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Venus really is volcanically active, new study shows

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Venus is almost the same size, mass and density as Earth. So it should be generating heat in its interior (by the decay of radioactive elements) at much the same rate as the Earth does. On Earth, one of the main ways in which this heat leaks out is via volcanic eruptions. During an average year, at least 50 volcanoes erupt.

But despite decades of looking, we’ve not seen clear signs of volcanic eruptions on Venus – until now. A new study by geophysicist Robert Herrick of the University of Alaska, Fairbanks, which he reported this week at the Lunar & Planetary Science Conference in Houston and published in the journal Science, has at last caught one of the planet’s volcanoes in the act.

It’s not straightforward to study Venus’s surface because it has a dense atmosphere including an unbroken cloud layer at a height of 45-65km that is opaque to most wavelengths of radiation, including visible light.

The only way to get a detailed view of the ground from above the clouds is by radar directed downward from an orbiting spacecraft.

A technique known as aperture synthesis is used to build up an image of the surface. This combines the varying strength of the radar echos bounced back from the ground – including the time delay between transmission and receipt, plus slight shifts in frequency corresponding to whether the spacecraft is getting closer to or further from the origin of a particular echo.

The resulting image looks rather like a black and white photograph, except that the brighter areas usually correspond to rougher surfaces and the darker areas to smoother surfaces.

Nasa’s Magellan probe orbited Venus from August 1990 to October 1994 and used this sort of radar technique to map the planet’s surface with a spatial resolution of about a hundred metres at best.

It showed that over 80% of the surface is covered by lava flows, but just how recently the youngest of them were erupted, and whether any eruptions continue today, remained a mystery for the next three decades.

There have been various hints of activity provided by spacecraft peering into, and sometimes through, the clouds – suggesting that the rocks there are so young that their minerals have not yet been altered by reaction with the acidic atmosphere and so are freshly erupted lava.

Thermal anomalies that could correspond to active lava flows have also been detected, as have temporary local hiccups in the atmospheric sulphur dioxide concentration – another potential sign of volcanic eruptions. But none of these was fully convincing.

Volcanic vent spotted

The new study now seems to have settled the matter, by revealing changes on the surface that really have to be a result of volcanic activity. The authors spent hundreds of hours comparing Magellan radar images of parts of Venus that had been imaged more than once to look for new or changed features on the surface.

They concentrated on the most promising volcanic regions, and eventually spotted an example where details on an image recorded in October 1991 are different to those on an image from February of the same year. The changes they saw are best explained by a volcanic eruption within that time window.

Using radar images to verify surface changes is tricky because the appearance of even an unchanging surface can differ according to surface slopes and direction of view. However, the researchers performed simulations to verify that the observed changes could not result from these things.

The paired images show an initially near circular volcanic crater about 1.5km across that between February and October doubled in size by extending eastwards. It also became shallower, and the authors suggest that the crater is a volcanic vent that partially collapsed and was largely filled by fresh lava during October.

There are probably also new lava flows extending several kilometres down slope, northwards of the crater, which either flooded over the crater rim or leaked out of an associated fissure. The active crater sits high on Maat Mons, one of Venus’s largest volcanoes whose summit is 5km above the surrounding plains.

Future missions

Most planetary scientists already expected Venus to be volcanically active. The focus of attention will now surely turn to how often, and at how many sites, are eruptions occurring on Venus.

The biggest surprise in all this is that it took so long for someone to find the evidence for surface changes that had been lurking in the Magellan data for 30 years.

The likelihood of finding and studying ongoing volcanism is one of the main drivers for Nasa’s Veritas mission and Esa’s EnVision mission (both approved in 2021). Each will carry a better imaging radar than Magellan.

EnVision is intended to reach its orbit about Venus in 2034. Originally Veritas should have been there several years beforehand, but there have been delays to the schedule.

With Nasa’s DaVinci mission likely to arrive year or two ahead of them, providing optical images from below the clouds during its descent, we are in for an exciting time about ten years from now.

David Rothery, Professor of Planetary Geosciences, The Open University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Former US Air Force fighter pilot: UFOs use Star Trek-style warp drive

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A former US Air Force fighter pilot asserts that he has deciphered
the method behind the extraordinary maneuvers of UFOs, reports dailystar.co.uk.

Over
the past two decades, numerous military encounters with these enigmatic
crafts have been reported, prompting a significant investigation by the
Pentagon.

One of the most renowned sightings occurred during the
USS Nimitz encounter, where fighter pilots witnessed a UFO descending
from 28,000 feet to just above sea level in less than a second.

This
astonishing movement would imply that the craft reached a staggering
speed of 19,000 miles per hour, a velocity that would be fatal to any
human pilot.

According
to Chris Lehto, a former USAF pilot, the craft exhibits two key
characteristics: it moves without inertia, essentially lacking weight,
and it accelerates at an incredibly rapid pace without affecting its
surroundings.

Image: NATO Allied Air Command/Facebook

Chris
believes that the explanation lies within a technology that seems
straight out of science fiction. He proposes that the answer to the UFO
enigma lies in the Alcubierre Drive, a theoretical interstellar engine
conceptualized by Mexican physicist Miguel Alcubierre in 1994.

The
Alcubierre Drive employs a form of “space warp” technology, reminiscent
of what has been depicted in episodes of Star Trek. By bending space, a
craft inside a “warp bubble” could potentially travel at or even
surpass the speed of light without violating the known laws of physics.

While
the Alcubierre Drive remains a hypothetical concept with challenges to
overcome, Chris notes that the required energy is no longer believed to
be unattainably large.

Patents
filed with the US patent office outline the potential workings of the
drive, as well as another groundbreaking technology theorized by
American aerospace engineer Salvatore Pais.

Pais suggests that
high-powered rotating magnets could theoretically eliminate an object’s
inertia, and he has filed a patent for a starship based on this
principle.

However, Chris maintains skepticism regarding Pais’
theory. He explains that while Pais’s patent applications for the US
Navy attracted attention for their potential energy-related
applications, doubts have been raised about their feasibility. There is
speculation that they may be scams, pseudoscience, or disinformation
intended to mislead adversaries of the United States.

Alternatively,
rival theories propose that the “Tic Tac” UFO is a classified Pentagon
project testing similar advanced technologies discussed by Chris.

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A Mysterious Earth-Like Planet Has Just Appeared in Our Solar System, Scientists Say

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Scientists say they have found evidence of a new Earth-like
planet that has suddenly appeared in our Solar System and is orbiting
the Sun.

Physicists, including those from the National Astronomical Observatory
of Japan, said the planet is likely to be the mysterious ‘Planet Nine’
that was hypothesised to exist in the far outer edges of the Solar
System.

Several studies in the past have suggested there is likely an
undiscovered planet beyond the Kuiper Belt – a stellar disk of materials
such as asteroids, space rocks, comets around the Sun in the outer
Solar System past the orbit of Neptune.

Independent.co.uk reports: In the new research, published recently in The Astronomical Journal, scientists
found that some of the objects in the Kuiper Belt behave in a way
indicative of the presence of a small planet among them.

One such object, they said, is about 500 astronomical units (AU) from
the Sun, where 1 AU is the distance between the Sun and the Earth.

In comparison Neptune is at a distance of 30 AUs from the Sun.

Some of these were also found to have “odd” orbits suggesting they
are being pull by the gravity of a cosmic entity larger than those that
typically influence such objects.

Computer simulations run by the scientists indicate that the most
likely explanation for the observations was another hidden planet in the
Kuiper Belt.

“We predict the existence of an Earth-like planet,” researchers wrote in the study.

“It is plausible that a primordial planetary body could survive in
the distant Kuiper Belt as a Kuiper Belt planet (KBP), as many such
bodies existed in the early solar system,” they added.

If such a planet exists, researchers say it would have a mass about
1.5 to 3 times that of Earth with an inclination of about 30 degrees.

They say the theorised planet’s orbit would likely place it between 250 and 500 AU from the Sun.

Researchers say the discovery of such a planet close to the Kuiper
Belt can unravel new constraints on planet formation and evolution.

“In conclusion, the results of the KBP scenario support the existence
of a yet-undiscovered planet in the far outer solar system,” scientists
noted.

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