Posts Tagged ‘planetary’

A new tweak to tidal theory is proposed. The research team hopes that ‘understanding continental configurations and tidal strengths will impact the development of climate models’.

Daily tides are driven primarily by Earth’s rotation and the gravitational force of the moon on oceans, says Earth magazine.

However, in a new study in Geophysical Research Letters, researchers suggest that tidal magnitudes are also influenced, on longer timescales, by the size and shape of the ocean basins, and are therefore driven by plate tectonics.

Plate tectonics gives rise to the formation of supercontinents — massive aggregations of continental lithosphere — which form and break apart in cycles that last about 400 million to 500 million years. With the breakup of the last supercontinent, Pangea, about 180 million years ago, and the projected formation of a new supercontinent, known as Aurica, in about 200 million years, Earth is currently in the middle of a supercontinent cycle.

Because the size and shape of ocean basins impact ocean circulation and tides, researchers led by Mattias Green, a physical oceanographer at Bangor University in England, hypothesized that tides may be linked to the supercontinent cycle in a so-called supertidal cycle.

Current tides, particularly those in the North Atlantic, are very large, Green’s team noted because of tidal resonance, which occurs when ocean basins and continental shelves reinforce and amplify the natural oscillation of tides as they sweep back and forth across oceans. “So the tides are larger at present because the continents are configured the way they are.”

To model Earth’s future oceanic tides, the researchers used predictions of continental configurations for the next 250 million years, through when Aurica is predicted to form. Ocean basin size was the main factor considered in the modeling, but the team also accounted for the moon’s gravitational pull on the oceans, Earth’s axial tilt, and simplified ocean bathymetries for future plate tectonic reconstructions.

Simplification of these fine details does affect the team’s modeling, notes David Waltham, a mathematical geologist at the Royal Holloway University of London, who was not involved in the study. But the simplifications used likely do not change the overall results, he adds.

Green and his colleagues reported that global tides are likely to increase over the next 50 million years “due to an enhanced tide in the North Atlantic and Pacific at 25 million years, followed by a very large Pacific tide at 50 million years.”

Continued here.

Saturn’s north polar vortex and hexagon along with its expansive rings. The hexagon is wider than two Earths [image credit: NASA]

Another case of observing something that wasn’t thought possible. As the report notes: ‘The presence of a hexagon way up in Saturn’s northern stratosphere, hundreds of kilometres above the clouds, suggests that there is much more to learn about the dynamics at play in the gas giant’s atmosphere.’

The long-lived international Cassini mission has revealed a surprising feature emerging at Saturn’s northern pole as it nears summertime: a warming, high-altitude vortex with a hexagonal shape, akin to the famous hexagon seen deeper down in Saturn’s clouds.

This suggests that the lower-altitude hexagon may influence what happens up above, and that it could be a towering structure spanning hundreds of kilometres in height, reports


Credit: NASA

Temporary weather effects and more. For more background, there are several extra links in the original ScienceNews article.

A year after the total solar eclipse of 2017, scientists are still pondering the mysteries of the sun.

It’s been a year since the total solar eclipse of August 21, 2017, captured millions of imaginations as the moon briefly blotted out the sun and cast a shadow that crisscrossed the United States from Oregon to South Carolina.

“It was an epic event by all measures,” NASA astrophysicist Madhulika Guhathakurta told a meeting of the American Geophysical Union in New Orleans in December. One survey reports that 88 percent of adults in the United States — some 216 million people — viewed the eclipse either directly or electronically.


Ring of Fire earthquake zone [image credit: BBC]

The understanding of the processes may be lacking, but the evidence is there according to researchers.

New research shows that a big earthquake can not only cause other quakes, but large ones, and on the opposite side of the Earth, reports ScienceDaily.

The findings, published today in Scientific Reports, are an important step toward improved short-term earthquake forecasting and risk assessment.


Very Large Array, New Mexico [image credit: NASA]

This was ‘the first radio detection and the first measurement of the magnetic field of a possible planetary mass object beyond our Solar System.’ It’s even bigger than Jupiter. Plenty of puzzles for scientists to investigate.

Astronomers have used the VLA to detect a possible planetary-mass object with a surprisingly powerful magnetic field some 20 light-years from Earth.

It can help scientists better understand magnetic processes on stars and planets, says the National Radio Astronomy Observatory.

Astronomers using the National Science Foundation’s Karl G. Jansky Very Large Array
(VLA) have made the first radio-telescope detection of a planetary-mass object beyond our Solar System. The object, about a dozen times more massive than Jupiter, is a surprisingly strong magnetic powerhouse and a “rogue,” traveling through space unaccompanied by any parent star.



The apparent length of day on Venus (116.75 days) is nothing like its rotation time (~243 days), due to its retrograde spin. It can be stated as the time in which the sum of the number of Venus orbits (~0.52) and spins (~0.48) in the period equals 1.

As ScienceNewsforStudents reports, the thick atmosphere on Venus can change by a few minutes every day how long it takes the planet to rotate.

Time gets tricky on Venus. The planet has extremely thick air, which flows much more rapidly than the rate at which the solid planet spins.

As that thick atmosphere pushes against the planet’s mountains, it can change how quickly Venus spins, scientists now report.


Vertical line shows planetary conjunction with the Sun [credit: Wikipedia]

Numerous studies have found evidence of an apparently regular and significant climate event every 1,470 years (on average), which seems to show up most clearly in glacial periods. They speak of a ‘robust 1,470-year response time’, ‘a precise clock’, ‘abrupt climate change’ and so forth.

However they also say things like: ‘The origin of this regular pacing…remains a mystery.’

A couple of example studies here:
Possible solar origin of the 1,470-year glacial climate cycle demonstrated in a coupled model (2005)

Timing of abrupt climate change: A precise clock (2003)
– – –
Now we can relate this to the half period of the Jupiter-Saturn (J-S) conjunction cycle, i.e. one inferior or superior conjunction, as explained at Wikipedia.

The average J-S half-period is 9.932518 years.
The nearest harmonic to that period in Earth years is 10.
1470 = 148 * J-S/2
1470 = 147 * 10y
148 – 147 = 1 Dansgaard-Oeschger cycle

We find also that Jupiter, Saturn and Neptune conjunctions are such that:
148 * J-S/2 = 74 J-S = 41 S-N = 115 J-N = 1,470 years. [74 + 41 = 115]

Therefore 3 of the 4 major planets have a 1,470 year conjunction cycle.
(Planetary data from JPL @ NASA here)

So that’s the concept.
– – –
The graphics below are from Carsten Arnholm’s Solar Simulator software tool.
The interval between left and right sides is 1,470 years (May 501 – May 1971).

Each one shows a Jupiter, Neptune and Earth syzygy with Saturn opposite.
Note the similarity of the positions (red lines cross at the solar system barycentre).

Credit: [click to enlarge]

This is on similar lines to the ongoing studies of Nikolov & Zeller, featured here at the Talkshop on several occasions. The ‘standard’ tropopause pressure of ~0.1 bar is an interesting factor.

By looking at the temperature of every planet with sufficient atmospheres, we see temps rise along with atmospheric pressure, and not from a trace gas, says Alan Siddons at ClimateChangeDispatch.

Early in the 19th century, scientists began to speculate that the Earth, surrounded by the frigid vacuum of space, was habitable because its atmosphere contained special molecules like CO₂ and water vapor, molecules that can absorb heat rays emanating from the Earth and thereby trap its heat.

That the Earth was warmer than one might expect was apparently confirmed when Kirchhoff’s blackbody concept was adopted.


Arizona, USA

Amazing what can be gleaned from a 1,700 feet long rock core.
H/T Ian Wilson

Every 405,000 years, gravitational tugs from Jupiter and Venus slightly elongate Earth’s orbit, an amazingly consistent pattern that has influenced our planet’s climate for at least 215 million years and allows scientists to more precisely date geological events like the spread of dinosaurs, according to a Rutgers-led study.

The findings are published online today in the Proceedings of the National Academy of Sciences, reports ScienceDaily.


Screenshot from NASA video

There’s the usual speculative talk of exotic materials, mysterious dynamos and so forth, but the probe is delivering plenty of data for scientists to analyse and ponder over.

When NASA’s Juno spacecraft recently flew over the poles of Jupiter, researchers were astonished, as if they had never seen a giant planet before, says

And in a sense they hadn’t.


A montage of Uranus’ large moons and one smaller moon: from left to right Puck, Miranda, Ariel, Umbriel, Titania and Oberon. Size proportions are correct. [image credit: Vzb83 @ Wikipedia (from originals taken by NASA’s Voyager 2)]

The five major moons of Uranus in ascending distance from the planet are:
Miranda, Ariel, Umbriel, Titania and Oberon

Of these, the first three exhibit a synodic resonance similar to that of Jupiter’s Galilean moons, as we showed here:
Why Phi? – the resonance of Jupiter’s Galilean moons

Quoting from that post:
The only exact ratio is between the synodic periods which is 3:2:1.
It isn’t necessary to have an exact 4:2:1 orbit ratio in order to get a 3:2:1 synodic ratio.


Jupiter’s ‘Great Red Spot’ [image credit: NASA]

It seems to be turning into the not-so-great orange spot. Could this be a feature of climate change Jupiter-style?

Though once big enough to swallow three Earths with room to spare, Jupiter’s Great Red Spot has been shrinking for a century and a half, says Astronomy Now. Nobody is sure how long the storm will continue to contract or whether it will disappear altogether.

A new study suggests that it hasn’t all been downhill, though. The storm seems to have increased in area at least once along the way, and it’s growing taller as it gets smaller.


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

Octagon and pentagon (8:5) shapes at the poles, with groups of cyclones in a 9:6 (= 3:2) polar ratio. Fascinating.

Jupiter’s poles are blanketed by geometric clusters of cyclones and its atmosphere is deeper than scientists suspected, says

These are just some of the discoveries reported by four international research teams Wednesday, based on observations by NASA’s Juno spacecraft circling Jupiter.

One group uncovered a constellation of nine cyclones over Jupiter’s north pole and six over the south pole. The wind speeds exceed Category 5 hurricane strength in places, reaching 220 mph (350 kph).

The massive storms haven’t changed position much—or merged—since observations began.


Giant planets of the solar system [image credit:]

This post on the ice giants Uranus and Neptune follows on from this one:
Why Phi? – Jupiter, Saturn and the inner solar system

The main focus will be on Uranus. A planetary conjunction of three bodies (e.g. two planets and the Sun, in line) is also known as a syzygy.

Here’s the notation for the table shown below:
J-S = Jupiter-Saturn conjunctions
S-U = Saturn-Uranus conjunctions
U-N = Uranus-Neptune conjunctions

Each of the columns: U, S-U, J-S shows a Fibonacci progression.

Accuracy of best match is between 99.965% and 99.991%.

Quoting Wikipedia: ‘The mathematics of the golden ratio and of the Fibonacci sequence are intimately interconnected.’
The Greek letter φ (phi) represents the golden ratio.


Image credit:

But amplitude variations in the hum did not correlate with the seasons as once thought.

Scientists finally capture hum coming from the centre of the Earth, reports GeologyIn.

Although we like to think we know everything – and technology has advanced so much we practically have the answer to everything we don’t know at our fingertips – there are still plenty of mysteries left to solve.

For the past few decades, something has been becoming increasingly clear: Earth constantly hums, even though we can’t hear it.


The GOLD mission to learn more about the Earth’s ionosphere ran into comms problems after launch yesterday and may take longer than expected to reach its required orbit height. NASA’s own publicity says: “Just like an infrared camera allows you to see how temperatures change with different colors, GOLD images ultraviolet light to provide a map of the Earth that reveals how temperature and atmospheric composition change by location”.

NASA has reported that despite a glitch within minutes of its GOLD mission launch, the satellite is communicating with control systems, reports the Indian Express.

The aim of the Global-scale Observations of the Limb and Disk, or GOLD, mission is to study the dynamic region where space and Earth’s uppermost atmosphere meet.


Exoplanet – NASA impression

YZ Ceti is a recently discovered star with three known planets (b,c and d) orbiting very close to it. Although some types of mean motion resonance, or near resonance, are quite common e.g. 2:1 or 3:2 conjunction ratios, this one is a bit different.

The orbit periods in days are:
YZ Ceti b = 1.96876 d
YZ Ceti c = 3.06008 d
YZ Ceti d = 4.65627 d

This gives these conjunction periods:
c-d = 8.9266052 d
b-c = 5.5204368 d
b-d = 3.4109931 d
(Note the first two digits on each line.)

Nearest matching period:
34 c-d = 303.50457 d
55 b-c = 303.62403 d
89 b-d = 303.57838 d

34,55 and 89 are Fibonacci numbers.
Therefore the conjunction ratios are linked to the golden ratio (Phi).

Phi = 1.618034
(c-d) / (b-c) = 1.6170106
(b-c) / (b-d) = 1.618425

Data source:

Uranus [image credit: NASA]

One of the two processes involved is “due to high-speed particles from outside the solar system, known as galactic cosmic rays, bombarding the atmosphere and influencing the formation of clouds”, reports If so, it looks like further evidence for the Svensmark hypothesis.

Changes in solar activity influence the colour and formation of clouds around the planet, researchers at Oxford and Reading universities found.

The icy planet is second furthest from the sun in the solar system and takes 84 Earth years to complete a full orbit – one Uranian year.

The researchers found that, once the planet’s long and strange seasons are taken into account, it appears brighter and dimmer over a cycle of 11 years. This is the regular cycle of solar activity which also affects sun spots.


Jupiter [image credit: NASA]

The caption to the explanatory video says: ‘When scientists look at Jupiter’s upper atmosphere in infrared light, they see the region above the equator heating and cooling over a roughly four-year cycle’.

Speeding through the atmosphere high above Jupiter’s equator is an east-west jet stream that reverses course on a schedule almost as predictable as a Tokyo train’s, says Now, a NASA-led team has identified which type of wave forces this jet to change direction.

Similar equatorial jet streams have been identified on Saturn and on Earth, where a rare disruption of the usual wind pattern complicated weather forecasts in early 2016.

The new study combines modeling of Jupiter’s atmosphere with detailed observations made over the course of five years from NASA’s Infrared Telescope Facility, or IRTF, in Hawai’i. The findings could help scientists better understand the dynamic atmosphere of Jupiter and other planets, including those beyond our solar system.


Star system has record eight exoplanets

Posted: December 14, 2017 by oldbrew in Astronomy, Astrophysics, News
Tags: ,

Kepler Space Telescope [credit: NASA]

The two nearest planets to the star Kepler-90 (90b and 90c) are very close to a 5:4 (i.e. first order) orbit ratio.

Nasa finds a distant star circled by eight planets, equal to the complement in our own Solar System, BBC News reports.

It’s the largest number of worlds ever discovered in a planetary system outside our own.

The star known as Kepler-90, is just a bit hotter and larger than the Sun; astronomers already knew of seven planets around it.

The newly discovered world is small enough to be rocky, according to scientists.