Abstract
The Drake formula is a statistical method of forecasting the possible number N of technically evolved extraterrestrial and galactic civilizations able to communicate with the human species. It is based on seven different factors that can be grouped into factors of type A, fA (“Astrophysicist”) and type B, fB (“Astrobiological”). The quantitative analysis of these factors at the time of the presentation of the formula was subjective and highly variable for both factors fA and fB. Current scientifical and technological development has made it possible to refine the quantitative estimates of the fA group whose definition is now less uncertain. In group fA the parameter ne is understood as the number of planets capable of sustaining life. By means of ne Drake defines this possibility exclusively from the geometric point of view. In particular, the planet’s orbit must be included in the circumstellar space in which the planetary temperature allows the presence of liquid water. This is not enough because, for liquid (and gaseous) water to be present on the planet’s surface, it is also essential that the planet has a magnetic field of adequate intensity to shield the flow of charged particles coming from its star (solar wind). The solar wind is able to break up and disperse the liquid and gaseous water molecules and any organic molecules in times much shorter than theoretically necessary for the formation of life and above all, except for singularities, than necessary for evolution to arrive at intelligent life. Here the planetary magnetic field parameter nm is introduced into the Drake formula and its statistical probability of existence is discussed.
Highlights
The solar wind on both days Q and D, if not shielded from the planetary magnetic field, would reach the surface of the planet [5]. This physical condition can generate at least two lethal effects for the hypothesis of life: - direct and destabilizing interaction with the structure of organic molecules; - destructuring interaction with liquid and gaseous water molecules; water and organic molecules would be swept away from the planet’s surface which would be sterilized [6]. This effect heavily affects the statistical evaluation proposed by Drake and the probability of the presence of the planetary magnetic field must be inserted in the formula as factor nm. nm represents the percentage of rocky planets that possess a magnetic field of suitable intensity to shield the solar wind
The geomagnetic field existence in the space around the planet Earth provides an effective shield against the flow of charged particles of solar origin and against their interplanetary magnetic field IMF
Q and D solar wind flow conditions would be a serious obstacle to the stability of the basic organic molecules of life and to life itself and, most likely, to the lasting survival of a terrestrial type atmosphere and liquid water on the planet’s surface
Summary
The solar wind on both days Q and D, if not shielded from the planetary magnetic field, would reach the surface of the planet [5] This physical condition can generate at least two lethal effects for the hypothesis of life (even before intelligent life): - direct and destabilizing interaction with the structure of organic molecules; - destructuring interaction with liquid and gaseous water molecules; water and organic molecules would be swept away from the planet’s surface which would be sterilized [6]. This effect heavily affects the statistical evaluation proposed by Drake and the probability of the presence of the planetary magnetic field must be inserted in the formula as factor nm (planetary magnetic field). This effect heavily affects the statistical evaluation proposed by Drake and the probability of the presence of the planetary magnetic field must be inserted in the formula as factor nm (planetary magnetic field). nm represents the percentage of rocky planets that possess a magnetic field of suitable intensity to shield the solar wind
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
