OTHER | LIFE ON VENUS & SEARCH FOR EXTRATERRESTRIAL INTELLIGENCE

LIFE ON M̶A̶R̶S̶ VENUS???

Me - looking at the TV thinking of the Fermi Paradox

Oh Venus, who would think that of all planets YOU would render us the big surprise???

Ah, yes, EVERYONE THAT LIVED UP TO THE SECOND HALF OF THE 20th CENTURY.

This Monday hasn't been a good one for me, but when mom told me to watch TV I felt I had to sit and write about this - so here we go.

WHAT HAPPENED...

FIRST

Venus, is the second planet from the Sun, slightly less massive and smaller than Earth short of 600-ish km, since the invention of the telescope and up to the Space Race in the mid 20th century, we thought that Venus could and did harbor life like our own here on Earth.

From afar we saw it's clouds obscuring it's surface, which we thought initially to be water clouds - it would make sense to us at the time those clouds would be like those on Earth, Venus were well known to be closer to the Sun - so the extra heat would indeed rise more vapor to the atmosphere - for over 150 years, our view of Venus was this steamy swamp-like world.

In 1962, the Soviet Union tried contact with a supposed venusian civilization, transmitting the words "Peace/World", "Lenin", and "USSR", in russian morse code - the first deliberate radio broadcast for an extraterrestrial civilization.

Since 1974, there has been 34 attempts to contact individual star systems, with yet to arrive years ranging from 2022 to 27000.

SECOND

Since the 1960s our probes and satellites have shown us that the layers of Venus' atmosphere are composed of sulfuric acid and carbon dioxide, which is destructive to life, with and atmospheric pressure which is over 92x higher than Earth's - and the surface temperature is over 470°C on average.

Even though Earth's extremophiles are found to survive in places where the temperatures are around 100~121°C (in this case - around a deep-sea blacksmoker).

However, life doesn't need to be on the surface of Venus to survive - Carl Sagan and Harold Morowitz had proposed in 1967 - that life forms could have evolved airbone in the atmosphere of Venus - altitudes between 45 and 60 km hold the limits -20°C to 120°C and reasonable pressures, from 1,97 to 0,23 atm. Therefore, it's not far fetched the existence of organisms in the Venusian clouds.

MONDAY, 14 SEPTEMBER 2020

It was announced that a biomarker - phosphine (which is used as bioweapon and pesticide in crops) in an amount that cannot be explained by abiogenic processes, those whose would maintain a ~10ppb of atmospheric phosphine - but around 20 parts per billion was found in the atmosphere of Venus. This is considered as evidence of the possible existence of microbial life on this planet or some photochemical or geochemical processes unknown to us at this time.

IMPLICATIONS ON THE SEARCH FOR EXTRATERRESTRIAL INTELLIGENCE

There isn't much we can do other than speculate at the moment - the only active mission to Venus as of this day is the Akatsuki probe which takes atmospheric measurements from space.

Every other natural way astrophysiscists thought this phosphine would have gotten there, requires unrealistic assumptions, such as Venus being over 200x to 100 MILLION times more volcanically active than the Earth, we have at least 100k volcanoes from the last 100Myr, while Venus had produced ~70k, over the last 500~1000Myr, seemingly Venus is 1/10 as active as Earth is.

If confirmed to be a biotic process, ie Venus is home to microbial-life forms, we can already re-do our Drake Equations:

Using the recent stats for star formation, between 7 stars per year, with 1/5 of those having planets, considering a system with 10 planets - where 3 would be suitable for life, we have 2/3rds of those planets actually harboring life, where 1 develops intelligent life, where 1 out of 9 intelligent species manage to produce interstellar radio communications for 1000 years, we have:

1.677.060.000 (1,67 billion) civilizations we might be able to communicate with.

Using a system of 5 planets, 3,35 billion;

Using 10 planets, 2~3 that are potentially suitable but 1/22 intelligent species actually thrive, 571,72 million;

Using 10 planets, 2~3 that are potentially suitable, 1/22 intelligent species actually thrive, but actually considers only one planet to harbor life, 285,86 million;

Using our first number, we have an average of 0,0002 civilizations per cubic light-year, or ~100-ish ly in between homeworlds.


MANKIND'S DESPERATE ATTEMPTS TO SAY "HELLO"

So given the stars we've chosen to make contact so far, our chances of actually making contact with someone else out there, are virtually zero, as most are within 50-ish light-years from Earth, and the ones +100ly away are stars pinned uninhabitable or inadequate for life to arise, such as Polaris and Spica.

The 1974 Arecibo Message in this aspect, has poorly chosen Messier 13 cluster as it's target, not only because it's 27Kly away so we may not even be around by the time the message arrives, but because the M13 cluster will have moved away from where we've sent the message in 27kyr.

The lack of replies, or even foreign attempts to contact Earth - may imply that either no one else in the vicinity of Earth has reached or got even close to Kardashev I tier - consider a civilization that's 1000 years into the K-I tier, 1000ly away, we should be able to at least hear their first radio transmissions and beacons, not to speak of possible nearby colonies and outposts - is safe to assume that if there are extraterrestrial civilizations around other stars, they are either considerably inferior to ourselves in technology, or are in a near-future reaching our level of technology, ie, are K ≤ 0,7.

- M.O. Valent, 15/09/2020