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By NASA
Discovery Alert: Watch the Synchronized Dance of a 6-Planet System
The discovery: Six planets orbit their central star in a rhythmic beat, a rare case of an “in sync” gravitational lockstep that could offer deep insight into planet formation and evolution.
Key facts: A star smaller and cooler than our Sun hosts a truly strange family of planets: six “sub-Neptunes” – possibly smaller versions of our own Neptune – moving in a cyclic rhythm. This orbital waltz repeats itself so precisely it can be readily set to music.
This animation shows six “sub-Neptune” exoplanets in rhythmic orbits around their star – with a musical tone as each planet passes a line drawn through the system. The line is where the planets cross in front of (transit) their star from Earth’s perspective. In these rhythms, known as “resonance,” the innermost planet makes three orbits for every two of the next planet out. Among the outermost planets, a pattern of four orbits for every three of the next planet out is repeated twice. Animation credit: Dr. Hugh Osborn, University of Bern Details: While multi-planet systems are common in our galaxy, those in a tight gravitational formation known as “resonance” are observed by astronomers far less often. In this case, the planet closest to the star makes three orbits for every two of the next planet out – called a 3/2 resonance – a pattern that is repeated among the four closest planets.
Among the outermost planets, a pattern of four orbits for every three of the next planet out (a 4/3 resonance) is repeated twice. And these resonant orbits are rock-solid: The planets likely have been performing this same rhythmic dance since the system formed billions of years ago. Such reliable stability means this system has not suffered the shocks and shakeups scientists might typically expect in the early days of planet formation – smash-ups and collisions, mergers and breakups as planets jockey for position. And that, in turn, could say something important about how this system formed. Its rigid stability was locked in early; the planets’ 3/2 and 4/3 resonances are almost exactly as they were at the time of formation. More precise measurements of these planets’ masses and orbits will be needed to further sharpen the picture of how the system formed.
Fun facts: The discovery of this system is something of a detective story. The first hints of it came from NASA’s TESS (the Transiting Exoplanet Survey Satellite), which tracks the tiny eclipses – the “transits” – that planets make as they cross the faces of their stars. Combining the TESS measurements, made in separate observations two years apart, revealed an assortment of transits for the host star, called HD 110067. But it was difficult to distinguish how many planets they represented, or to pin down their orbits.
Eventually, astronomers singled out the two innermost planets, with orbital periods – “years” – of 9 days for the closest planet, 14 days for the next one out. A third planet, with a year about 20 days long, was identified with the help of data from CHEOPS, The European Space Agency’s CHaracterising ExOPlanets Satellite.
Then the scientists noticed something extraordinary. The three planets’ orbits matched what would be expected if they were locked in a 3/2 resonance. The next steps were all about math and gravity. The science team, led by Rafael Luque of the University of Chicago, worked through a well-known list of resonances that potentially could be found in such systems, trying to match them to the remaining transits that had been picked up by TESS. The only resonance chain that matched up suggested a fourth planet in the system, with an orbit about 31 days long. Two more transits had been seen, but their orbits remained unaccounted for because they were only single observations (more than one transit observation is needed to pin down a planet’s orbit). The scientists again ran through the list of possible orbits if there were two additional, outer planets that fit the expected chain of resonances across the whole system. The best fit they found: a fifth planet with a 41-day orbit, and a sixth just shy of 55.
At this point the science team almost hit a dead end. The slice of the TESS observations that had any chance of confirming the predicted orbits of the two outer planets had been set aside during processing. Excessive light scattered through the observation field by Earth and the Moon seemed to make them unusable. But not so fast. Scientist Joseph Twicken, of the SETI Institute and of the NASA Ames Research Center, took notice of the scattered light problem. He knew that scientist David Rapetti, also of Ames and of the Universities Space Research Association, happened to be working on a new computer code to recover transit data thought to be lost because of scattered light. At Twicken’s suggestion, Rapetti applied his new code to the TESS data. He found two transits for the outer planets – exactly where the science team led by Luque had predicted.
The discoverers: An international team of researchers led by Rafael Luque, of the University of Chicago, published a paper online on the discovery, “A resonant sextuplet of sub-Neptunes transiting the bright star HD 110067,” in the journal Nature on Nov. 29.
Tracing a link between two neighbour planet at regular time interval along their orbits, creates a pattern unique to each couple. The six planets of the HD110067 system create together a mesmerising geometric pattern due to their resonance-chain. Credit: Thibaut Roger/NCCR PlanetS, CC BY-NC-SA 4.0 View the full article
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By USH
A fascinating and unique structure spanning 4 kilometers in length has been discovered on Mars by Myytinkertojat Media and shared by Suspicious0bservers.
While conventional geological perspectives might attribute it to a natural formation, such as a ridge or mountain shaped by specific erosion patterns over the planet's history, this particular structure stands out. Unlike numerous other straight and vertical formations on Mars, it defies the natural order and it does not fit with the surrounding landscape.
Rather than mirroring the typical traits of natural features, this structure bears a striking resemblance to a constructed wall. Notably, even there is a reflection of light bouncing off the structure onto the Martian surface.
This discovery adds to a growing list of anomalies on Mars that defy conventional explanations. Could it be conceivable that this intriguing structure represents the remnants of an ancient wall, perhaps constructed by intelligent beings who once inhabited Mars before a catastrophic event made the planet uninhabitable?
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By NASA
9 Min Read Temperatures Across Our Solar System
An illustration of our solar system. Planets and other objects are not to scale. Credits:
NASA What’s the weather like out there? We mean waaaay out there in our solar system – where the forecast might not be quite what you think.
Let’s look at the mean temperature of the Sun, and the planets in our solar system. The mean temperature is the average temperature over the surface of the rocky planets: Mercury, Venus, Earth, and Mars. Dwarf planet Pluto also has a solid surface. But since the gas giants don’t have a surface, the mean is the average temperature at what would be equivalent at sea level on Earth.
An illustration of planets in our solar system showing their mean temperatures. Planets and dwarf planet Pluto are not to scale. NASA Let’s start with our Sun. You already know the Sun is hot. OK, it’s extremely hot! But temperatures on the Sun also are a bit puzzling.
An image of the Sun taken Oct. 30, 2023, by NASA’s Solar Dynamics Observatory. NASA/SDO The hottest part of the Sun is its core, where temperatures top 27 million°F (15 million°C). The part of the Sun we call its surface – the photosphere – is a relatively cool 10,000° F (5,500°C). In one of the Sun’s biggest mysteries, the Sun’s outer atmosphere, the corona, gets hotter the farther it stretches from the surface. The corona reaches up to 3.5 million°F (2 million°C) – much, much hotter than the photosphere.
So some temperatures on the Sun are a bit upside down. How about the planets? Surely things are cooler on the planets that are farther from the Sun.
Well, mostly. But then there’s Venus.
As it sped away from Venus, NASA’s Mariner 10 spacecraft captured this seemingly peaceful view of a planet the size of Earth, wrapped in a dense, global cloud layer. But, contrary to its serene appearance, the clouded globe of Venus is a world of intense heat, crushing atmospheric pressure and clouds of corrosive acid. NASA/JPL-Caltech Venus is the second closest planet to the Sun after Mercury, with an average distance from the Sun of about 67 million miles (108 million kilometers). It takes sunlight about six minutes to travel to Venus.
Venus also is Earth’s closest neighbor and is similar in size. It has even been called Earth’s twin. But Venus is shrouded in clouds and has a dense atmosphere that acts as a greenhouse and heats the surface to above the melting point of lead. It has a mean surface temperature of 867°F (464°C).
So Venus – not Mercury – is the hottest planet in our solar system. Save that bit of info for any future trivia contests.
Maybe Venus is hotter, but Mercury is the closest planet to the Sun. Surely it gets hot, too?
Mercury as seen from NASA’s MESSENGER, the first spacecraft to orbit Mercury. NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington Mercury is about 36 million miles (57 million kilometers) from the Sun. From this distance, it takes sunlight about three minutes to travel to Mercury. Even though it’s sitting right next to the Sun – relatively speaking – Mercury gets extremely cold at night. It has a mean surface temperature of 333°F (167°C). Daytime temperatures get much hotter than the mean, and can reach highs of 800°F (430°C). But without an atmosphere thick enough to hold in the heat at night, temperatures can dip as low as -290°F (-180°C).
Ahhh, Earth. We know about the weather here, right? Even Earth has some temperatures you may not have heard about.
An image of Earth from the Deep Space Climate Observatory, or DSCOVR. NASA Earth is an average of 93 million miles (150 million kilometers) from the Sun. It takes about eight minutes for light from the Sun to reach our planet.
Our homeworld is a dynamic and stormy planet with everything from clear, sunny days, to brief rain showers, to tornados, to raging hurricanes, to blizzards, and dust storms. But in spite of its wide variety of storms – Earth generally has very hospitable temperatures compared to the other planets. The mean surface temperature on Earth is 59°F (15°C). But Earth days have some extreme temperatures. According to NOAA, Death Valley holds the record for the world’s highest surface air temperature ever recorded on Earth: 134°F (56.7°C) observed at Furnace Creek (Greenland Ranch), California, on July 10, 1913. Earth’s lowest recorded temperature was -128.6°F (89.2°C) at Vostok Station, Antarctica, on July 21, 1983, according to the World Meteorological Organization.
NASA missions have found lots of evidence that Mars was much wetter and warmer, with a thicker atmosphere, billions of years ago. How about now?
Side-by-side animated images show how a 2018 global dust storm enveloped the Red Planet. The images were taken by NASA’s Mars Reconnaissance Orbiter (MRO). NASA/JPL-Caltech/MSSS Mars is an average distance of 142 million miles (228 million kilometers) from the Sun. From this distance, it takes about 13 minutes for light to travel from the Sun to Mars.
The median surface temperature on Mars is -85°F (-65°C). Because the atmosphere is so thin, heat from the Sun easily escapes Mars. Temperatures on the Red Planet range from the 70s°F (20s°C) to -225°F (-153°C). Occasionally, winds on Mars are strong enough to create dust storms that cover much of the planet. After such storms, it can be months before all of the dust settles.
Two NASA rovers on Mars have weather stations. You can check the daily temps at their locations:
Mars Weather Report From Perseverance Curiosity Daily Weather Report The ground temperature around the Perseverance rover ranges from about -136°F to 62°F (-93°C to 17°C). The air temperature near the surface ranges from about -118°F to 8°F (-83°C to -13°C).
As planets move farther away from the Sun, it really cools down fast! Since gas giants Jupiter and Saturn don’t have a solid surface, temperatures are taken from a level in the atmosphere equal in pressure to sea level on Earth. The same goes for the ice giants Uranus and Neptune.
NASA’s Juno spacecraft took this image during a flyby of Jupiter. This view highlights Jupiter’s most famous weather phenomenon, the persistent storm known as the Great Red Spot. Citizen scientist Kevin M. Gill created this image using data from the spacecraft’s JunoCam imager. Enhanced image by Kevin M. Gill (CC-BY) based on images provided courtesy of NASA/JPL-Caltech/SwRI/MSSS Jupiter’s stripes and swirls are beautiful, but they are actually cold, windy clouds of ammonia and water, floating in an atmosphere of hydrogen and helium. The planet’s iconic Great Red Spot is a giant storm bigger than Earth that has raged for hundreds of years. The mean temperature on Jupiter is -166°F (-110°C).
Jupiter is an average distance of 484 million miles (778 million kilometers) from the Sun. From this distance, it takes sunlight 43 minutes to travel from the Sun to Jupiter. Jupiter has the shortest day in the solar system. One day on Jupiter takes only about 10 hours (the time it takes for Jupiter to rotate or spin around once), and Jupiter makes a complete orbit around the Sun (a year in Jovian time) in about 12 Earth years (4,333 Earth days).
Jupiter’s equator is tilted with respect to its orbital path around the Sun by just 3 degrees. This means the giant planet spins nearly upright and does not have seasons as extreme as other planets do.
As we keep moving out into the solar system, we come to Saturn – the sixth planet from the Sun and the second largest planet in our solar system. Saturn orbits the Sun from an average distance of 886 million miles (1.4 billion kilometers). It takes sunlight 80 minutes to travel from the Sun to Saturn.
This series of images from NASA’s Cassini spacecraft shows the development of the largest storm seen on Saturn since 1990. These true-color and composite near-true-color views chronicle the storm from its start in late 2010 through mid-2011, showing how the distinct head of the storm quickly grew large but eventually became engulfed by the storm’s tail. NASA/JPL-Caltech/Space Science Institute Like fellow gas giant Jupiter, Saturn is a massive ball made mostly of hydrogen and helium and it doesn’t have a true surface. The mean temperature is -220°F (-140°C).
In addition to the bone-chilling cold, the winds in the upper atmosphere of Saturn reach 1,600 feet per second (500 meters per second) in the equatorial region. In contrast, the strongest hurricane-force winds on Earth top out at about 360 feet per second (110 meters per second). And the pressure – the same kind you feel when you dive deep underwater – is so powerful it squeezes gas into a liquid.
This colorful movie made with images from NASA’s Cassini spacecraft is the highest-resolution view of the unique six-sided jet stream at Saturn’s north pole known as “the hexagon.” NASA/JPL-Caltech/SSI/Hampton University Saturn’s north pole has an interesting atmospheric feature – a six-sided jet stream. This hexagon-shaped pattern was first noticed in images from the Voyager I spacecraft and was more closely observed by the Cassini spacecraft. Spanning about 20,000 miles (30,000 kilometers) across, the hexagon is a wavy jet stream of 200-mile-per-hour winds (about 322 kilometers per hour) with a massive, rotating storm at the center. There is no weather feature like it anywhere else in the solar system.
Crane your neck to the side while we go check out the weather on Uranus, the sideways planet.
This is an image of the planet Uranus taken by the spacecraft Voyager 2 in 1986. NASA/JPL-Caltech The seventh planet from the Sun with the third largest diameter in our solar system, Uranus is very cold and windy. It has a mean temperature of -320°F (-195°C). Uranus rotates at a nearly 90-degree angle from the plane of its orbit. This unique tilt makes Uranus appear to spin sideways, orbiting the Sun like a rolling ball. And like Saturn, Uranus has rings. The ice giant is surrounded by 13 faint rings and 27 small moons.
Now we move on to the last major planet in our solar system – Neptune. What’s the weather like there? Well you would definitely need a windbreaker if you went for a visit. Dark, cold, and whipped by supersonic winds, giant Neptune is the eighth and most distant major planet orbiting our Sun. The mean temperature on Neptune is -330°F (-200°C).
And not to be outdone by Jupiter and its Great Red Spot, Neptune has the Great Dark Spot – and Scooter. Yep, Scooter.
Voyager 2 photographed these features on Neptune in 1989. NASA/JPL-Caltech This photograph of Neptune was created from two images taken by NASA’s Voyager 2 spacecraft in August 1989. It was the first and last time a spacecraft came close to Neptune. The image shows three of the features that Voyager 2 monitored. At the north (top) is the Great Dark Spot, accompanied by bright, white clouds that undergo rapid changes in appearance. To the south of the Great Dark Spot is the bright feature that Voyager scientists nicknamed “Scooter.” Still farther south is the feature called “Dark Spot 2,” which has a bright core.
More than 30 times as far from the Sun as Earth, Neptune is not visible to the naked eye. In 2011, Neptune completed its first 165-year orbit of the Sun since its discovery.
That wraps up forecasting for the major planets.
But there is one more place we need to check out. Beyond Neptune is a small world, with a big heart – dwarf planet Pluto.
New Horizons scientists use enhanced color images to detect differences in the composition and texture of Pluto’s surface. NASA/JHUAPL/SwRI With a mean surface temperature of -375°F (-225°C), Pluto is considered too cold to sustain life. Pluto’s interior is warmer, however, and some think there may be an ocean deep inside.
From an average distance of 3.7 billion miles (5.9 billion kilometers) away from the Sun, it takes sunlight 5.5 hours to travel to Pluto. If you were to stand on the surface of Pluto at noon, the Sun would be 1/900 the brightness it is here on Earth. There is a moment each day near sunset here on Earth when the light is the same brightness as midday on Pluto.
So the next time you’re complaining about the weather in your spot here on Earth, think about Pluto and all the worlds in between.
Keep Exploring Discover More Topics From NASA
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