Open main menu
Home
Random
Recent changes
Special pages
Community portal
Preferences
About Wikipedia
Disclaimers
Incubator escapee wiki
Search
User menu
Talk
Dark mode
Contributions
Create account
Log in
Editing
Extinction (astronomy)
(section)
Warning:
You are not logged in. Your IP address will be publicly visible if you make any edits. If you
log in
or
create an account
, your edits will be attributed to your username, along with other benefits.
Anti-spam check. Do
not
fill this in!
==Extinction curves of other galaxies== [[File:Interstellar extinction ave curves local group.png|thumb|right|Plot showing the average extinction curves for the MW, LMC2, LMC, and SMC Bar.<ref name="mw_lmc_smc_comp" /> The curves are plotted versus 1/wavelength to emphasize the UV.]] The form of the standard extinction curve depends on the composition of the ISM, which varies from galaxy to galaxy. In the [[Local Group]], the best-determined extinction curves are those of the Milky Way, the [[Small Magellanic Cloud]] (SMC) and the [[Large Magellanic Cloud]] (LMC). In the LMC, there is significant variation in the characteristics of the ultraviolet extinction with a weaker 2175 Γ bump and stronger far-UV extinction in the region associated with the LMC2 supershell (near the 30 Doradus starbursting region) than seen elsewhere in the LMC and in the Milky Way.<ref>{{Cite journal | last = Fitzpatrick | first = Edward L. | author-link = Edward L. Fitzpatrick | title = An average interstellar extinction curve for the Large Magellanic Cloud | journal = Astronomical Journal | date = 1986 | volume = 92 | pages = 1068β1073 | bibcode = 1986AJ.....92.1068F | doi = 10.1086/114237 | doi-access = free }}</ref><ref>{{Cite journal | last = Misselt | first = Karl A. | author-link = Karl A. Misselt | author2 = Geoffrey C. Clayton | author3-link = Karl D. Gordon | author3 = Karl D. Gordon | title = A Reanalysis of the Ultraviolet Extinction from Interstellar Dust in the Large Magellanic Cloud | journal = Astrophysical Journal | date = 1999 | volume = 515 | issue = 1 | pages = 128β139 | bibcode = 1999ApJ...515..128M | doi = 10.1086/307010 | arxiv = astro-ph/9811036 | s2cid = 14175478 | author2-link = Geoffrey C. Clayton }}</ref> In the SMC, more extreme variation is seen with no 2175 Γ bump and very strong far-UV extinction in the star forming Bar and fairly normal ultraviolet extinction seen in the more quiescent Wing.<ref>{{Cite journal | last1 = Lequeux | first1 = J. | author-link = J. Lequeux | last2 = Maurice | first2 = E. | author-link2 = E. Maurice | last3 = Prevot-Burnichon | first3 = M. L. | author-link3 = M. L. Prevot-Burnichon | last4 = Prevot | first4 = L. | author-link4 = L. Prevot | last5 = Rocca-Volmerange | first5 = B. | author-link5 = B. Rocca-Volmerange | title = SK 143 - an SMC star with a galactic-type ultraviolet interstellar extinction | journal = Astronomy and Astrophysics | date = 1982 | volume = 113 | pages = L15βL17 | bibcode = 1982A&A...113L..15L }}</ref><ref>{{Cite journal | last1 = Prevot | first1 = M. L. | author-link = M. L. Prevot | last2 = Lequeux | first2 = J. | author-link2 = J. Lequex | last3 = Prevot | first3 = L. | author-link3 = L. Prevot | last4 = Maurice | first4 = E. | author-link4 = E. Maurice | last5 = Rocca-Volmerange | first5 = B. | author-link5 = B. Rocca-Volmerange | title = The typical interstellar extinction in the Small Magellanic Cloud | journal = Astronomy and Astrophysics | date = 1984 | volume = 132 | pages = 389β392 | bibcode = 1984A&A...132..389P }}</ref><ref>{{Cite journal | last = Gordon | first = Karl D. | author-link = Karl D. Gordon | author2 = Geoffrey C. Clayton | title = Starburst-like Dust Extinction in the Small Magellanic Cloud | journal = Astrophysical Journal | date = 1998 | volume = 500 | issue = 2 | pages = 816β824 | bibcode = 1998ApJ...500..816G | doi = 10.1086/305774 | arxiv = astro-ph/9802003 | s2cid = 18090417 | author2-link = Geoffrey C. Clayton }}</ref> This gives clues as to the composition of the ISM in the various galaxies. Previously, the different average extinction curves in the Milky Way, LMC, and SMC were thought to be the result of the different [[metallicity|metallicities]] of the three galaxies: the LMC's metallicity is about 40% of that of the [[Milky Way]], while the SMC's is about 10%. Finding extinction curves in both the LMC and SMC which are similar to those found in the Milky Way<ref name="mw_lmc_smc_comp">{{Cite journal | last = Gordon | first = Karl D. | author-link = Karl D. Gordon | author2 = Geoffrey C. Clayton | author3-link = Karl A. Misselt | author3 = Karl A. Misselt | author4-link = Arlo U. Landolt | author4 = Arlo U. Landolt | author5-link = Michael J. Wolff | author5 = Michael J. Wolff | title = A Quantitative Comparison of the Small Magellanic Cloud, Large Magellanic Cloud, and Milky Way Ultraviolet to Near-Infrared Extinction Curves | journal = Astrophysical Journal | date = 2003 | volume = 594 | issue = 1 | pages = 279β293 | bibcode = 2003ApJ...594..279G | doi = 10.1086/376774 | arxiv = astro-ph/0305257 | s2cid = 117180437 | author2-link = Geoffrey C. Clayton }}</ref> and finding extinction curves in the Milky Way that look more like those found in the LMC2 supershell of the LMC<ref>{{Cite journal | last = Clayton | first = Geoffrey C. | author-link = Geoffrey C. Clayton | author2 = Karl D. Gordon | author3-link = Michael J. Wolff | author3 = Michael J. Wolff | title = Magellanic Cloud-Type Interstellar Dust along Low-Density Sight Lines in the Galaxy | journal = Astrophysical Journal Supplement Series | date = 2000 | volume = 129 | issue = 1 | pages = 147β157 | bibcode = 2000ApJS..129..147C | doi = 10.1086/313419 | arxiv = astro-ph/0003285 | s2cid = 11205416 | author2-link = Karl D. Gordon }}</ref> and in the SMC Bar<ref>{{Cite journal | last = Valencic | first = Lynne A. | author-link = Lynne A. Valencic | author2 = Geoffrey C. Clayton | author3-link = Karl D. Gordon | author3 = Karl D. Gordon | author4-link = Tracy L. Smith | author4 = Tracy L. Smith | title = Small Magellanic Cloud-Type Interstellar Dust in the Milky Way | journal = Astrophysical Journal | date = 2003 | volume = 598 | issue = 1 | pages = 369β374 | bibcode = 2003ApJ...598..369V | doi = 10.1086/378802 | arxiv = astro-ph/0308060 | s2cid = 123435053 | author2-link = Geoffrey C. Clayton }}</ref> has given rise to a new interpretation. The variations in the curves seen in the Magellanic Clouds and Milky Way may instead be caused by processing of the dust grains by nearby star formation. This interpretation is supported by work in starburst galaxies (which are undergoing intense star formation episodes) which shows that their dust lacks the 2175 Γ bump.<ref>{{Cite journal | last = Calzetti | first = Daniela | author-link = Daniela Calzetti | author2 = Anne L. Kinney | author3-link = Thaisa Storchi-Bergmann | author3 = Thaisa Storchi-Bergmann | title = Dust extinction of the stellar continua in starburst galaxies: The ultraviolet and optical extinction law | journal = Astrophysical Journal | date = 1994 | volume = 429 | pages = 582β601 | bibcode = 1994ApJ...429..582C | doi = 10.1086/174346 | author2-link = Anne L. Kinney | hdl = 10183/108843 | hdl-access = free }}</ref><ref>{{Cite journal | last = Gordon | first = Karl D. | author-link = Karl D. Gordon | author2 = Daniela Calzetti | author3-link = Adolf N. Witt | author3 = Adolf N. Witt | title = Dust in Starburst Galaxies | journal = Astrophysical Journal | date = 1997 | volume = 487 | issue = 2 | pages = 625β635 | bibcode = 1997ApJ...487..625G | doi = 10.1086/304654 | arxiv = astro-ph/9705043 | s2cid = 2055629 | author2-link = Daniela Calzetti }}</ref>
Edit summary
(Briefly describe your changes)
By publishing changes, you agree to the
Terms of Use
, and you irrevocably agree to release your contribution under the
CC BY-SA 4.0 License
and the
GFDL
. You agree that a hyperlink or URL is sufficient attribution under the Creative Commons license.
Cancel
Editing help
(opens in new window)