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Type: reflection nebula
Mag: B=?, V=?
Size: ?
PA: ?
NGC 1554 and NGC 1555 are both involved with the young variable star T Tauri. They are among the most notorious of the nebulae found during the 19th century as they are the only nebulae certainly known to vary in brightness -- even to the point of disappearing, as NGC 1554 has done. They are most likely reflection nebulae, created as thick dust clouds near the star move about, mostly casting shadows, but occasionally letting "shafts of sunlight" out to illuminate the surrounding dense interstellar gas and dust.
Nebulae were first noticed around the star by Hind in the 1850's, and were later observed by d'Arrest, Struve, and Dreyer among others. Dreyer has brief synopses of the observations in the NGC and IC Notes, and points (in the IC2 Notes) to a paper by Barnard in Monthly Notices which details most of the history of the T Tauri nebulae up to about 1900.
For all the fuss that these nebulae created in the 19th century, they are all quite small and very faint at the present time. As I noted above, NGC 1554 is not visible on the Palomar Sky Survey plates (taken in the early 1950's). Also not visible is a nebula seen only by Bigourdan (B. 144; mislabeled as B. 143 by him in his big table). He makes its position 04 19 09.5, +19 21 51 (B1950.0) from a single observation on 12 Dec 1890. This is about 4 arcmin southeast of T Tauri in a blank patch of sky.
Still, observers might find it fascinating to monitor the area for changes.
This object lies four seconds west of NGC 1555, Hind's Nebula. Dreyer notes that it is a small nebula with an eccentric nucleus equal to a 14th magnitude star. It was discovered early in 1868 by Otto Struve, and was also observed by d'Arrest, who was sure that no nebulosity had formerly existed in that place. Dreyer adds: "this object must also have disappeared since, as I was unable to perceive any nebulosity near the place with Lord Rosse's 6-foot Reflector in 1877. The place has also been examined of late years by Tempel [using an 11-inch refractor] with similar result."
Ced 32a (NGC 1554)
Position (1900): RA 4 15.9, Dec + 19 17
Star: 19 706? (variable Mp and V, SpT=Gpe)
Spectrum of nebula: continuous spectrum (inferred from sp.t. of illuminating star)
Classification: Neb associated with mainly one star (which may be multiple) - Fan-shaped object (eg. IC 59)
Size: variable
Notes: "The nebulous region around T Tauri, a = NGC 1554 = GC 5339 = Struve's lost nebula. Disc. O. Struve 1868. Compare (59). b = NGC 1555 = GC 839 = Hind's variable nebula. Comprehending discussion: (59). (63, 75, 92, 114, 124, 152, 153, 156, 212, 216, 406, 460, 486, 491, 548, 550, 578, 600, 631, 746). Disc. Hind 1852. C = T Tauri nebulous. Disc. Burnham 1890 (152). (1, 59, 216)."
Bernes, C. (1977) A catalogue of bright nebulosities in opaque dust clouds.
NGC 1554/NGC 1555 =Bernes 84
(Sulentic and Tifft 1973) notes that this is a diffuse nebula.
Lynds, B.T. (1962) Catalogue of dark nebulae. Astrophys.J.Suppl.Ser. 7, 1-52. [also: computer datafile: VII/7A]
Hind's variable nebula & Struve's Lost nebula
04 21.8 +19 32
17.5: this refers to Hind's variable nebula, illuminated by T Tauri (9-13). At 100x and 140x (unfiltered) an extremely faint haze was highly suspected on the W or WSW side of T Tauri (mag 9) in the direction of a mag 14 star to the W (or slightly south). Not seen at 220x. No details visible (did not appear as an arc) but the sketch made at 100x exactly matches the orientation of the nebulosity with respect to T Tauri. No nebulosity noted on the E side of the star.
Telescope: Meade 8"
Eyepiece - 25mm, 18mm wide angle, 15mm.
Date: 14 February 1999
Nebula, Taurus, 4h 21m 8s, +19 32
Appears as a soft glow in the eyepiece field, just visible to the north-east (and including) the star T Tauri. The field is shared by a bright star a few arcminutes to the west, and two pairs further off to the north and south.
NGC: 1554 - Taurus
Nebula
Tel: 12" S/C – 218x – 346x - Date: 31 Jan 2008 – Site: Alldays - good
I estimate this star now at more or less 10.5 to 10.7 in magnitude. The haze towards the NW of 9.8 TTarui is easy seen although no definition 218x.
Lacaille's catalogue
The Messier objects
Dunlop's catalogue
The Bennett objects
The Caldwell list
Named DSOs
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