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We report optical observations of the Luminous Blue Variable (LBV) HR Carinae which show that the star has reached a visual minimum phase in 2009. More importantly, we detected absorptions due to Si IV λλ4088-4116. To match their observed line profiles from 2009 May, a high rotational velocity of v rot ≃ 150 ± 20 km s −1 is needed (assuming an inclination angle of 30 • ), implying that HR Car rotates at ≃ 0.88 ± 0.2 of its critical velocity for break-up (v crit ). Our results suggest that fast rotation is typical in all strong-variable, bona-fide galactic LBVs, which present S Dor-type variability. Strong-variable LBVs are located in a well-defined region of the HR diagram during visual minimum (the "LBV minimum instability strip"). We suggest this region corresponds to where v crit is reached. To the left of this strip, a forbidden zone with v rot /v crit > 1 is present, explaining why no LBVs are detected in this zone. Since dormant/ex LBVs like P Cygni and HD 168625 have low v rot , we propose that LBVs can be separated in two groups: fast-rotating, strong-variable stars showing S-Dor cycles (such as AG Car and HR Car) and slow-rotating stars with much less variability (such as P Cygni and HD 168625). We speculate that SN progenitors which had S-Dor cycles before exploding (such as in SN 2001ig, SN 2003bg, and SN 2005gj) could have been fast rotators. We suggest that the potential difficulty of fast-rotating Galactic LBVs to lose angular momentum is an additional evidence that such stars could explode during the LBV phase. Electronic address: jgroh@mpifr-bonn.mpg.de 1 Based on observations made with the 1.6-m telescope at the Observatório Pico dos Dias (OPD-LNA, Brazil), with the 2.15m telescope of the Complejo Astronomico El Leoncito (CASLEO, Argentina), and with the 2.2-m ESO telescope at La Silla (Chile) under program 083.D-0589. CASLEO is operated under agreement between CONICET, SECYT, and the National Universities of La

The periodic spectroscopic events in η Carinae are now well established and occur near the periastron passage of two massive stars in a very eccentric orbit. Several mechanisms have been proposed to explain the variations of different spectral features, such as an eclipse by the wind-wind collision boundary, a shell ejection from the primary star or accretion of its wind onto the secondary. All

In this paper we present radial velocity measurements &probable members of Trumpler 14, a very young open cluster associated with the Carina Nebula. We have found 4 double-line spectroscopic binaries and 2 single-line spectroscopic binaries. We have succeeded in deriving orbital elements for the SBIs. All the binaries are of potential astrophysical interest and are worth further observational efforts.