Posts Tagged ‘planetary’

Mars_NASA

Mars [image credit: NASA]

Researchers say this could open the door to prediction of dust storms, which can seriously affect the solar panels of devices sent to investigate distant bodies like Mars. They also suggest such patterns may be common to all planetary atmospheres.
– – –
Annular modes explain much of the internal variability of Earth’s atmosphere but have never been identified as influential on other planets, says Sci-News.

On Earth, the regularity of storm systems in the middle latitudes is associated with what is called an annular mode — a variability in atmospheric flow that is unrelated to the cycle of seasons.

Annular modes affect the jet stream, precipitation, and cloud formations across the planet.

They explain up to one-third of the variability in wind-driven ‘eddies,’ including blizzards in New England and severe storm outbreaks in the Midwest.

In a new study, Yale University researchers Juan Lora and J. Michael Battalio found that annular modes on Titan and Mars are even more influential than they are on Earth.

(more…)

.

Escaping a planet’s gravity is supposed to be difficult, but some Martian dust does just that.

Spaceweather.com

July 6, 2021: Dust storms on Mars are bigger than we thought; they even spill into space. According to a recent paper in JGR Planets, Mars appears to be leaking dust, filling a huge volume of the inner solar system with gritty debris. You can see it with your naked eye. The bright triangle in this image from the Haleakalā Observatory in Hawaii is marsdust:

“A friend described it as blazing,” says Rob Ratkowski, who took the picture on Feb. 10th. “It was bright and very obvious.”

It’s called Zodiacal Light, and astronomers have long wondered what causes it. The usually faint triangle is sunlight scattered by dust in the plane of our solar system. The dust, it turns out, comes from Mars.

NASA’s Juno spacecraft flew through the dust cloud en route to Jupiter between 2011 and 2016. Dust grains smashed into Juno at about 10,000 mph…

View original post 225 more words

EarthspaceScientists previously proposed 26 million year cycles of mass extinctions, but this appears to correct the period. They suggest ‘cycles of activity in the Earth’s interior’ could be behind their new period, but then say: ‘However, similar cycles in the Earth’s orbit in space might also be pacing these events.’ Their study also says ‘a strong secondary signal occurs at a period 8.9 Myr’.
– – –
Geologic activity on Earth appears to follow a 27.5-million-year cycle, giving the planet a ‘pulse,’ according to a new study published in the journal Geoscience Frontiers. Phys.org reporting.

“Many geologists believe that geological events are random over time. But our study provides statistical evidence for a common cycle, suggesting that these geologic events are correlated and not random,” said Michael Rampino, a geologist and professor in New York University’s Department of Biology, as well as the study’s lead author.

Over the past five decades, researchers have proposed cycles of major geological events—including volcanic activity and mass extinctions on land and sea—ranging from roughly 26 to 36 million years.

But early work on these correlations in the geological record was hampered by limitations in the age-dating of geologic events, which prevented scientists from conducting quantitative investigations.

(more…)

Image credit: livescience.com

The problem is, the ‘wrong’ side is warmer than the other one. Enter Rodinia.
– – –
We’ve known for a long time that Earth’s fiery interior is destined to burn out in the distant future, although new research indicates that this process may be occurring faster on one side of the planet than the other, says IFL Science..

By analyzing the movement of continents and oceanic plates over the past 400 million years, researchers have determined that parts of the planet have remained more insulated than others, leading to an asymmetrical pattern of heat loss.

(more…)

Lagrange points in the Sun–Earth system (not to scale). A small object at L4 or L5 will hold its relative position [Credit: Xander89 @ Wikipedia]


More about Lagrange points here.
– – –
A recently discovered asteroid appears to be an Earth Trojan, orbiting a gravitationally stable area with only one other known occupant, says Sky & Telescope.

Trojans are asteroids gravitationally locked to stable Lagrange points either 60° ahead (L4) or behind (L5) the planets in their orbits around the Sun. 2020 XL5 was found around the L4 point.

Massive Jupiter has more than 9,000 Trojans.

In theory, Trojan orbits would be stable around every planet except Saturn, where Jupiter’s gravity pulls them away.

(more…)

Clouds on Mars [image credit: NASA]


Regarding the Earth’s equivalent Chandler wobble, Wikipedia says: ‘Since the Chandler wobble should die down in a matter of decades or centuries, there must be influences that continually re-excite it.’ Presumably the same will apply to Mars, but as relevant observations are all fairly recent no conclusion can be reached at present.
– – –
Spacecraft find that Mars oscillates 10 centimeters off its axis of rotation, says Eos.

In a first for a solar system body other than Earth, scientists have detected the Chandler wobble on Mars, a repeated movement of the poles on the surface of the planet away from its average axis of rotation.

The Chandler wobble arises when a rotating body isn’t a perfect sphere. This imbalance affects its spin.

The result is a wiggle resembling that of a swaying top as it loses speed, rather than the smooth spin of a perfectly balanced globe.

(more…)

Credit: earth.com


Greetings Earthlings, or should we say ‘habitable-zone-dwelling asteroid dodgers’? We even have the right amount of atmosphere — not too little (like Mars) or too much (like Venus), and the essential oxygen.
– – –
Pure chance is the reason that Planet Earth has stayed habitable for billions of years.

A new study has found that it’s nothing more than good luck that has kept our world full of life, reports I-news.

Scientists at the University of Southampton have carried out a mass simulation of climate evolution of 100,000 randomly generated planets.

Each planet was simulated 100 times with random climate-altering events occurring each time in order to see if habitable life could be sustained for three billion years like on Earth.

(more…)

Model dinosaur


The lead author of the study puts the blame on “the largest cataclysmic impacts and massive volcanism, perhaps sometimes working in concert.” The study says: ‘The correlations and similar cycles in marine and non-marine extinction episodes suggest a common cause’. Note: this is a follow-up to a 2015 study with the same lead author, also featured at the Talkshop.
– – –
Mass extinctions of land-dwelling animals—including amphibians, reptiles, mammals, and birds—follow a cycle of about 27 million years, coinciding with previously reported mass extinctions of ocean life, according to a new analysis published in the journal Historical Biology.

The study also finds that these mass extinctions align with major asteroid impacts and devastating volcanic outpourings of lava called flood-basalt eruptions—providing potential causes for why the extinctions occurred, reports Phys.org.

“It seems that large-body impacts and the pulses of internal Earth activity that create flood-basalt volcanism may be marching to the same 27-million-year drumbeat as the extinctions, perhaps paced by our orbit in the Galaxy,” said Michael Rampino, a professor in New York University’s Department of Biology and the study’s lead author.

(more…)


Another round of the enduring hexagon mystery.
– – –
With its dazzling system of icy rings, Saturn has been a subject of fascination since ancient times, says Phys.org.

Even now the sixth planet from the sun holds many mysteries, partly because its distance away makes direct observation difficult and partly because this gas giant (which is multiple times the size of our planet) has a composition and atmosphere, mostly hydrogen and helium, so unlike that of Earth.

Learning more about it could yield some insights into the creation of the solar system itself.

One of Saturn’s mysteries involves the massive storm in the shape of a hexagon at its north pole.

(more…)

Cyclones in Jupiter’s atmosphere [image credit: NASA]


At the south pole of Jupiter lurks a striking sight—even for a gas giant planet covered in colorful bands that sports a red spot larger than the Earth, says Phys.org.

Down near the south pole of the planet, mostly hidden from the prying eyes of humans, is a collection of swirling storms arranged in an unusually geometric pattern.

Since they were first spotted by NASA’s Juno space probe in 2019, the storms have presented something of a mystery to scientists.

The storms are analogous to hurricanes on Earth. However, on our planet, hurricanes do not gather themselves at the poles and twirl around each other in the shape of a pentagon or hexagon, as do Jupiter’s curious storms.

(more…)

Credit: NASA [click on image to enlarge]


The effects of relative proximity between these large moons seem to have been underrated. Not forgetting that Jupiter does have a big effect on Io, the closest Galilean moon to it.
– – –
Jupiter’s “ocean world” moons may have strong gravitational effects on each other, raising big tides in each others’ subsurface seas, a new study suggests [Space.com reporting].

Surprisingly, these moon-moon tidal forces might generate more heat in the satellites’ oceans than the gravitational tugs of giant Jupiter, study team members found.

“That’s kind of interesting, because Jupiter is the biggest mass in that system, so its tidal forces are much bigger than one moon on another,” lead author Hamish Hay, who performed the work while at the University of Arizona’s Lunar and Planetary Laboratory, said in a statement.

(more…)

Venus


The presence of sulphur in the atmosphere hinted at this.
– – –
A new study identified 37 recently active volcanic structures on Venus, reports Phys.org.

The study provides some of the best evidence yet that Venus is still a geologically active planet.

A research paper on the work, which was conducted by researchers at the University of Maryland and the Institute of Geophysics at ETH Zurich, Switzerland, was published in the journal Nature Geoscience on July 20, 2020.

“This is the first time we are able to point to specific structures and say ‘Look, this is not an ancient volcano but one that is active today, dormant perhaps, but not dead,'” said Laurent Montési, a professor of geology at UMD and co-author of the research paper. “This study significantly changes the view of Venus from a mostly inactive planet to one whose interior is still churning and can feed many active volcanoes.”

(more…)


Researchers now want to ‘understand both the processes that excite the waves and the processes that act to damp the waves.’
– – –
A ringing bell vibrates simultaneously at a low-pitched fundamental tone and at many higher-pitched overtones, producing a pleasant musical sound, says Phys.org.

A recent study, just published in the Journal of the Atmospheric Sciences by scientists at Kyoto University and the University of Hawaii at Mānoa, shows that the Earth’s entire atmosphere vibrates in an analogous manner, in a striking confirmation of theories developed by physicists over the last two centuries.

In the case of the atmosphere, the “music” comes not as a sound we could hear, but in the form of large-scale waves of atmospheric pressure spanning the globe and traveling around the equator, some moving east-to-west and others west-to-east.

Each of these waves is a resonant vibration of the global atmosphere, analogous to one of the resonant pitches of a bell.

The basic understanding of these atmospheric resonances began with seminal insights at the beginning of the 19th century by one of history’s greatest scientists, the French physicist and mathematician Pierre-Simon Laplace.

Research by physicists over the subsequent two centuries refined the theory and led to detailed predictions of the wave frequencies that should be present in the atmosphere. However, the actual detection of such waves in the real world has lagged behind the theory.

Now in a new study by Takatoshi Sakazaki, an assistant professor at the Kyoto University Graduate School of Science, and Kevin Hamilton, an Emeritus Professor in the Department of Atmospheric Sciences and the International Pacific Research Center at the University of Hawaii at Mānoa, the authors present a detailed analysis of observed atmospheric pressure over the globe every hour for 38 years.

The results clearly revealed the presence of dozens of the predicted wave modes.

Full article here.


This is easily shown from the 74 Jupiter-Saturn conjunctions in the period:
1 J-S = 19.865036 sidereal years = 19.865036*365.25636 days = 7255.8307
(7255.8307*74) / 365.259636 (anomalistic year) = 1469.99945 (1470)

So Earth reaches its perihelion with the Sun exactly 1470 times per 74 J-S.

Both numbers are even, so why is the Dansgaard-Oeschger event not at half the period?
The short answer is: Neptune.

(more…)


It now seems all planetary bodies can have magnetospheres, whether or not they have a significant magnetic field. This would also help to explain why Venus, with hardly any ‘protective’ magnetic field, has a much thicker atmosphere than Earth. Wikipedia might need an update.
– – –
Five years after NASA’s MAVEN spacecraft entered into orbit around Mars, data from the mission has led to the creation of a map of electric current systems in the Martian atmosphere, reports Phys.org.

“These currents play a fundamental role in the atmospheric loss that transformed Mars from a world that could have supported life into an inhospitable desert,” said experimental physicist Robin Ramstad of the University of Colorado, Boulder.

“We are now currently working on using the currents to determine the precise amount of energy that is drawn from the solar wind and powers atmospheric escape.” Ramstad is lead author of a paper on this research published May 25 in Nature Astronomy.

(more…)

Credit: NASA


This BBC link includes a video which shows the weakening of the magnetic field over the last 400 years (under ‘Magnetic flip’ sub-heading).
– – –
In an area stretching from Africa to South America, Earth’s magnetic field is gradually weakening, says Phys.org.

This strange behaviour has geophysicists puzzled and is causing technical disturbances in satellites orbiting Earth.

Scientists are using data from ESA’s Swarm constellation to improve our understanding of this area known as the ‘South Atlantic Anomaly.’

(more…)

Saturn’s hexagon


The ever-mysterious hexagon goes under the microscope, or telescope at least.

A rich variety of meteorological phenomena takes place in the extensive hydrogen atmosphere of Saturn, a world about 10 times the size of the Earth.

They help us to better understand similar features in the Earth’s atmosphere, says Phys.org.

Among Saturn’s atmospheric phenomena is the well-known “hexagon,” an amazing wave structure that surrounds the planet’s polar region.

(more…)

Image credit: NASA-ISS


Dust storms are common in the region, and sometimes bear resemblance to weather events on Mars, according to NASA.
– – –
A surging dust storm and trailing dust cloud captured an astronaut’s attention as the International Space Station (ISS) was passing over South America, says NASA’s Earth Observatory.

Dust storms are common in Patagonia and familiar for people in Comodoro Rivadavia, a coastal city in southern Argentina.

The primary source of dust is Lago Colhué Huapí, a shallow lake adjacent to the much deeper Lago Musters.

(more…)

Magnetic North on the move [credit: ESA]


They have a go at doing so, anyway. To make it more complicated, the South Magnetic Pole is also moving, but at a much lesser rate.

European scientists think they can now describe with confidence what’s driving the drift of the North Magnetic Pole, says BBC News.

It’s shifted in recent years away from Canada towards Siberia.

And this rapid movement has required more frequent updates to navigation systems, including those that operate the mapping functions in smartphones.

A team, led from Leeds University, says the behaviour is explained by the competition of two magnetic “blobs” on the edge of the Earth’s outer core.

(more…)

Image credit: naturalnavigator.com


We’re told: ‘They refer to what they’ve found as ANTS, for Active Nearside Tectonic System’, which is ‘a mysterious system of tectonic features (ridges and faults) on the lunar nearside, unrelated to both lava-filled basins and other young faults that crisscross the highlands.’ Tectonic activity on one side only sounds a bit unlikely somehow, but what about tidal disturbance from Earth? We know it works the other way round: the Moon causes tides on Earth. Of course the Moon is tidally locked to Earth, hence the term ‘nearside’.
– – –
Researchers have discovered a system of ridges spread across the nearside of the Moon topped with freshly exposed boulders, reports Phys.org.

The ridges could be evidence of active lunar tectonic processes, the researchers say, possibly the echo of a long-ago impact that nearly tore the Moon apart.

“There’s this assumption that the Moon is long dead, but we keep finding that that’s not the case,” said Peter Schultz, a professor in Brown University’s Department of Earth, Environmental and Planetary Sciences and co-author of the research, which is published in the journal Geology.

“From this paper it appears that the Moon may still be creaking and cracking—potentially in the present day—and we can see the evidence on these ridges.”

(more…)