NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-02-18 T06:45:02 PST
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Notes for object NGC 0588

1 note(s) found in NED.


1. 2003ApJS..146....1W
Re:NGC 0588
NGC 588.-The LiF1A and LiF2B spectra appear to show some differences.
However, the differences lie within the noise.
This object is an H II region in M33. The spectrum is therefore an
amalgam of the radiation from many O stars. However, the region near
O VI {lambda}1031.926 looks fairly clean-it is probably dominated by the
hottest and brightest stars. Absorption at Milky Way velocities is very
weak-the 3 {sigma} upper limit is 110 m{angstrom} [log N(O VI) < 14.07].
This is consistent with the weak Milky Way lines seen in the nearby sight
lines to Mrk 352 (7.1deg away), Mrk 357 (7.8deg away) and PG 0052+251
(9.8deg away). The high negative velocity O VI components are also seen
toward those sight lines. The LSR velocity of the H I M33 at the position
of NGC 588 is -220 km s^-1^ (Deul & van der Hulst 1987), but the
O I {lambda}1039.230, Ar I {lambda}1048.220, and Si II {lambda}1020.699
absorption lines are centered at - 180 km s^-1^, while the
C II {lambda}1036.337 absorption extends to -230 km s^-1^.
A priori, one might favor an interpretation in which the O VI components
at -370 (W = 122 +- 27 +- 18 m{angstrom}) and especially the one at
-210 km s^-1^ (W = 301 +- 31 +- 25 m{angstrom}) are associated with M33.
However, similar components are seen toward Mrk 352 (at -295 and
-180 km s^-1^, 147 = 103 and 123 m{angstrom}), toward Mrk 357 (at -280
and -185 km s^-1^, 14" = 131 and 80 m{angstrom}), and toward PG 0052+251
(at -335 and -195 km s^-1^, W = 153 and 77 m{angstrom}), as well as
toward all other sight lines in this part of the sky. Comparing these,
it is clear that the -370 km s^-1^ component toward NGC 588 has an
equivalent width that is similar to that of the other very high
negative velocity components. The -210 km s^-1^ component, however,
is much stronger, and this component is probably dominated by
absorption associated with M33. It is not possible, however, to
disentangle the relative contributions from M33 and the more extended
high negative velocity O VI.


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