Nchịkọta ụyọkọ kpakpando
Usoro Hubble [2] atụmatụ nkewa ọdịdị maka ụyọkọ kpakpando nke Edwin Hubble mepụtara na 1926. [3]A na akpọkarị ya "Hubble tuning fork" n'ihi ọdịdị nke a na anọchite anya ya. Atụmatụ Hubble [4]-ekewa ụyọkọ kpakpando n'ime klas atọ sara mbara dabere na ọdịdị anya ha (nke mbụ na Foto foto): [1]
- Ụyọkọ kpakpando ndị na-agba gburugburu nwere diski dị larịị, na kpakpando na-emepụta (na-abụkarị aka abụọ), na etiti kpakpando a maara dị ka bulge, nke yiri n'ọdịdị ụyọkọ kpakpi elliptical. A na-enye ha akara "S". A na-ahụkwa ihe dị ka ọkara nke ihe niile na-agba gburugburu ka ha nwere ihe dị ka osisi, na-agbasa site na etiti etiti. A na-enye ihe nnọchianya "SB" a na-egbochi mgbochi ndị a.
- [5] kpakpando lenticular (nke a na akpọ S0) nwekwara ụyọkọ kpakpa na egbuke egbuke nke dị n'etiti nke nwere ihe dị ka diski gbara gburugburu mana, n'adịghị ka ụyọkọ ụyọkọkọ kpakpade na agba gburugburu, diski nke ụyọkọ ndị lenticular enweghị ihe a na ahụ anya na agbagharị agbagharị ma ọ naghị arụsi ọrụ ike ịmepụta kpakpando n'ọtụtụ ọ bụla.
Enwere ike ịgbatị klas ndị a sara mbara iji mee ka ọdịiche dị nro nke ọdịdị na iji gụnye ụdị ụyọkọ kpakpando ndị ọzọ, dị ka ụyọkọ ụyọkọ, nke na enweghị ọdịdị doro anya (ma ọ bụ diski ma ọ bụ ellipsoidal). [4]
A na anọchite anya usoro Hubble n'ụdị fork abụọ, na ellipticals n'aka ekpe (na ogo ellipticity na abawanye site n'aka nri) na mgbochi na unbarred spirals na emepụta mgbochi abụọ nke fork n'aka aka nri. [7] na etinye ụyọkọ kpakpando lenticular n'etiti ellipticals na spirals, n'ebe ogwe abụọ ahụ zutere "mkpịsị aka".
[8] taa, usoro Hubble bụ usoro a na ejikarị eme ihe maka ịhazi ụyọkọ kpakpando, ma na nyocha ndị ọkachamara na mbara igwe ma na nkà mmụta mbara igwe. [9][10] o sina dị, na June 2019, ndị ọkà mmụta sayensị obodo site na Galaxy Zoo kọrọ na nhazi Hubble a na ahụkarị, ọkachasị gbasara ụyọkọ kpakpando na agba gburugburu, nwere ike ọ gaghị akwado, ọ pụkwara ịchọ mmelite.
Usoro De Vaucouleurs
[dezie | dezie ebe o si]Usoro de Vaucouleurs maka ịhazi ụyọkọ kpakpando bụ ndọtị a na ejikarị eme ihe na Usoro Hubble, nke Gérard de Vaucouleurs kọwara na 1959. [11] De Vaucouleurs kwuru na nhazi abụọ nke ụyọkọ kpakpando na agba gburugburu nke Hubble - dabere na nkwụsi ike nke ogwe aka na agbagharị agbagharị na ọnụnọ ma ọ bụ enweghị ogwe aka akọwaghị nke ọma ụdị ụyọkọ ụyọkọ. [12], o kwuru na mgbaaka na oghere anya bụ ihe dị mkpa nke ụyọkọ kpakpando na agba gburugburu.
Usoro de Vaucouleurs na ejigide nkewa nke ụyọkọ kpakpando Hubble n'ime elliptical, Lenticulars, spirals na irregular. Iji mezue atụmatụ Hubble, de Vaucouleurs webatara usoro nkewa dị mgbagwoju anya maka ụyọkọ kpakpando na agba gburugburu, dabere na njirimara atọ: [13]
- ↑ A remarkable galactic hybrid. www.spacetelescope.org. Retrieved on 27 February 2017.
- ↑ Hubble (1936). The Realm of the Nebulae. New Haven: Yale University Press.
- ↑ Hubble (1926). "Extra-galactic nebulae". Contributions from the Mount Wilson Observatory / Carnegie Institution of Washington 324: 1–49.
- ↑ 4.0 4.1 The Hubble tuning fork – classification of galaxies (en). www.spacetelescope.org. Archived from the original on 2019-02-09. Retrieved on 2019-02-06.
- ↑ Lenticular Galaxies. cas.sdss.org. Retrieved on 2019-02-06.
- ↑ "Hubble explores the origins of modern galaxies", ESA/Hubble Press Release. Retrieved on 20 August 2013.
- ↑ Galaxies. www.jb.man.ac.uk. Retrieved on 2019-02-06.
- ↑ Iafrate. THE HUBBLE SEQUENCE. uni-heidelberg.de. Retrieved on 2019-02-06.
- ↑ Masters, Karen L. (30 April 2019). "Galaxy Zoo: unwinding the winding problem – observations of spiral bulge prominence and arm pitch angles suggest local spiral galaxies are winding". Monthly Notices of the Royal Astronomical Society 487 (2): 1808–1820. DOI:10.1093/mnras/stz1153. Retrieved on 12 June 2019.
- ↑ Royal Astronomical Society. "Citizen scientists re-tune Hubble's galaxy classification", EurekAlert!, 11 June 2019. Retrieved on 11 June 2019.
- ↑ De Vaucouleurs (1959). "Classification and Morphology of External Galaxies", Astrophysik IV: Sternsysteme / Astrophysics IV: Stellar Systems, Handbuch der Physik / Encyclopedia of Physics, 275–310. DOI:10.1007/978-3-642-45932-0_7. ISBN 978-3-642-45934-4.
- ↑ Binney (1998). Galactic Astronomy. Princeton: Princeton University Press. ISBN 978-0-691-02565-0.
- ↑ Galaxy – Types of galaxies (en). Encyclopedia Britannica. Retrieved on 2019-02-06.
A na ejikọta ihe dị iche iche nke atụmatụ nkewa - an'usoro edepụtara ha - iji nye nhazi zuru ezu nke ụyọkọ kpakpando. Dịka ọmụmaatụ, a na-egosi ụyọkọ kpakpando na agba gburugburu nke na adịghị ike nke nwere ogwe aka na enweghị mgbagwoju anya na mgbaaka SAB (r) c.
N'ile anya, enwere ike ịnọchite anya usoro de Vaucouleurs dị ka ụdị atọ nke fork tuning nke Hubble, yana ọkwa (spiralness) na x-axis, ez (barredness) na y-axis. [1]
Ogologo ọnụọgụ Hubble
[dezie | dezie ebe o si]De Vaucouleurs nyekwara ọnụọgụ ọnụọgụ maka klas ọ bụla nke ụyọkọ kpakpando na atụmatụ ya. Ọnụ ọgụgụ nke ọnụọgụ Hubble T na aga site na -6 ruo +10, na ọnụọgụ ndị na adịghị mma kwekọrọ na ụdị ụyọkọ kpakpando mbụ (ellipticals na lenticulars) na ọnụọụọgụ ndị dị mma na ụdị ndị na adịbeghị anya (spirals na irregulars). [2] Ya mere, dị ka iwu siri ike, ọnụ ọgụgụ dị ala nke T kwekọrọ na akụkụ buru ibu nke kpakpando dị na spheroid / bulge metụtara diski ahụ. Nkọwapụ<[3]B id="mwlg">T dị n'etiti spheroid-to-total stellar mass ratio (MB / MT) na ọkwa Hubble bụ MB / MT = (10 - T) 2 / 256 dabere na ụyọkọ kpakpando mpaghara.
A na ekewa ụyọkọ kpakpando elliptical n'ime 'mpaghara' atọ: ellipticals compact (cE), ellipticels nkịtị (E) na ụdị late (E +). A na-ekewa lenticulars n'otu aka ahụ n'ụdị mmalite (S−), etiti (S0) na nke ikpeazụ (S +). Ụyọkọ kpakpando ndị na adịghị mma nwere ike ịbụ ụdị Magellanic irregular ('T' = 10) ma ọ bụ 'compact' (T = 11).
Ogologo oge T | −6 | −5 | −4 | −3 | −2 | −1 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
de Vaucouleurs klas[1] | cE | E | E+ | S0− | 0 | S0+ | S0/a | Sa | Sab | Sb | Sbc | Sc | Scd | Sd | Sdm | Sm | Im | |
[4] atụ nke klas Hubble [1] | E | S0 | S0/a | Sa | Sa-b | Sb | Sb-c | Sc | Sc-Irr | Irr nke Mbụ |
Ojiji nke ọnụọgụ ọnụọgụ na enye ohere maka ọmụmụ ihe ndị ọzọ gbasara ọdịdị ụyọkọ kpakpando.
Atụmatụ Yerkes (ma ọ bụ Morgan)
[dezie | dezie ebe o si]Ụdị spectral | Nkọwa |
---|---|
a | Kpakpando A A A A Ma Ama |
af | Kpakpando A-F a ma ama |
f | Kpakpando F a ma ama |
fg | Kpakpando F-G a ma ama |
g | Kpakpando G a ma ama |
gk | Kpakpando G-K a ma ama |
k | K kpakpando ndị a ma ama |
Ọdịdị kpakpando | Nkọwa |
---|---|
B | Okirikiri a machibidoro iwu |
D | Nchịkọta ntụgharị na-enweghị usoro na-agba gburugburu ma ọ bụ nke elliptical |
E | Elliptical |
Ep | Elliptical na-amịkọrọ uzuzu |
M | Ihe na-adịghị mma |
L | Ìhè dị ala |
N | Obere nucleus na-egbuke egbuke |
S | Okirikiri |
Mmetụta | Nkọwa |
---|---|
1 | Galaxy bụ "ihu-ihu" |
2 | |
3 | |
4 | |
5 | |
6 | |
7 | Galaxy bụ "n'akụkụ" |
[5] mere, dịka ọmụmaatụ, a na ahazi ụyọkọ Andromeda dị ka kS5.
Hụkwa
[dezie | dezie ebe o si]- Nchịkọta nke ụyọkọ kpakpando - Ndepụta Russia nke ụyọkọ kpakpando 30,642
- Ihe osise ụyọkọ kpakpando - Chọọchị na egosi mmekọrịta dị n'etiti ìhè na ịdị arọ nke nnukwu usoro kpakpando
- Ogige Ntụrụndụ Galaxy - Ọrụ igwe na ahụ maka ihe ndị dị na mbara igwe
- William Wilson Morgan - Onye America na enyocha mbara igwe
- Fritz Zwicky - Onye Switzerland na enyocha mbara igwe (1898-1974)
Ihe odide
[dezie | dezie ebe o si]Njikọ mpụga
[dezie | dezie ebe o si]- ↑ 1.0 1.1 De Vaucouleurs (1994). "Global Physical Parameters of Galaxies" (PostScript). Retrieved on 2008-01-02.
- ↑ Qualitative and Quantitative Classifications of Galaxies. ned.ipac.caltech.edu. Retrieved on 2019-02-06.
- ↑ Obreschkow (2009). "Simulation of the Cosmic Evolution of Atomic and Molecular Hydrogen in Galaxies". The Astrophysical Journal 698 (2). DOI:10.1088/0004-637X/698/2/1467.
- ↑ Binney (1998). Galactic Astronomy. Princeton: Princeton University Press. ISBN 978-0-691-02565-0.
- ↑ Darling. galaxy classification. www.daviddarling.info. Retrieved on 2019-02-06.