Related papers: Comets, historical records and vedic literature
In 1883, on the 12th and 13th of August, Mexican astronomer Jose A. y Bonilla observed several objects passing in front of the solar disk. In 1886 in the L'Astronomie magazine, he reported his observations without providing a hypothesis…
Small bodies in the solar system are conventionally classified into asteroids and comets. However, it is recently found that a small number of objects can exhibit properties of both asteroids and comets. Some are more consistent with…
Comet disintegration proceeds both through sublimation and discrete splitting events. The cross-sectional area of material ejected by a comet may, within days, become many times greater than that of the Earth, making encounters with such…
Celestial objects, from earth like planets to clusters of galaxies, possess angular momentum and magnetic fields. Here we compare the rotational and magnetic energies of a whole range of these celestial objects together with their…
Comets are primitive objects that formed in the protoplanetary disk, and have been largely preserved over the history of the Solar System. However, they are not pristine, and surfaces of cometary nuclei do evolve. In order to understand the…
Planetary nebulae often have asymmetric shapes, which could arise due to collimated jets from evolved stars before evolution to the planetary nebula phase. The source of jet collimation in these stars is unknown. Magnetic fields are thought…
Comets hold the key to the understanding of our solar system, its formation and its evolution, and to the fundamental plasma processes at work both in it and beyond it. A comet nucleus emits gas as it is heated by the sunlight. The gas…
Remote investigations of the ancient solar system matter has been traditionally carried out through the observations of long-period (LP) comets that are less affected by solar irradiation than the short-period counterparts orbiting much…
The Hubble Space Telescope has recently discovered thousands of gigantic comet-like objects in a ring around the central star in the nearest planetary nebula. We suggest that such circumstellar rings exist around most stars. Collisions of…
The physical basis of chaos in the solar system is now better understood: in all cases investigated so far, chaotic orbits result from overlapping resonances. Perhaps the clearest examples are found in the asteroid belt. Overlapping…
The motion of celestial bodies in astronomy is closely related to the orbits of electrons encircling an atomic nucleus. Bohr and Sommerfeld presented a quantization scheme of the classical orbits to analyze the eigenstates of the hydrogen…
Watchings of Canopus as a herald of the winter were important duties of ancient priests-astronomers on Easter Island. All the analysed data witness that this star was observed during the first and second voyages from Mangareva to the…
Common envelope events have been associated with the formation of a planetary nebulae since its proposition more than forty five years ago. However, until recently there have been doubts as to whether a common envelope while the donor is…
In this article we review some key time cycles in ancient Indian astronomy, especially those that have emerged from researches in the past couple of decades expressing knowledge of the changing frame of earth's axis. The article also…
The author describes some stones which he found at the bottom of Khushmo River's shoal during 1988 expedition into the region of the Tunguska impact (1908). Photos of stones are presented. Three stones have traces of melting and the author…
Comet C/1995 O1 (Hale-Bopp) has provided an unprecedented opportunity to observe a bright comet over a wide range of heliocentric distances. We present here Spitzer Space Telescope observations of Hale-Bopp from 2005 and 2008 that show a…
According to general relativity (GR), a universe with a cosmological constant $\Lambda$, like ours, is trapped inside an event horizon, $r< \sqrt{3/\Lambda}$. What is outside? We show, using Israel (1967) junction conditions, that there…
Recent high-resolution observations from the Solar Dynamics Observatory (SDO) have reawakened interest in the old and fascinating phenomenon of solar tornado-like prominences. This class of prominences was first introduced by Pettit (1932),…
We discuss the connection between the chemistry of dense interstellar clouds and those characteristics of cometary matter that could be remnants of it. The chemical evolution observed to occur in molecular clouds is summarized and a model…
It has long been assumed that the planet Jupiter acts as a giant shield, significantly lowering the impact rate of minor bodies upon the Earth, and thus enabling the development and evolution of life in a collisional environment which is…