The Milky
Way Galaxy resides in a neighborhood of a few dozen galaxies called the Local
Group. They range in size from small dwarf galaxies to the large Andromeda
Galaxy. Over time, these galaxies interact with one another, changing their
motions and shapes. The long-term evolution of a galaxy is influenced by being
part of a group. The Milky Way and the Andromeda Galaxy, our nearest spiral
neighbor, are headed toward each other. In about five billion years, they may
collide and merge. Eventually, our remote descendants could be living in a
large elliptical galaxy.
The ultimate aim,
fear, curiosity, research, thought, goal of humanity perhaps is in finding out whether
there exists life outside our planet – are there any neighbours living in any
nearby planet, galaxy or elsewhere. NASA's
exoplanet program is to find unmistakable signs of current life on a planet
beyond Earth. How soon that can happen depends on two unknowns: the prevalence
of life in the galaxy and how lucky we get as we take those first, tentative,
exploratory steps.
Nothing about
2020 surprises us anymore. It has been the year of pandemics, wildfires,
asteroids zooming past Earth and now, aliens.
Scientists
said on Monday that they have detected in the harshly acidic clouds of Venus, a
gas called phosphine, that indicates microbes may inhabit Earth’s inhospitable
neighbour, a tantalizing sign of potential life beyond Earth. This could be indicative of the presence of
alien life on a planet that has always been described as inhospitable.
Don’t get
carried by the word ‘neighbour’ – Venus is the closest planet to Earth (it's
also the most similar in size). But its proximity to our planet depends on the
orbits of both. The two planets travel in ellipses around the sun, and so the
distance between them is constantly shifting. At its farthest, Venus lies 162
million miles (261 million kilometers) away, according to NASA. Venus takes
224.7 Earth days to travel around the sun. It makes its closest approach to
Earth about once every 584 days, when the planets catch up to one another. On
average, it is 25 million miles (40 million km) away at this point, though it
can reach as close as 24 million miles (38 million km).
Most astronomers feel that it would be impossible for life to exist on Venus as it is a very hostile place. It is a very dry planet with no evidence of water, its surface temperature is hot enough to melt lead, and its atmosphere is so thick that the air pressure on its surface is over 90 times that on Earth. Even the spacecraft which have landed on Venus only survived for about an hour before being crushed and melted. There are however, a few scientists who think that it is possible for life to exist in the clouds of Venus.
Tyazhely Sputnik, also
known by its development name as Venera 1VA No.1, and in the West as Sputnik 7, was a Soviet
spacecraft, which was intended to be the first spacecraft to explore Venus. Due
to a problem with its upper stage it failed to leave low Earth orbit. In order
to avoid acknowledging the failure, the Soviet government instead announced
that the entire spacecraft, including the upper stage, was a test of a
"Heavy Satellite" which would serve as a launch platform for future
missions. Tyazhely Sputnik was launched
at 01:18:03 UTC on 4 Feb 1961, atop a Molniya 8K78 carrier rocket flying from
Site 1/5 at the Baikonur Cosmodrome. When the upper stage ignited, cavitation
in the liquid oxygen flowing through the oxidiser pump caused the pump to fail,
resulting in an engine failure eight-tenths of a second after ignition. It
reentered the atmosphere over Siberia on 26 Feb 1961.
After that mission, several landers from the former Soviet Union
have landed on Venus. They were only able to send information for a short time because the
extremely high temperature and pressure on the surface of Venus melted and
crushed the landers. On Dec 15, 1970 an unmanned Soviet spacecraft, Venera 7,
became the first spacecraft to land on another planet. It measured the
temperature of the atmosphere on Venus. In 1972, Venera 8 gathered atmospheric
and surface data for 50 minutes after landing. In 1975, Venera 9 landed on the surface of Venus.
It took the first close-up photograph of the planet's surface. Three days later
Venera 10 landed on Venus. Venera 10 took photographs of its surface and
studied its rocks.
Phosphine is
the compound with the chemical formula PH3, classed as a pnictogen hydride. It
is a colorless, flammable, very toxic gas. Pure phosphine is odorless, but
technical grade samples have a highly unpleasant odor like garlic or rotting
fish, due to the presence of substituted phosphine and diphosphane (P2H4). With
traces of P2H4 present, PH3 is spontaneously flammable in air (pyrophoric),
burning with a luminous flame.
Venus is the second planet
from the Sun. It is named after the Roman goddess of love and beauty. As the
second-brightest natural object in the night sky after the Moon, Venus can cast
shadows. Venus lies within Earth's orbit, and so never
appears to venture far from the Sun, either setting in the west just after dusk
or rising in the east a bit before dawn. Venus orbits the Sun every 224.7 Earth
days. With a rotation period of 243
Earth days, it takes longer to rotate about its axis than any other planet in
the Solar System and does so in the opposite direction to all but Uranus
(meaning the Sun rises in the west and sets in the east). Venus does not have any moons, a distinction
it shares only with Mercury among planets in the Solar System.
PS 1 : Philippe Gengembre (1764–1838), a student of
Lavoisier, first obtained phosphine in 1783 by heating white phosphorus in an
aqueous solution of potash (potassium carbonate). Perhaps because of its strong association
with elemental phosphorus, phosphine was once regarded as a gaseous form of the
element, but Lavoisier (1789) recognised it as a combination of phosphorus with
hydrogen and described it as phosphure d'hydrogène (phosphide of hydrogen).
PS 2 : the woman at the start - Venus Williams (Venus Ebony Starr Williams) is
the famous sister of Serena Williams and together they have dominated
Professional tennis. A former world No. 1 in both singles and
doubles, Venus Williams is generally
regarded as one of the all-time greats of women's tennis and, along with
younger sister Serena Williams, is credited with ushering in a new era of power
and athleticism on the women's professional tennis tour.
PS 3: Nightflight to Venus is the third studio
album by Euro-Caribbean group Boney M., and was released in July 1978. The
album became a major success in continental Europe, Scandinavia, and Canada, topping
most of the album charts during the second half of 1978 and also became their
first UK number one album. Nightflight to Venus includes their worldwide
hits "Rivers of Babylon" and "Brown Girl in the Ring", a
double A-sided single that topped the UK singles chart and has sold over 2
million copies there.
Interesting !
15.09.2020.
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