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Why Scientists Made Venus Flytraps That Glow

Provoking a Venus flytrap takes a certain amount of finesse. If you brush just one of the trigger hairs inside of its leaves, the plant likely won’t react. But if you trigger it again quickly enough, it will spring into action, swinging its famous mouth shut.

Waiting for a double trip probably keeps the plant from wasting energy on raindrops or other things that aren’t nutritious flies. But despite centuries of interest in the species, no one was quite certain how the plants remember the first trigger in order to act on a second.

In a paper published last week in Nature Plants, researchers reported they had found the cause: calcium ions. By inducing the flytraps to glow when calcium entered their cells, a team of scientists was able to show how the ions build up as the hairs are triggered, eventually causing the snap.

Calcium is used for conveying information between cells in many different life-forms, said Mitsuyasu Hasebe, the leader of the lab at the National Institute for Basic Biology in Okazaki, Japan, where the research was done. The molecule is normally “scarce in the cell, but abundant out of it,” he said, making it easy for cells to recognize and react to changes in concentration.

In 1988, a pair of plant scientists hypothesized that two overlapping rushes of calcium ions might spur the Venus flytrap to close, but had no way to test their idea. More recently, another group of researchers — including Rainer Hedrich, who participated in the new paper — solved part of the puzzle, showing that electrical signals tell the flytrap when its trigger hairs have been pressed. They also speculated that calcium helps the plant keep track.

To visualize the flytrap’s memory mechanism, Dr. Hasebe and his colleagues spliced a special type of gene into the plant. This gene, widely used in biology, produces a protein that turns fluorescent green when it binds to a target — in this case, a calcium ion.

Hiraku Suda — the paper’s lead author and a doctoral student in Dr. Hasebe’s lab at the time of the research — was in charge of integrating the gene, which required infecting the plant’s leaves with a modified bacterium and then using those leaves to grow new shoots.

It took him two and a half years to figure it out. The key, it turned out, was raising the plants in the dark, which may have made them easier to infect with the bacteria. When it finally worked, he was so excited, “I didn’t sleep for a week,” he said.

Next, the researchers started poking the plant. After a single tap to a sensory hair, a green flush appeared at the hair’s base and quickly spread across the leaves, indicating a surge of calcium ions.

A second tap within about 30 seconds spurred an additional surge, pushing the total calcium amount over a threshold that caused the trap to close. (In videos of the experiment, the glowing, chomping flytrap looks like

A well-timed Venus flyby looks for signs of life in the clouds

Just weeks after the reported discovery of phosphine on Venus – a potential sign of life in the clouds above its hellish surface – a robot spacecraft will study the planet as it swings by on its exploration of the solar system.

The BepiColombo space probe’s flyby above Venus at two minutes before midnight ET Wednesday is a coincidence.

The “gravity slingshot” was planned years ago, long before astronomers detected traces of phosphine in the Venusian atmosphere.

But it’s the first spacecraft to get near Venus since the discovery – although probably not the last – and measure gases in the planet’s atmosphere.

“We will look at what we see in the data, and look for everything – the expected and the unexpected,” said Jörn Helbert of the German Aerospace Center’s Institute of Planetary Research in Berlin, who works on a BepiColombo instrument called the Mercury Radiometer and Thermal Infrared Spectrometer.

That might include phosphine, but also sulfur dioxide, which would be a sign of ongoing volcanism, he said.

Last month’s discovery came too late to allow trajectory changes, and BepiColombo will only get within 6,700 miles of the surface – probably too far to detect phosphine at the reported concentrations of 20 parts-per-billion, Helbert said in an email.

But the upcoming flyby will give a better chance of detecting phosphine on a second flyby in August 2021, when BepiColombo will get within 400 miles of the Venusian surface.

“We will use the lessons learned from this flyby to optimize our observing strategy for the next flyby,” Helbert said. “The closer we get, the better the signal.”

BepiColombo launched two years ago on a seven-year voyage to Mercury, where it will deploy two orbiters – one European and one Japanese – to carry out scientific observations of the closest planet to the sun.

Wednesday’s flyby will be its first of two around Venus, followed by six around Mercury itself, to accelerate or decelerate and change its orbit around the sun.

It’s the most complex journey carried out by any spacecraft, and the probe is named after the Italian scientist Giuseppe “Bepi” Colombo, who calculated the Mariner 10 probe could decelerate around Venus to get to Mercury, a flyby carried out in 1974.

Slingshots using a planet’s gravity are now commonly employed to conserve fuel as spacecraft explore the solar system.

The Mercury Radiometer and Thermal Infrared Spectrometer is designed to study Mercury, and isn’t optimal for searching for phosphine on Venus, Helbert said.

It has a better chance, however, of measuring sulfur dioxide, which has been detected there at concentrations of up to 500 parts per billion – more than 20 times the estimated concentration of phosphine.

Sulfur dioxide is quickly destroyed by ultraviolet light, so high concentrations would suggest a volcano had recently erupted, he said.

Caleb Scharf, the director of astrobiology at Columbia University in New York, said the question of Venus’ volcanic activity was important to explain the chemistry of both its surface and its clouds.

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A well-timed Venus flyby looks for signs of life

Just weeks after the reported discovery of phosphine on Venus – a potential sign of life in the clouds above its hellish surface – a robot spacecraft will study the planet as it swings by on its exploration of the solar system.

The BepiColombo space probe’s flyby above Venus at two minutes before midnight ET Wednesday is a coincidence.

The “gravity slingshot” was planned years ago, long before astronomers detected traces of phosphine in the Venusian atmosphere.

But it’s the first spacecraft to get near Venus since the discovery – although probably not the last – and measure gases in the planet’s atmosphere.

“We will look at what we see in the data, and look for everything – the expected and the unexpected,” said Jörn Helbert of the German Aerospace Center’s Institute of Planetary Research in Berlin, who works on a BepiColombo instrument called the Mercury Radiometer and Thermal Infrared Spectrometer.

That might include phosphine, but also sulfur dioxide, which would be a sign of ongoing volcanism, he said.

Last month’s discovery came too late to allow trajectory changes, and BepiColombo will only get within 6,700 miles of the surface – probably too far to detect phosphine at the reported concentrations of 20 parts-per-billion, Helbert said in an email.

But the upcoming flyby will give a better chance of detecting phosphine on a second flyby in August 2021, when BepiColombo will get within 400 miles of the Venusian surface.

“We will use the lessons learned from this flyby to optimize our observing strategy for the next flyby,” Helbert said. “The closer we get, the better the signal.”

BepiColombo launched two years ago on a seven-year voyage to Mercury, where it will deploy two orbiters – one European and one Japanese – to carry out scientific observations of the closest planet to the sun.

Wednesday’s flyby will be its first of two around Venus, followed by six around Mercury itself, to accelerate or decelerate and change its orbit around the sun.

It’s the most complex journey carried out by any spacecraft, and the probe is named after the Italian scientist Giuseppe “Bepi” Colombo, who calculated the Mariner 10 probe could decelerate around Venus to get to Mercury, a flyby carried out in 1974.

Slingshots using a planet’s gravity are now commonly employed to conserve fuel as spacecraft explore the solar system.

The Mercury Radiometer and Thermal Infrared Spectrometer is designed to study Mercury, and isn’t optimal for searching for phosphine on Venus, Helbert said.

It has a better chance, however, of measuring sulfur dioxide, which has been detected there at concentrations of up to 500 parts per billion – more than 20 times the estimated concentration of phosphine.

Sulfur dioxide is quickly destroyed by ultraviolet light, so high concentrations would suggest a volcano had recently erupted, he said.

Caleb Scharf, the director of astrobiology at Columbia University in New York, said the question of Venus’ volcanic activity was important to explain the chemistry of both its surface and its

Mars At Its Brightest Since 2003 As Moon Visits Venus. What You Can See In The Night Sky This Week

Each week I pick out the northern hemisphere’s celestial highlights (mid-northern latitudes) for the week ahead, but be sure to check my main feed for more in-depth articles on stargazing, astronomy and eclipses. 

What To Watch For In The Night Sky This Week: October 12-18, 2020

This week it’s all about Mars, which will look its biggest, brightest and best in post-sunset skies since 2018 and, technically speaking, since 2003.

However, it’s also a week where the Moon wanes towards its New phase, meaning dark skies at night, gorgeous crescents in the early pre-dawn mornings early in the week, and in early evenings from Sunday. 

MORE FROM FORBESWhat’s That Really Bright ‘Star’ In The Night Sky?

Tuesday, October 13, 2020: Mars at opposition

Tonight the red planet reaches opposition, a moment when the Earth is between it and the Sun. It’s therefore at its biggest and brightest. It’s also visible all night, rising at dusk in the easy and setting at dawn in the west.

The opposition of Mars happens roughly every two years, though technically speaking, Mars is tonight bigger and brighter than at any time since 2003. 

MORE FROM FORBESYour Stargazing Guide To Fall: One ‘Halloween Blue Moon,’ Two Eclipses And A Once-In-397 Years Sight

Wednesday, October 14, 2020: Crescent Moon and Venus

Look east about an hour before sunrise this morning and you’ll see the glorious sight of a very bright 76%-illuminated planet Venus shining 4.3° above a delicate 1% illuminated crescent Moon.

Such a Moon is often called “the New Moon in the Old Moon’s arms.” You may see “Earthshine” on the Moon’s darkened limb. That’s sunlight being reflected off Earth and onto the Moon. It’s always there, but only when the Moon is a slender crescent can human eyes discern it. 

Look above Venus and you’ll also see Regulus, the brightest star in the constellation of Leo. 

Friday, October 16, 2020: New Moon and ‘Supermoon’

Although this isn’t something anyone can see—after all, a New Moon is lost in the Sun’s glare—our satellite will start anew today at 19:31 Universal Time.

It happens just a few hours after the Moon reaches its monthly perigee—the closest it comes to Earth on its slightly elliptical orbit—making this invisible New Moon a “supermoon.” Expect big tides. 

MORE FROM FORBESYour Stargazing Guide To October: Halley’s Comet Meteors, Dazzling Mars And Halloween’s ‘Blue Moon’

Constellation of the week: Cassiopeia

High in the northeast after dark is the constellation of Cassiopeia, the queen. It’s circumpolar, meaning it revolves around Polaris, the North Star. It’s thus almost always visible, and at this time of year it’s high in the

How could a toxic gas be a sign of life of Venus?

Scientists recently announced that they had found possible signs of life in the clouds of Venus. We probably should have suspected as much all along.

Venus is a natural place to look for life beyond Earth. It is Earth’s twin — almost the same size and structure — and closer to us than Mars, the current favorite of astronomers looking for life elsewhere in the solar system. Venus is also closer to the Sun, which provides the warmth necessary for life as we know it. In the past, a few scientists have suggested that Venus was a source of primordial life that was later seeded on Earth. That theory, lithopanspermia, never gained popularity because current conditions on Venus seemed very inhospitable to life. The high concentration of carbon dioxide in the atmosphere of Venus ensures that the planet has a runaway greenhouse effect that makes its surface incredibly hot, way hotter than your oven, which kills off microorganisms. And the clouds in its atmosphere are acidic. So scientists turned their attention elsewhere, to Mars and the moons of Saturn. So far, no definitive signs of life have been found on any of them.

But the latest announcement about Venus is a tantalizing one. Astronomers haven’t actually seen life on Venus. Instead, they have observed evidence of a gas called phosphine in the planet’s clouds. What could phosphine have to do with extraterrestrial life?

Phosphine is a highly toxic gas formed when one atom of phosphorus combines with three atoms of hydrogen. Giant planets such as Jupiter have a lot of hydrogen in them and in their atmospheres, and are known to produce phosphine. But on Venus and Earth, there is very little hydrogen in the atmosphere. So, the thinking goes, any phosphine detected is likely associated with life, because someone or something would have had to make it.

Humans produce phosphine industrially for use in computer chips, in flame retardants, and sometimes as a fumigant for rodents. It occasionally ends up as a byproduct in clandestine meth labs. The chemical is also made by microbes through a process that is not well understood, says Derek Lowe, a chemist who has studied phosphine. Typically, it is found in anaerobic (oxygen-free) environments where there is decaying organic matter. In the 1990s, two Swiss researchers found that phosphine was being produced by microbes in sewage, but when the sewage was irradiated, killing the microorganisms, the phosphine could no longer be detected. So phosphine seems to be indicative of life — a biomarker.

Venus’s atmosphere is mostly carbon dioxide, and any phosphine would chemically combine with that gas quickly. So the phosphine detected on Venus — at a concentration of about 20 parts per billion — is somehow being constantly replenished.

MIT astronomer Sara Seager and colleagues are hypothesizing that microbes in the clouds of Venus could be producing the telltale phosphine. These microbes would live high above the scorching temperatures of Venus’s surface, and they would have the ability to exist in a

Moon May Harbor Ancient Pieces Of Venus’ Surface

Two Yale University researchers have found a potential shortcut in sampling Venus’ ancient surface. Instead of sending a probe on a costly and extraordinarily challenging Venus sample return mission, they propose simply finding a Venusian meteorite on our own Moon.

There’s never been a bona fide detection of a Venusian meteorite on Earth. For one reason, that’s because in the last several hundred million years at least, Venus’ atmospheric pressures have been so intense that even a catastrophic impactor could not dislodge any Venusian rocks into space. 

But before Venus underwent a runaway greenhouse and morphed into the climatic hellhole it is today, it may have had liquid water oceans as late as 700 million years ago. If so, its atmosphere would have been thin enough for surface rocks to have been dislodged by massive impactors and possibly have found their way to both the Earth and our Moon. 

Due to weathering here on Earth, Venusian meteorites on Earth wouldn’t survive long. But because our Moon has no atmosphere, the authors of a paper accepted by The Planetary Science Journal posit that the Moon may have be the ideal spot to preserve Venus meteorites. 

Lead author Samuel Cabot and co-author Gregory Laughlin investigated the amount of material ejected from Venus when it suffered past impacts from asteroids and comets, and then traced the orbits of the rocks throughout the Solar System. They found that a small (but still significant) fraction of rocks ejected from Venus will be swept up by Earth’s Moon. 

Today, due to Venus’ thick atmosphere, even a catastrophic impactor would not be capable of ejecting material with a force to overcome drag from Venus’ thick atmospheric pressures.

But even if they found a Venus meteorite on the Moon or in Apollo rock samples, would researchers be able to offer a high degree of confidence that it originated on our sister planet? That is, in the same way that researchers have high confidence that the Allan Hills meteorite ALH84001 from Antarctica actually originated on Mars?

For an Allan Hills Martian meteorite, we can compare its composition to measurements made by Martian rovers, Cabot, a graduate student in Yale’s Department of Astronomy, told me.  A Venusian meteorite would lie in a completely new category from the rest, but require some extra work, he says. Several samples, plus some comparison to Venus’ current atmosphere, would help single out Venus as the place of origin, Cabot explains.

However, the degree of confidence in a putative Venus meteorite would not be as high as for Martian meteorites, As Laughlin, a Yale planetary scientist, told me. That’s because inclusions in the Martian meteorites contain gases that exactly match Mars’ known

Bits of Venus may be lurking on the moon, scientists suggest

Does Venus host alien life? That’s the big question after a recent study spotted phosphine — a gas with possible biological origins — in the planet’s clouds. We won’t have answers until further investigation, but clues to the planet’s history of habitability could be closer than expected.



NASA created this computer-simulated global view of Venus' northern hemisphere. NASA/JPL


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NASA created this computer-simulated global view of Venus’ northern hemisphere. NASA/JPL

Yale University astronomers Samuel Cabot and Gregory Laughlin said we should look to the moon for a peek into Venus’ past. They explained why in a paper accepted into the Planetary Science Journal this month.

The study suggests “asteroids and comets slamming into Venus may have dislodged as many as 10 billion rocks and sent them into an orbit that intersected with Earth and Earth’s moon,” Yale said in a statement. These impacts were more common billions of years ago, meaning bits of ancient Venus could remain as well-preserved meteorites on the lunar surface. 



NASA created this computer-simulated global view of the northern hemisphere of Venus.


© CNET

NASA created this computer-simulated global view of the northern hemisphere of Venus.


Venus is currently an inhospitable place with a toxic atmosphere. It’s the hottest planet in our solar system and is experiencing what NASA calls “a runaway greenhouse effect.” But it wasn’t always like this. Venus may have had oceans and even been habitable for life as recently as 700 million years ago.

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We may not have to wait too terribly long to bring new moon rocks back to Earth for the first time since the 1970s. NASA is encouraging private companies to launch sample collection missions and has its own ambitious plans to return humans to the moon in 2024.

Chemical analysis of moon rocks could tell us if they’re original parts of the moon or meteorites from elsewhere. 

“An ancient fragment of Venus would contain a wealth of information,” Laughlin said. “Venus’ history is closely tied to important topics in planetary science, including the past influx of asteroids and comets, atmospheric histories of the inner planets, and the abundance of liquid water.”   

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