Date: 9/03/2015 14:51:37
From: Cymek
ID: 690692
Subject: Mars go boom?

If a remnant nuclear weapon had exploded on Mars, how long would a mushroom cloud last and would it look the same as a nuclear weapon detonated on Earth, also could you detect the flash of a nuclear explosion from Earth.

http://www.news.com.au/technology/science/debunking-the-tale-that-a-nuclear-explosion-has-been-photographed-on-the-surface-of-mars/story-fnjwlcze-1227255077072

IT’S a favourite among Red Planet conspiracy theorists: That a massive nuclear war scorched Mars lifeless.

Now a new photo is being bundled among the “evidence”.

A long-dead civilisation. Scattered remains among the red dust. Now the mushroom cloud from a long-dead war?

The idea of a long lost Martian civilisation has been around ever since NASA astronomers innocently quipped that they had found a “face” etched into the landscape in photographs beamed back by the Viking 1 spacecraft in 1976.

Grainy, fuzzy photos were scoured. Dots connected. Lines aligned.

Soon, an entire city — complete with pyramids — emerged from the Martian desert.

At least for some.

Books were written. Speeches were given.

But every time a space probe managed to take another, closer look — these carefully crafted interpretations would vanish in a puff of logic.

Now this photo is erupting into the popular culture battlefield.

PHOTO-REALISTIC

An innocuous colour image beamed back from India’s Mars Orbiter Mission on November 5 captures the famous Valles Marineris Canyon — an enormous scar carved into the surface of Mars. It makes the Grand Canyon look like an afterthought.

Then someone noticed something strange in the bottom left corner.

A mushroom cloud. Therefore aliens.

The original Mars Orbiter Mission image has since been resized, enhanced and explained.

“Images taken by Mars Colour Camera (MCC) on-board show the mysterious cloud with great clarity. The cloud is situated above the Valles Marineris Canyon. Its distinct mushroom shape and close-up views, depict what seems to be a large crater formed underneath the cloud,” writes news website DNA India.

Mysteriousuniverse.org is equally convinced: “It’s definitely mushroomed-shape and enlarged views of it show what looks like a crater formed underneath the cloud and a shadow of the cloud extending from it across the surface.”

Is it?

The Indian news blog takes the topic several steps further, reporting speculation as to the cause of the Valles Marineris Canyon “plume”.

Was it a remnant of the recently-passed comet Siding Spring scoring an impact? Was it a methane eruption like those which have recently caused craters to form in Siberia? Was it a simple dust cloud?

But there was also a more extreme explanation offered: A nuclear mushroom cloud.

“The discovery calls into question if the cloud exploded from an old bomb from a war,” the news blog writes.

What?

The Indian media organisation refers to a recent book, Death on Mars: The Discovery of a Planetary Nuclear Massacre.

The author’s name has a Dr in front of it: Dr John Brandenburg. He is a real physicist with a history of working as a propulsion researcher for a string of US aerospace firms. And he’s actually made a presentation on the subject to the annual meeting of the American Physical Society (Physics).

Think that’s an awfully long bow to draw?

“It’s simply like one of those magic eye picture tricks — the eye getting deceived and trying to see something where there isn’t really anything,” says astrobiologist Dr Jonathan Horner of the University of Southern Queensland.

Monash University astrophysicist Michael Brown is not impressed.

“From Mars to vaccines to climate you see cranks making wild claims at odds with the data and the meticulous work of professional scientists,” he says. “These claims often escalate to accusations of cover-ups and criminal activity, and unfortunately these sometimes get media coverage.”

THE STORY SO FAR

The Mars nuclear war story has seen something of a revival in recent months.

“Analysis of recent Mars isotopic, gamma ray, and imaging data supports the hypothesis that perhaps two immense thermonuclear explosions occurred on Mars in the distant past and these explosions were targeted on sites of previously reported artefacts,” Dr Brandenburg wrote in November last year.

Cydonia.

It’s a region of Mars where the infamous “Face On Mars” was found all those years ago.

“Imagery at the radioactive centres of the explosions shows no craters, consistent with airbursts,” he writes. “Explosions appear correlated with the sites of reported artefacts at Cydonia Mensa and Galaxias Chaos … Taken together, the data requires that the hypothesis of Mars as the site of an ancient planetary nuclear massacre, must now be considered.”

Cydonia is part of Mars northern hemisphere, between two distinctive craters — Arandas Crater and Bamberg Crater. It’s also on the verge of a relatively smooth plain that may have once been a seabed, and a heavily cratered area which extends southward.

But some see it as the site of a ruined extraterrestrial city, home to a long-lost Martian civilisation.

It’s an idea that has inspired a string of science fiction movies and television episodes.

A CLOSER LOOK

There is no mushroom cloud.

“Fun as it would be to imagine that this is evidence of nuclear weapons on Mars, or even the impact of a chunk of Comet Siding Spring smashing into the planet, that’s sadly just not the case,” Dr Horner says.

India’s Mars Orbiter Mission entered orbit above the Red Planet on September 24 last year. It has a colour camera on board. But it’s not terribly high resolution, such as those by the Mars Global Surveyor and the HiRISE camera aboard the Mars Reconnaissance Orbiter.

That’s for a reason: Its primary mission is to look for methane. Not map the weather or surface.

But it does show something that has already been mapped in minute detail: The Mariner Canyon.

“Valles Marineris is amazing, dwarfing the Grand Canyon in both size and depth,” Dr Brown says. “It is 7km deep in places and at 4000km long, so if you placed it on Earth it would stretch across Australia or the United States.”

The optical illusion is caused by the junction of a crater with the trench.

You can see for yourself.

Compare the light and dark spaces to other parts of the canyon. Illuminated cliffs, dark depths and the long shadows of mountains.

The lighting is very similar. The shapes are very similar. The colours are very similar.

It’s an arrangement of light and shadow which we can interpret as being a mushroom cloud.

Pareidolia: The trick the mind plays where you see rabbits in fuzzy clouds.

“If you have a look at wide pictures of Mars, you can see the area of the ‘mushroom cloud’ with sunlight at a different angle, and slightly different resolution and angle — and it’s clear that the “cloud”, and “stem” are just areas of darker material on the surface,” Dr Horner says.

Valles Marineris

Such recent photos of it are significant because of the tales they tell — about water.

“Valles Marineris shows signs of weathering that may have been produced by flowing water, and Mars may once have been a far wetter place than the dry dusty planet we see today,” Dr Brown says.

“You can start to explore the Valles Marineris yourself”

NASA, having accidentally started the whole thing with its 1976 caption, has devoted some effort towards setting the record straight. It has a page dedicated to comparing new and old images of the Cydonia region.

The result?

It’s the same story for the Face on Mars.

The lumpy hill that kind of looked like it could be a face in low resolution hasn’t stood the high-resolution test. It now looks like a lumpy hill.

The pyramids? Well they look like hills, too.

LAST CHANCE TO SEE?

Dr Brandenberg has taken his interpretations to the extreme:

“It is possible … that our interstellar neighbourhood contains forces hostile to young, noisy, civilisations such as ourselves,” he says.

“Such hostile forces could range from things as alien as AI (Artificial Intelligence) ‘with a grudge’ against flesh and blood, as in the movie Terminator, all the way to things as sadly familiar to us as a mindless humanoid bureaucrat like Governor Tarkin in Star Wars, eager to destroy planet Alderann as an example to other worlds.”

Or not.

“It’s standard crank behaviour to not consider mundane scenarios (such as image contrast), to leap towards extreme conclusions (e.g., mushroom cloud rather than dust) and then make conspiratorial claims,” Dr Brown says.

“There is no conspiracy,” Dr Horner says, “there’s just an old crater at the end of a valley, next to terrain that shows evidence that water may once have flowed on the surface of Mars,” Dr Horner adds.

It’s over to you, Mars Orbiter.

Reply Quote

Date: 9/03/2015 21:25:48
From: mollwollfumble
ID: 690957
Subject: re: Mars go boom?

> If a nuclear weapon had exploded on Mars, how long would a mushroom cloud last and would it look the same as a nuclear weapon detonated on Earth, also could you detect the flash of a nuclear explosion from Earth.

A long post, but a very interesting couple of questions.

For a nuclear explosion on Earth, 35% to 45% of the energy is released as light and heat, 4% as gamma rays, and 1% as neutrons. Sunlight on Mars is between 500 and 700 Watts per square metre. The albedo of Mars is 17%. The diameter of Mars is 36 million square km. So the sunlight we see from Mars leaves there with a total energy of 0.17*600*36*10^12 Watts, which is 3.7*10^15 Watts. The flash from a nuclear explosion

A 1 megaton nuclear explosion is 4.18*10^15 Joules, of which about 40% or 1.7*10^15 Joules is released as light and heat. One Watt is one Joule per second. So a 1 megaton nuclear explosion releases as much light and heat as the whole as the rest of Mars over a period of 1.7/3.7 = 0.46 seconds. This is not too different from the duration of the flash. So yes, the flash from a nuclear explosion on Mars, if it was on the side facing the Earth, would be very easily visible from Earth.

If it was on the side not facing the Earth, then the bulk of Mars would stop most of the light, gamma rays and neutrons from the nuclear blast. The neutrinos from it would tend to be lost among the much brighter neutrino source in the centre of the Sun. So we wouldn’t see it. If we still had a working seismometer on Mars then that would detect a nuclear explosion (or asteroid impact) on the far side of Mars with ease, but there are currently no working seismometers on Mars.

As for the mushroom cloud …

Reply Quote

Date: 9/03/2015 21:41:27
From: mollwollfumble
ID: 690972
Subject: re: Mars go boom?

As for the mushroom cloud …

The density of Mars’ atmosphere at the surface in 2% of Earth’s. That means that the fireball on Mars will be bigger in diameter by a factor of about sqrt(1/0.02) = 7 compared to that on Earth. The rise rate due to buoyancy of this fireball would be much slower than on Earth, at least 50 times slower. Would you get a mushroom cloud? I’d say yes, the plume will rise until gravity halts the rise, which I suspect would be at a greater height than on Earth because the gravity is weaker for one thing, and air resistance is less. At that point the plume would tend to spread out sideways, like in a mushroom cloud but without the strong vortex ring of a mushroom cloud on Earth.

Reply Quote

Date: 9/03/2015 21:51:54
From: mollwollfumble
ID: 690982
Subject: re: Mars go boom?

Dust from the mushroom cloud on Mars would fall back faster than an equivalent cloud on Earth, mainly because of the combination of lower atmospheric density, less atmospheric turbulence, and smaller amount of Brownian motion in the atmosphere of Mars because of the lower upper-atmosphere temperature. Brownian motion, by the way, dominates the descent rate of the smallest particles in the cloud.

The tendency towards more rapid settling is opposed by the higher cloud altitude on Mars and the lower gravitational pull. But I still say that the dust would settle faster on Mars than on Earth, because the settling depends more on atmospheric density and turbulence than on gravity and starting altitude. The settling would take of the rough order of three months.

Reply Quote

Date: 9/03/2015 22:41:56
From: wookiemeister
ID: 691016
Subject: re: Mars go boom?

the mushroom of a nuclear weapon detonation is caused by the atmosphere, lots of gas that gets heated rapidly pushed outwards then collapsing back to the lower pressure zone

mars has less atmosphere, much less atmosphere so there’ll be less mushroom, much less mushroom

if you want spectacular mushroom blasts go to venus and set off a bomb there

Reply Quote

Date: 9/03/2015 22:49:33
From: wookiemeister
ID: 691019
Subject: re: Mars go boom?

the americans are testing nuclear weapons on mars in contravention of nuclear treaties

by testing on mars they evade all agreements with Russia because mars is normally so far away no one normally sees the blasts – until now

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Date: 13/03/2015 11:25:52
From: Cymek
ID: 692455
Subject: re: Mars go boom?

Don’t nuclear weapon decay and become unrealiable after only a few decades, I thought that was one of the reasons the Ruskies and the Septics reduced their nuclear arsenal as the upkeep of them was expensive and dangerous,

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