Pisces Overdensity

{{Short description|Clump of stars within the halo of the Milky Way}}

{{Infobox Galaxy

| image =

| caption =

| name = Pisces Overdensity

| epoch = J2000

| type = dIrr/dSph

| ra = {{RA|23|19|00}}

| dec = {{DEC|+00|00|00}}

| dist_ly = {{cvt|260|kly|kpc|lk=on}}

| z =

| absmag_v = −10.35

| size_v = ~1°

| constellation name = Pisces

| names = Pisces Plume

}}

The Pisces Overdensity is a clump of stars in the Milky Way's halo, which may be a disrupted dwarf spheroidal galaxy. It is situated in the Pisces constellation and was discovered in 2009 by analysis of distribution of RR Lyrae stars in the data obtained by the Sloan Digital Sky Survey's data. The galaxy is located at the distance of about 80 kpc from the Sun and moves towards it with a speed of about 75 km/s.

The Pisces Overdensity is one of the faintest satellites of the Milky Way. Its mass is estimated to be at least 10⁵ Solar masses. However it has a large size of about several degrees (around 1 kpc) and may be in a transitional phase between a gravitationally bound galaxy and completely unbound system. The Pisces Overdensity is located near the plane, where the Magellanic Clouds lie. There may exist a connection between the Magellanic Stream and this galaxy.

References

{{reflist|refs=

{{citation | display-authors=1 | last1=Belokurov | first1=V. | last2=Walker | first2=M. G. | last3=Evans | first3=N. W. | last4=Gilmore | first4=G. | last5=Irwin | first5=M. J. | last6=Just | first6=D. | last7=Koposov | first7=S. | last8=Mateo | first8=M. | last9=Olszewski | first9=E. | last10=Watkins | first10=L. | last11=Wyrzykowski | first11=L. | title=Big fish, small fish: Two New Ultra-Faint Satellites of the Milky Way | date=2010 | journal=The Astrophysical Journal Letters | volume=712 | issue=1 | pages=L103–106 | bibcode=2010ApJ...712L.103B | doi=10.1088/2041-8205/712/1/L103 | arxiv=1002.0504 | s2cid=29195107 | postscript=. }}

{{citation | display-authors=1 | last1=Watkins | first1=L. L. | last2=Evans | first2=N. W. | last3=Belokurov | first3=V. | last4=Smith | first4=M. C. | last5=Hewett | first5=P. C. | last6=Bramich | first6=D. M. | last7=Gilmore | first7=G. F. | last8=Irwin | first8=M. J. | last9=Vidrih | first9=S. | last10=Wyrzykowski | first10=Ł. | last11=Zucker | first11=D. B. | title=Substructure revealed by RR Lyraes in SDSS Stripe 82 | date=2009 | journal=Monthly Notices of the Royal Astronomical Society | volume=398 | issue=4 | pages=1757–70 | doi=10.1111/j.1365-2966.2009.15242.x | doi-access=free | bibcode=2009MNRAS.398.1757W | arxiv=0906.0498 | s2cid=14409027 | postscript=. }}

{{citation | display-authors=1

| last1=Kollmeier | first1=Juna A. | last2=Gould | first2=Andrew | last3=Shectman | first3=Stephen | last4=Thompson | first4=Ian B. | last5=Preston | first5=George W. | last6=Simon | first6=Joshua D. | last7=Crane | first7=Jeffrey D. | last8=Ivezić | first8=Željko | last9=Sesar | first9=Branimir | title=Spectroscopic Confirmation of the Pisces Overdensity | date=2009 | journal=The Astrophysical Journal Letters | volume=705 | issue=2 | pages=L158–L162 | arxiv=0908.1381 | bibcode=2009ApJ...705L.158K | doi=10.1088/0004-637X/705/2/L158 | s2cid=9825846 | postscript=. }}

{{cite journal | bibcode=2009ApJ...697.1993B | doi=10.1088/0004-637X/697/2/1993 | arxiv=0903.3871 | title=Aspitzerstudy of Asymptotic Giant Branch Stars. Iii. Dust Production and Gas Return in Local Group Dwarf Irregular Galaxies | journal=The Astrophysical Journal | volume=697 | issue=2 | pages=1993 | year=2009 | last1=Boyer | first1=Martha L | last2=Skillman | first2=Evan D | last3=Van Loon | first3=Jacco Th | last4=Gehrz | first4=Robert D | last5=Woodward | first5=Charles E | s2cid=12162514 }}

}}

Category:Local Group

Category:Dwarf spheroidal galaxies

Category:Pisces (constellation)

Category:Milky Way Subgroup