Home     Getting Started     To Survive in the Universe    
Inhabited Sky
    News@Sky     Astro Photo     The Collection     Forum     Blog New!     FAQ     Press     Login  

NGC 4025



Upload your image

DSS Images   Other Images

Related articles

Arcsecond Positions of UGC Galaxies
We present accurate B1950 and J2000 positions for all confirmed galaxiesin the Uppsala General Catalog (UGC). The positions were measuredvisually from Digitized Sky Survey images with rms uncertaintiesσ<=[(1.2")2+(θ/100)2]1/2,where θ is the major-axis diameter. We compared each galaxymeasured with the original UGC description to ensure high reliability.The full position list is available in the electronic version only.

Kinematics of the local universe. VII. New 21-cm line measurements of 2112 galaxies
This paper presents 2112 new 21-cm neutral hydrogen line measurementscarried out with the meridian transit Nan\c cay radiotelescope. Amongthese data we give also 213 new radial velocities which complement thoselisted in three previous papers of this series. These new measurements,together with the HI data collected in LEDA, put to 6 700 the number ofgalaxies with 21-cm line width, radial velocity, and apparent diameterin the so-called KLUN sample. Figure 5 and Appendices A and B forcorresponding comments are available in electronic form at thehttp://www.edpsciences.com

Total magnitude, radius, colour indices, colour gradients and photometric type of galaxies
We present a catalogue of aperture photometry of galaxies, in UBVRI,assembled from three different origins: (i) an update of the catalogueof Buta et al. (1995) (ii) published photometric profiles and (iii)aperture photometry performed on CCD images. We explored different setsof growth curves to fit these data: (i) The Sersic law, (ii) The net ofgrowth curves used for the preparation of the RC3 and (iii) A linearinterpolation between the de Vaucouleurs (r(1/4) ) and exponential laws.Finally we adopted the latter solution. Fitting these growth curves, wederive (1) the total magnitude, (2) the effective radius, (3) the colourindices and (4) gradients and (5) the photometric type of 5169 galaxies.The photometric type is defined to statistically match the revisedmorphologic type and parametrizes the shape of the growth curve. It iscoded from -9, for very concentrated galaxies, to +10, for diffusegalaxies. Based in part on observations collected at the Haute-ProvenceObservatory.

Influence of a partial incompleteness of the sample on the determination of the Hubble constant.
This paper presents a study of the Malmquist bias effect in thedetermination of the Hubble constant from the method of "sosies"(look-alike) galaxies. It is shown that a bias appears when a partialincompleteness exists in the sample. A new method, based on the use ofthe completeness curve, is proposed to correct for such a bias. Afterthis correction, the Hubble constant drops of about 20% just because ofthe existence of the partial incompleteness. From the present resultsand on the acceptance of the distance modulus of primary calibrators,the value of the Hubble constant would be: H_0_=~60km/s/Mpc with aninternal statistical error of about 2km/s/Mpc.

An image database. II. Catalogue between δ=-30deg and δ=70deg.
A preliminary list of 68.040 galaxies was built from extraction of35.841 digitized images of the Palomar Sky Survey (Paper I). For eachgalaxy, the basic parameters are obtained: coordinates, diameter, axisratio, total magnitude, position angle. On this preliminary list, weapply severe selection rules to get a catalog of 28.000 galaxies, wellidentified and well documented. For each parameter, a comparison is madewith standard measurements. The accuracy of the raw photometricparameters is quite good despite of the simplicity of the method.Without any local correction, the standard error on the total magnitudeis about 0.5 magnitude up to a total magnitude of B_T_=17. Significantsecondary effects are detected concerning the magnitudes: distance toplate center effect and air-mass effect.

The CfA Redshift Survey: Data for the NGP +36 Zone
We have assembled redshifts for a complete sample of 719 galaxies withm_zw_ <= 15.5 in the declination range 32.5^deg^ <= δ <=38.5^deg^ and right ascension range 8^h^ <= α <= 17^h^. Wehave determined morphological types for all galaxies in the magnitudelimited sample by direct inspection of the POSS-O plates. 576 of theredshifts are measurements from Mount Hopkins, and 405 are newredshifts. We also include new redshifts for 77 fainter galaxies in thesame strip.

The Case Low-Dispersion Northern Sky Survey. XV. A Region in Ursa Major and Canes Venatici
Positions, estimated magnitudes, and finding charts (when necessary) areprovided for 228 blue and/or emission-line galaxies, H II regions ingalaxies, 114 unresolved blue and/or emission-line objects, includingQSO candidates, and 47 known and suspected blue stars in a ~148 deg^2^region in southeastern Ursa Major and western Canes Venatici in theregion 11^h^00^m^ < R.A. < 12^h^30^m^ and +38^deg^ < Decl. <+47^deg^ ( 1950). The objects, whose blue magnitudes are mostly withinthe range 15-18, were identified on low-dispersion objective-prismplates taken with the Burrell Schmidt telescope at Kitt Peak.

Integrated photoelectric magnitudes and color indices of bright galaxies in the Johnson UBV system
The photoelectric total magnitudes and color indices published in theThird Reference Catalogue of Bright Galaxies (RC3) are based on ananalysis of approximately equals 26,000 B, 25,000 B-V, and 17,000 U-Bmultiaperture measurements available up to mid 1987 from nearly 350sources. This paper provides the full details of the analysis andestimates of internal and external errors in the parameters. Thederivation of the parameters is based on techniques described by theVaucouleurs & Corwin (1977) whereby photoelectric multiaperture dataare fitted by mean Hubble-type-dependent curves which describe theintegral of the B-band flux and the typical B-V and U-B integrated colorgradients. A sophisticated analysis of the residuals of thesemeasurements from the curves was made to allow for the random andsystematic errors that effect such data. The result is a homogeneous setof total magnitudes BTA total colors(B-V)T and (U-B)T, and effective colors(B-V)e and (U-B)e for more than 3000 brightgalaxies in RC3.

Observational data for the kinematics of the local universe. I - Radial velocity measurements
The study of the local velocity field requires the use of a very largesample to describe as accurately as possible some prominent features ofthe local kinematics. The problem of collecting a large sample is mademore difficult because of the Malmquist bias which plagues distancedeterminations. The present program aims at determining bias-freedistances for a complete sample in order to study the local velocityfield. The present paper gives 303 preliminary optical and radioredshifts measured for this program at ESO, OHP and NancayObservatories.

Neutral hydrogen observations of galaxies in superclusters
Neutral hydrogen observations of spiral galaxies in the Uppsala GeneralCatalog were made with the 91 m telescope in Green Bank. Results of theH I observations are presented for 309 objects north of declination +38deg in the right ascension range between 10 h and 22 h and for a sampleof 46 objects just south of the equator in the region around R.A.between 0 h and 3 h. Many of these objects are outlying members ofsuperclusters and may be useful in the study of deviations from Hubbleflow on supercluster scales. Velocity widths as measured by fivedifferent algorithms are presented along with a profile quality index.

Arm classifications for spiral galaxies
The spiral arm classes of 762 galaxies are tabulated; 636 galaxies withlow inclinations and radii larger than 1 arcmin were classified on thebasis of their blue images on the Palomar Observatory Sky Survey (POSS),76 SA galaxies in the group catalog of Geller and Huchra were alsoclassified from the POSS, and 253 galaxies in high-resolution atlaseswere classified from their atlas photographs. This spiral armclassification system was previously shown to correlate with thepresence of density waves, and galaxies with such waves were shown tooccur primarily in the densest galactic groups. The present sampleindicates, in addition, that grand design galaxies (i.e., those whichtend to contain prominent density wave modes) are physically larger thanflocculent galaxies (which do not contain such prominent modes) by afactor of about 1.5. A larger group sample confirms the previous resultthat grand design galaxies are preferentially in dense groups.

KISO survey for ultraviolet-excess galaxies. VI.
Not Available

Morphology of spiral galaxies. I - General properties
Red Palomar Sky Survey plates are scanned to characterize a completesample of 605 spiral galaxies north of declination -33 deg havinginclination angle less than 56 deg and blue diameter 2-15 arcmin. Theselection of the data and the reduction and parameter-extractionprocedures are explained, and the data and the results of statisticalanalysis are presented in tables and graphs. Findings reported include alow frequency of occurrence for small inclination angles (suggestingdistortion of outer structures), similar distributions of central diskbrightness for types Sa-Sc but not for types Sd-Sm (where mean valuesare smaller), fewer late-type galaxies with large exponential-disk scalelengths, no galaxies with both high central brightness and large scalelength (indicating a limit on angular momentum in galaxy formation), anda correlation between mean surface brightness and absolute magnitude forlater-type galaxies but not for types Sa-Scd.

Integrated magnitudes and mean colors of DDO dwarf galaxies in the UBV system. II - Distances, luminosities, and H I properties
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1983AJ.....88..764D&db_key=AST

An H i Study of Scd Galaxies
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1975ApJ...198..527S&db_key=AST

Neutral hydrogen observations of DDO dwarf galaxies
All but 2 of the list of 243 David Dunlap Observatory (DDO) dwarf galaxycandidates have been observed in the H I 21-cm line with the NRAO 91 mand 43 m telescopes, and 179 have been detected. Among these, there areobjects which are particularly interesting because of their low surfacebrightness, including some systems which appear to be intrinsicallyreasonably big, and there are others of interest because they areintrinsically the smallest known extragalactic hydrogen-bearing systems.In this latter category are several new candidates for membership in theLocal Group. For all the detected systems, the radio observationsprovide redshifts, neutral hydrogen masses, and a total mass index. Thedistance independent hydrogen mass to luminosity ratio for the truedwarfs in the DDO sample indicates that they are relatively hydrogenrich with respect to large late type galaxies.

Luminosity classifications of dwarf galaxies.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1966AJ.....71..922V&db_key=AST

Submit a new article

Related links

  • - No Links Found -
Submit a new link

Member of following groups:

Observation and Astrometry data

Constellation:Ursa Major
Right ascension:11h59m10.00s
Aparent dimensions:1.738′ × 1.122′

Catalogs and designations:
Proper Names   (Edit)
NGC 2000.0NGC 4025

→ Request more catalogs and designations from VizieR