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We present new narrow-band Hα, [N II], and [O III] high-resolution images of the quadrupolar planetary nebula (PN) NGC 6309 that show in great detail its bipolar lobes and reveal new morphological features. New high-and low-dispersion long-slit spectra have been obtained to help in the investigation of the new nebular components. The images and spectra unveil two diffuse blobs, one of them located ≃ 55 ′′ from the central star along the NE direction (PA=+71 • ) and the other at ≃ 78 ′′ in the SW direction (PA=-151 • ). Therefore, these structures do not share the symmetry axes of the inner bipolar outflows. Their radial velocities relative to the system are quite low: +3 and -4 km s −1 , respectively. Spectroscopic data confirm a high [O III] to Hβ ratio, indicating that the blobs are being excited by the UV flux from the central star. Our images convincingly show a spherical halo 60 ′′ in diameter encircling the quadrupolar nebula. The expansion velocity of this shell is low, 6 km s −1 . To study the formation history of NGC 6309, we have used our new images and spectra, as well as available echelle spectra of the innermost regions, to estimate the kinematical age of each structural component: the software SHAPE has been used to construct a morpho-kinematic model for the ring and the bipolar flows that implies an age of ∼4,000 yrs, the expansion of the halo sets a lower limit for its age 46,000 yrs, and the very low expansion of the blobs suggests they are part of a large structure corresponding to a mass ejection that took place ∼150,000 yrs ago. In NGC 6309 we have direct evidence of a change in the geometry of mass-loss, from spherical in the halo to axially-symmetric in the two pairs of bipolar lobes.

Nonassociative geometry, providing a unified description of discrete and continuum spaces, is a valuable candidate for the study of discrete models of spacetime. Within the framework of nonassociative geometry we propose a model of emergent spacetime. In our approach, the evolution of spacetime geometry is governed by a random/stochastic process. This leads to a natural appearance of causal structure and arrow of time. We apply our approach to study a toy model of discrete (2+1)-D spacetime and Friedmann-Robertson-Walker cosmological model. We show that in a continuous limit the evolution of the discrete spacetime corresponds to a radiation epoch of the standard cosmological model.

The Oil and Gas industry is always looking for methods that reduce costs associated with the drilling process and, over the last decade, eliminate the environmental impact of well preparation. One new technology provides an option for oil and gas producers to achieve that goal allowing installation of two sets of electrical submersible pumps (ESP) on the same well bore but producing two sands separated by a packer. The purpose of the following paper is to to present a real example of the successful installation of a Dual Concentric Completion System in COPA ASUR3, allowing two ESP systems to produce two different sands on the same well bore separated by a packer, and to demonstrate the economic effects of its use, reducing by 38% the costs associated with the drilling process, 14% on the total drill/completion investment and 50% on the environmental impact in COPA field (Colombia). The design and installation of the system were carried out taking into consideration Local Governmental regulations requiring both production zones remain insulated from each other. Evidence explained on this paper helps to conclude that Dual Concentric Systems are proven to be applicable for specific fields with adequate sand distribution and fluid characteristics, also the use of Dual Concentric Systems complies with Government regulations keeping production from both zones isolated when applying the right integrity test procedure and that the use of Dual Concentric Systems significantly reduces costs and environmental impact associated with the drilling process and surface facilities configuration requirements.

We present Spitzer Space Telescope archival mid-infrared (mid-IR) spectroscopy of a sample of eleven planetary nebulae (PNe). The observations, acquired with the Spitzer Infrared Spectrograph (IRS), cover the spectral range 5.2-14.5 μm that includes the H2 0-0 S(2) to S(7) rotational emission lines. This wavelength coverage has allowed us to derive the Boltzmann distribution and calculate the H2 rotational excitation temperature (Tex). The derived excitation temperatures have consistent values ≃ 900 ±70 K for different sources despite their different structural components. We also report the detection of mid-IR ionic lines of [Ar iii], [S iv], and [Ne ii] in most objects, and polycyclic aromatic hydrocarbon (PAH) features in a few cases.