc: Los Angeles
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Scott,
Since this is a full-spectrum reflection nebula, a UHC filter would dim it to near invisibility. Unfortunately, the best way to view it is without any filter.
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Don Pensack
12.5" Truss Dob, 5" Maksutov
Sustaining Lifetime IDA member, TeleVue junkie
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ArizonaScott
Postmaster
Reged: 04/29/04
Posts: 5028
Loc: Phoenix, AZ
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Gotcha. Thanks Don 
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Scott
10" LX200 Classic, Konus 200, Orion ST80, ETX90 OTA, 60mm Celestron alt-az, Obie 20x80's, Meade 10x50's
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Erix
Toad Lily
Reged: 12/25/04
Posts: 20448
Loc: Ohio, USA
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Quote:
Yep web page
Thank you, Scott. 
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Erika
10" LX200 Classic, ETX70-AT, DS Maxscope 60mm, 12" Truss Dob, Orion ED80, WO Binoviewers, 10x50's and 7x50's Binoculars, Rebel XT 350
Having Fun in the Sun!
More solar fun: 2007 July - tracking NOAA10963
Support bacteria. It's the only culture some people have.
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Scott Beith
SRF
Reged: 11/26/03
Posts: 33042
Loc: Gulfport, MS
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I get 7 stars naked eye from my brutally light polluted front yard. That is looking directly over streetlights. I have never checked from a dark sky.
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  Scott
"The only thing necessary for the triumph of evil is for good men to do nothing." -- Edmund Burke.
"People sleep peaceably in their beds at night only because rough men stand ready to do violence on their behalf." -- George Orwell
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