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We present near-infrared (NIR) spectroscopic observations of the blue compact dwarf (BCD) galaxy Mrk 59, obtained with the TripleSpec spectrograph mounted on the 3.5m APO telescope. The NIR spectrum of Mrk 59, which covers the 0.90 µm -2.40 µm wavelength range, shows atomic hydrogen, molecular hydrogen, helium, sulfur and iron emission lines. The NIR data have been supplemented by a SDSS optical spectrum. We found extinction in the BCD to be low [A(V )=0.24 mag] and to be the same in both the optical and NIR ranges. The NIR light does not reveal hidden star formation. The H 2 emission comes from dense clumps and the H 2 vibrational emission line intensities can be accounted for by photon excitation. No shock excitation is needed. A CLOUDY photoinization model of Mrk 59 reproduces well the observed optical and NIR emission line fluxes. There is no need to invoke sources of ionization other than stellar radiation. The [Fe ii] 1.257 and 1.643 µm emission lines, often used as supernova shock indicators in low-excitation high-metallicity starburst galaxies, cannot play such a role in high-excitation low-metallicity H ii regions such as Mrk 59.

We report 0.8-2.5 m spectrophotometry of CI Aquilae at eight epochs between 2000 May 9 and 2001 June 2 UT, corresponding to approximately 3 and 391 days after peak brightness. Near peak brightness, the spectra showed emission lines that were characteristic of a low-excitation, nitrogen-rich shell. Within a few weeks, the spectra began to show higher excitation/ionization emission lines indicative of a harder illuminating source: the neutral metal lines faded, leaving only lines of H i, He i, and He ii and the emerging coronal lines. A month after peak brightness, the [Ca viii] coronal line at 2.3205 m appeared and persisted until the last of our observations, on day +391. From the O i line ratios, we deduced a reddening of E BÀV = 1.5 AE 0.1 and a visual extinction of A V = 4.6 AE 0.2. Along with the rate of decline from the light curve (t 2 ), we derived a distance of 2.6 AE 1.3 kpc. The frequently observed unidentified novae lines were present in CI Aquilae along with a potentially new member of the group at 2.425 AE 0.002 m.

In equation (2), we incorrectly labeled one of the variables. Equations (1) and (2) should read:These equations were used only to explain our image frame-tie method, and this change does not affect our results.

We present medium-resolution (R ∼ 600), mid-infrared (7.5-14 µm) spectra of 15 young planetary nebulae. Linestrengths for observed forbidden transitions are presented, and numerous broad emission features from silicates, polyaromatic hydrocarbons (PAHs) and silicon carbide (SiC) are observed.