Advances in Astrophysics

Number 3, 2019

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The Computational Cosmic Brain

Authors: Idan Ginsburg, Manasvi Lingam, Merrill Butler III

Abstract

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The cosmic web exhibits some striking similarities to that of an animal brain. Despite its tremendous size the cosmos is many orders of magnitude less efficient at computation than the brains residing in Earth’s biosphere. This shows just how information-rich life truly is.

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Ouamuamua (A/2017U1), Panspermia, and Intelligent Life in the Universe

Authors: N.C. Wickramasinghe, D.T. Wickramasinghe, E.J. Steele

Abstract

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We examine a range of arguments relating to the existence of extraterrestrial life and the possible distribution of intelligent life in the galaxy. It has recently been reported that the object (Ouamuamua (A/2017U1)) that transited the solar system in a hyperbolic orbit exhibits certain features that cannot be readily explained on the basis of it being a naturally-occurring comet or asteroid. The interesting conjecture by Bialy and Loeb that Ouamuamua (A/2017U1) could be an artificial construct of an alien civilization is re-examined. The possibility that Ouamuamua may be a dark cometary body, in which unobserved gaseous emissions may have led to departures from a Keplerian orbit, remains a more conservative alternative possibility. We discuss the implications of the discovery of light sails or similar artifacts, as proposed by Bialy and Loeb, in relation to the validity of galaxy-wide panspermia and the prevalence of life throughout the universe.

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A Robotic Camera for Monitoring Meteors Entering the Earth’s Atmosphere near the Equator

Authors: H.D.S. Amaradasa, G.D.K. Mahanama, S.S. Abeywickrama, A.G.P.D. Alahakoon, K.P.S.C. Jayarathna, N.C. Wickramasinghe

Abstract

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The systematic detection and tracking of meteor streams and global fireball events potentially provide a dataset of immense importance to our understanding of passing objects. To this end hemispherical and wide field of view cameras are used in meteor observations with a synchronized network of cameras to record intricate details about meteor activities. In this research a hemispherical robotic camera unit named AWITC was designed to monitor meteors entering earth’s atmosphere near Sri Lanka. The unit consists of an astronomy camera with a Complementary Metal Oxide Sensor (CMOS), a fish eye lens, a single board computer, a storage device, internet connectivity and other sensors allowing it to function with minimum human supervision. The images are saved with record of time, date and temperature. The time of the computer can be updated from both internet and GPS connections. The unit has two enclosures for protecting the electronics from solar radiation and rain and all the main devices reside in the internal enclosure. Temperature and humidity sensors are included to monitor the ventilation in the enclosure. A five element YAGI Wi- Fi antenna was designed to extend the wireless connectivity of the unit. The obtained images are saved in the internal storage and a copy is sent to a sever computer. All the software used, are uniquely developed for the unit and the cohesion of hardware and software were tested. The camera unit functioned for eleven months continuously and captured a large number of meteor activities.

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Luminosity Function of Arakelian Galaxies and Their Environmental Dependences

Authors: Abraham P. Mahtessian, Vardan G. Movsisyan, Lazar A. Mahtessian, Garen S. Karapetian

Abstract

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This article proposes a method for constructing the luminosity function of galaxies, which gives a result that is consistent with other methods, is as accurate as other methods, and is simple. Using this method, we constructed the luminosity function of Arakelian galaxies with different morphological types in different environments, included in the CfA2 catalog. The proposed method of identifying groups of galaxies is physically grounded and simple. It was found that both the bright and weak parts of the normalized luminosity function of Arakelian galaxies are higher than the bright and weak parts of the similar function of the total sample CfA2. A similar phenomenon is observed separately for members of groups, as well as for single galaxies. This also applies to small groups with 2 or 3 galaxies, and more populated groups. Spiral galaxies obey these laws. For elliptical galaxies, the picture is not very clear (due to the small number of well-known elliptical Arakelian galaxies). The spatial density of the number of ArG in the M≤-17 range is 0.00068 ± 0.00005 Mpc^-3, which corresponds to 2.7% of the entire sample in this range (for CfA2 (M≤-17) = 0.0254 ± 0.0002 Mpc^- 3).

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Calculation of Apsidal Precession via Perturbation Theory

Authors: L.Barbieri, F. Talamucci

Abstract

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The calculus of apsidal precession frequencies of the planets is developed by means of a perturbation technique. A model of concentric rings (ring model), suitable for improving calculations, is introduced. Conclusive remarks concerning a comparison between the theoretical, the calculated and the observed data of the precession frequencies are performed.