outer solar – Sinia Planeta http://sinia-planeta.com/ Wed, 09 Mar 2022 17:50:16 +0000 en-US hourly 1 https://wordpress.org/?v=5.9.3 https://sinia-planeta.com/wp-content/uploads/2021/10/icon-50-120x120.png outer solar – Sinia Planeta http://sinia-planeta.com/ 32 32 An Earth-like planet could be orbiting in the ‘habitable zone’ of a dead star https://sinia-planeta.com/an-earth-like-planet-could-be-orbiting-in-the-habitable-zone-of-a-dead-star/ Wed, 09 Mar 2022 15:00:57 +0000 https://sinia-planeta.com/an-earth-like-planet-could-be-orbiting-in-the-habitable-zone-of-a-dead-star/ Planetary debris, including some moon-sized objects, may hint at a rocky exoplanet in a stellar zombie’s habitable zone, according to a new study. The star in question is a white dwarf called WD1054-226, a cooling remnant of a star that has used up all the fuel in its core. If an exoplanet is confirmed in […]]]>

Planetary debris, including some moon-sized objects, may hint at a rocky exoplanet in a stellar zombie’s habitable zone, according to a new study.

The star in question is a white dwarf called WD1054-226, a cooling remnant of a star that has used up all the fuel in its core. If an exoplanet is confirmed in the system, it would be a breakthrough for white dwarf science, the researchers noted in a statement. Only one other planet has been discovered to date orbiting a white dwarf. This planet, however, is a gas giant, a planet similar to Jupiter, and not near the habitable zone (generally defined as where liquid water can exist on the surface of a rocky planet).

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A massive comet crossing the solar system is 15 times higher than Mount Everest https://sinia-planeta.com/a-massive-comet-crossing-the-solar-system-is-15-times-higher-than-mount-everest/ Mon, 14 Feb 2022 09:09:48 +0000 https://sinia-planeta.com/a-massive-comet-crossing-the-solar-system-is-15-times-higher-than-mount-everest/ New Delhi: A giant comet, one of the largest ever detected, is traveling through our solar system at an alarming speed. The comet, called Bernardinelli-Bernstein, has a surface equivalent diameter of about 137 kilometers, according to a new study. The study, conducted by French and Spanish researchers, will be published in the journal, Astronomy and […]]]>

New Delhi: A giant comet, one of the largest ever detected, is traveling through our solar system at an alarming speed. The comet, called Bernardinelli-Bernstein, has a surface equivalent diameter of about 137 kilometers, according to a new study.

The study, conducted by French and Spanish researchers, will be published in the journal, Astronomy and astrophysics.

Bernardinelli-Bernstein is 15 times bigger than Mount Everest

With a diameter of about 137 kilometers, the comet is 15 times higher than Mount Everest, which has an altitude of 8,848.86 meters, or about 8.85 kilometers. The summit of Mount Everest is one of the highest points on Earth.

ALSO READ: Scientists watch DiCaprio’s ‘Don’t Look Up’ on Netflix. Here’s what they say about his messages on climate change

According to an article published by indy100, an online sister newspaper to the British online newspaper The Independent, the comet is almost unfathomable and difficult to understand, and is six times larger than the comet that caused the extinction of the dinosaurs a while ago. about 65 million years old. .

All about comet Bernardinelli-Bernstein

Bernardinelli-Bernstein will not approach within a billion kilometers of Earth, according to the article. The object was discovered as part of the search for outer solar system objects with the Dark Energy Survey, according to the study. The announcement of the object was made on June 19, 2021.

Bernardinelli-Bernstein is the prominent archetype of distant comets, whose activity is driven by hypervolatiles (compounds such as carbon monoxide and methane), according to the study.

ALSO READ: WATCH | Asteroids, comets, meteors: what’s the difference? Listen to the NASA scientist

It is by far the largest Oort cloud object ever found and is almost twice as large as comet Hale-Bopp, according to the study. Oort Cloud is a predicted collection of icy objects that are more distant than all the rest of the solar system, and lie well beyond Pluto and the outermost edges of the Kuiper Belt, according to NASA. The Oort Cloud is believed to be the origin of many comets.

Comet Hale Bopp was an exceptionally bright comet that flew close to Earth in 1997 and was one of the brightest comets to reach the inner solar system in recorded history, according to NASA.

Dubbed the Great Comet of 1997, Hale Bopp was a record-breaking comet, with the largest well-measured cometary nucleus known after comet 95P/Chiron. Appearing 1,000 times brighter than Halley’s Comet from the same distance, Hale-Bopp was a very special comet because comets don’t typically shine as brightly when beyond Jupiter’s orbit, according to EarthSky .

As Bernardinelli-Bernstein will approach and pass perihelion, which is the closest point to the Sun in the path of an orbiting celestial body, monitoring dust and gas emissions will help study the pattern of comet activity and compare it to the distant Hale-Bopp activity, the authors noted in the study.

Quoting Samantha Lawler, a University of Regina astronomer who was not involved in the research, the indy100 article said the comet is huge and is by far the largest comet ever discovered.

When was the comet first spotted?

The comet was first spotted inadvertently by astronomers during a survey of galaxies in the deep cosmos in 2014, according to the article. Observations were made on August 8, 2021, at a distance of 20 astronomical units or nearly three billion kilometers from the Sun, according to the study.

The comet is heading for a perihelion of nearly 11 astronomical units, or 1.62 billion kilometers, in 2031, according to the study. This is the distance between Earth and Saturn.

The comet’s “heat flux” gives the surface diameter equivalent to the comet’s surface, according to the study. Then the albedo, which is the proportion of light reflected from the surface of an astronomical object, is determined from the usual relationship between diameter and magnitude H, which is the visual magnitude an observer would register if the he asteroid was placed at an astronomical position. unit away from the Sun and at zero phase angle.

Meanwhile, a recent study by researchers at the University of Cincinnati, USA, suggests that a near-Earth comet may have caused the rapid decline of the Hopewell culture, an ancient pre-Columbian Native American civilization. Falling debris from the comet created a devastating explosion over North America 1,500 years ago.

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The mega-comet passing through our solar system is 85, yes 85, miles wide https://sinia-planeta.com/the-mega-comet-passing-through-our-solar-system-is-85-yes-85-miles-wide/ Sat, 12 Feb 2022 12:00:00 +0000 https://sinia-planeta.com/the-mega-comet-passing-through-our-solar-system-is-85-yes-85-miles-wide/ There are genuine behemoths that sail around the solar system. In 2021, astronomers identified a gargantuan comet – an ancient mass of ice, dust and rock – passing through our cosmic neighborhood. Luckily, it won’t come within a billion miles of Earth. Named Comet Bernardinelli-Bernstein, it was possibly the largest comet ever detected, probably about […]]]>

There are genuine behemoths that sail around the solar system.

In 2021, astronomers identified a gargantuan comet – an ancient mass of ice, dust and rock – passing through our cosmic neighborhood. Luckily, it won’t come within a billion miles of Earth. Named Comet Bernardinelli-Bernstein, it was possibly the largest comet ever detected, probably about 10 times larger than the 6 mile wide object that hit Earth and triggered the extinction of the dinosaurs.

Now, new research more accurately assesses the size of the comet. It’s even bigger than some astronomers thought. In the new studyto be published in the scientific journal Astronomy & Astrophysicsscientists believe it is 85 miles wide.

If it stood next to Mount Everest, it would be about 15 times larger.

“It’s huge,” marveled Samantha Lawler, a University of Regina astronomer who studies objects deep in our solar system. “It is by far the largest comet ever discovered.” (Lawler had no role in the new research.)

“It’s enormous.”

There are almost certainly other deeply giant comets. We just have to keep looking. After all, Comet Bernardinelli-Bernstein, Lawler noted, was barely discovered. He was unknowingly picked up during a study of galaxies in the deep cosmos in 2014. Then he took years and using intensive computation for scientists to sift through numerous sightings and ultimately identify this distant monster (from June 2021, it was 1.8 billion miles from the sun).

“These big things are out there,” she said.

Like many other comets, Bernardinelli-Bernstein originated from the Oort cloud, a sphere of ancient and icy objects surrounding the solar system. There, disturbances, like another massive object passing by, can send a large ball of ice through our solar system. Comet Hale-Bopp, another visitor to the Oort Cloud, captivated skywatchers in 1996 and 1997.

Importantly, Hale-Bopp passed 122 million miles from Earth, which is relatively close in cosmic terms. Bernardinelli-Bernstein, more than twice the size of Hale-Bopp, will not approach Saturn’s orbit, about a billion kilometers away, in 2031.

Comet ISON photographed in 2013, some 80 million kilometers from Earth.
Credit: NASA/MSFC/Aaron Kingery

How can astronomers measure the size of such a distant object?

Simply looking at its luminosity (i.e. the amount of reflected sunlight) won’t be enough, explained Emmanuel Lellouch, an astronomer at the Paris Observatory and one of the study’s authors. From Earth, a large, dim object could have the same luminosity as a small but bright comet.

The astronomers have therefore measured the “thermal flux” of the comet, that is to say the amount of heat given off by the object. To do this, they look at a type of light called “infrared”. It is not visible to the human eye, but we feel this light when the sun shines on our skin. A larger object will absorb more sunlight and then radiate that energy. This information, combined with the object’s distance, gave Lellouch and his team a quality estimate of the comet’s size.

“It was in a freezer for billions of years.”

“It’s a way of finding out the size of something in the outer solar system without sending a probe there,” Lawler said.

In the years to come, the giant Bernardinelli-Bernstein will reveal bounties about our solar system. Scientists don’t think the comet ever traveled close to the sun, meaning the sun’s heat didn’t evaporate from its surface and form an iconic tail of dust and gas (called a coma). Instead, the comet has existed for eons on the outskirts of our solar system. It is a scientifically prized frozen artifact from the beginnings of our cosmic home. It’s a glimpse of what happened here about 4 billion years ago, just as the Earth was beginning to form.

“It was in a freezer for billions of years,” Lawler said.

SEE ALSO:

If a Scary Asteroid Actually Hits Earth, Here’s How You’ll Know

As the comet approaches the sun over the next decade, Lellouch noted that astronomers will observe dust and gases on this giant, ancient, and preserved piece of ice and rock.

“It’s never come this close to the sun,” Lawler said.

Related video: Mars will kill you in ways you never imagined

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137 km wide megacomet officially the largest ever seen https://sinia-planeta.com/137-km-wide-megacomet-officially-the-largest-ever-seen/ Tue, 08 Feb 2022 03:29:13 +0000 https://sinia-planeta.com/137-km-wide-megacomet-officially-the-largest-ever-seen/ For scientists, it’s called Comet 2014 UN271/(Bernardinelli-Bernstein). But to ordinary people, it’s a gargantuan megacomet that spans a jaw-dropping 137 kilometers wide, officially making it the largest comet ever measured. Think of a straight from Sydney to Newcastle, and that’s about the staggering width of Bernardinelli-Bernstein. Artist’s impression of what distant comet Bernardinelli-Bernstein might look […]]]>

For scientists, it’s called Comet 2014 UN271/(Bernardinelli-Bernstein).

But to ordinary people, it’s a gargantuan megacomet that spans a jaw-dropping 137 kilometers wide, officially making it the largest comet ever measured.

Think of a straight from Sydney to Newcastle, and that’s about the staggering width of Bernardinelli-Bernstein.

Artist’s impression of what distant comet Bernardinelli-Bernstein might look like in the outer solar system. (NOIRLab/NSF/AURA/J. da Silva (Space Engine))

The first images of Bernardinelli-Bernstein were recorded in 2014, when it was spotted 4.59 billion kilometers from Earth, roughly the same distance as the planet Neptune.

Initially, the comet was estimated to be between 100 and 370 kilometers wide.

Now these measures have been strengthened.

“We have confirmed the estimate,” said Dr Emmanuel Lellouch of the Paris Observatory. new scientist.

“It is the largest Oort cloud comet ever discovered.”

The news means Bernardinelli-Bernstein knocked Hale-Bopp, around 70 kilometers wide, from first place.

'Tree trunk' ;  broken crater on Mars.  Patterns inside this ice-rich crater reveal details about Mars' history

The “Tree trunk” crater broke on Mars

During its formation, massive pieces of rock and ice were catapulted into the Oort cloud by the newly formed solar system along with space junk from other planetary systems.

Researchers believe it holds clues to our sun’s long-lost twin and is part of the binary system theory.

Scientists believe the Oort Cloud may have played an important role in Earth’s history, including causing the extinction of the dinosaurs.

It also contains clues to the mysterious Planet Nine which astronomers have yet to prove exists.

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Comparison of objects in our solar system by rotation, size, etc. https://sinia-planeta.com/comparison-of-objects-in-our-solar-system-by-rotation-size-etc/ Sat, 05 Feb 2022 00:37:03 +0000 https://sinia-planeta.com/comparison-of-objects-in-our-solar-system-by-rotation-size-etc/ Pluto and the introduction of dwarf planets Since its discovery in 1930, Pluto has been a bit of a puzzle. For starters, not only is Pluto smaller than any other planet in the solar system, it’s also smaller than Earth’s moon. It also has an extremely weak gravitational pull at only 0.07 times the mass […]]]>

Pluto and the introduction of dwarf planets

Since its discovery in 1930, Pluto has been a bit of a puzzle.

For starters, not only is Pluto smaller than any other planet in the solar system, it’s also smaller than Earth’s moon. It also has an extremely weak gravitational pull at only 0.07 times the mass of objects in its orbit, which is only a fraction of the strength of the Moon.

At the same time, the surface of Pluto resembles that of terrestrial planets such as Mars, Venus or Earth, but its closest neighbors are the gaseous planets Jovian planets like Uranus or Neptune. In fact, Pluto’s orbit is so erratic that it led many scientists to initially believe that it originated elsewhere in space and that the Sun’s gravity pulled it in.

These qualities have challenged the scientific view of Pluto’s status as a planet for years. It was not until the discovery of Eris in 2005, one of many increasingly identified trans-Neptunian objects (objects beyond the planet Neptune), that the International Astronomical Union (IAU) defined criteria for classifying planets.

With Eris and other trans-Neptunian objects sharing similar characteristics with Pluto, the definition of dwarf planets was created and Pluto was downgraded in 2006.

So what are dwarf planets, how do they differ from “real” planets and what are their characteristics?

The history of dwarf planets

A dwarf planet is a celestial body that almost meets the definition of a “real” planet. According to the IAU, which establishes definitions for planetary science, a planet must:

  1. In orbit around the Sun.
  2. Have enough mass to achieve hydrostatic equilibrium and assume an almost round shape.
  3. Dominate its orbit and do not share it with other objects.

Dwarf planets, in addition to not being moons or satellites, fail to clear the quarters around their orbits. This is the main reason Pluto lost its status: because it shares part of its orbit with the Kuiper Belt, a dense region of icy space bodies.

Based on this definition, the IAU recognized five dwarf planets: Pluto, Eris, Makemake, Haumea and Ceres. There are four other planetary objects*, namely Orcus, Sedna, Gonggong and Quaoar, which the majority of the scientific community recognizes as dwarf planets.

Six more could be recognized in the years to come, and up to 200 or more are believed to exist in the outer solar system in the Kuiper Belt.

Ceres is the oldest known and the smallest of the current category of dwarf planets. Previously classified as an asteroid in 1801, it was confirmed to be a dwarf planet in 2006. Ceres lies between Mars and Jupiter in the asteroid belt, and is the only dwarf planet that orbits the closer to Earth.

Here is a brief introduction to the most recognized dwarf planets:

Last name Region of
Solar system
Orbital period
(in years)
Mean Orbital
speed (km/s)
Diameter
(km)
Diameter
related to
the moon
Moons
orcus Kuiper belt (plutin) 247 4.75 910 26% 1
Ceres asteroid belt 4.6 17.9 940 27% 0
Pluto Kuiper belt (plutin) 248 4.74 2377 68% 5
haumea Kuiper Belt (12:7) 285 4.53 1560 ≈ 45% 2
Quaoar Kuiper belt (cubewano) 289 4.51 1110 32% 1
makemake Kuiper belt (cubewano) 306 4.41 1430 41% 1
gong gong Scattered disc (10:3) 554 3.63 1230 35% 1
Eris Scattered Disc 558 3.62 2326 67% 1
Sedna Detached ~11,400 ~1.3 995 29% N / A

Interesting facts about dwarf planets

Here are some interesting facts about the dwarf planets discovered in our solar system:

Ceres loses 6 kg of its mass in vapor every second

The Herschel Space Telescope observed plumes of water vapour springing from the surface of Ceres; it was the first definitive observation of water vapor in the asteroid belt. This happens when parts of Ceres’ icy surface heat up and turn into vapor.

A day on Haumea lasts 3.9 hours

Haumea has a unique appearance due to its rotation, which is so fast that it compresses the planet into an egg-like shape. Its rotational speed and collisional origin also make Haumea one of the densest dwarf planets discovered to date.

Makemake was named three years after its discovery in 2005

The discovery of Makemake near Easter influenced both its name and nickname. Before being named after the creator of humanity and god of fertility in the myth of the Rapa Nui (native people of Easter Island), Makemake was nicknamed “Easter Bunny” by its discoverer Mike Brown.

Eris was once considered for the position of the 10th planet

Eris is the most massive dwarf planet in the solar system, surpassing the mass of Pluto by 28%. As such, it was a strong contender to become the tenth planet but failed to meet the criteria set by the IAU.

Pluto is one-third ice

The planet’s composition is two-thirds rock and one-third ice, mostly a mixture of methane and carbon dioxide. One day on Pluto is 153.6 hoursabout 6.4 Earth daysmaking it one of the slowest-rotating dwarf planets.

Exploratory missions and new planets on the horizon

With newer technology rapidly available to the scientific community and new exploratory missions obtaining more data and information on trans-Neptunian objects, our understanding of dwarf planets will increase.

Nestled in the asteroid belt between Mars and Jupiter, the asteroid Hygiea remains controversial. Hygiea is the fourth largest object in the asteroid belt behind Ceres, Vesta and Pallas and ticks all the boxes necessary to be classified as a dwarf planet.

So what’s holding back Hygiea’s confirmation as a dwarf planet? The criterion of being massive enough to form a spherical shape is in contention; it is unclear if its roundness is a result of collision/impact disturbance or its mass/gravity.

Along with Hygiea, other exciting dwarf planets may soon be discovered. Here is a brief overview of some serious contenders:

120347 Salacia

Discovered in 2004, it is a trans-Neptunian object in the Kuiper belt, approximately 850 kilometers in diameter. In 2018, it is located approximately 44.8 astronomical units of the sun. Salacia’s status is in contention because her planetary density is questionable. It is not certain that it can exist in hydrostatic equilibrium.

(307261) 2002MS4

With an estimated diameter of 934±47 kilometers, 2002 MS4 is comparable in size to Ceres. Researchers need more data to determine whether 2002 MS4 is a dwarf planet or not.

(55565) 2002AW197

Discovered at the Palomar Observatory in 2002, it has a rotation period of 8.8 hours, a moderately red color (similar to Quaoar) and no apparent planetary geology. It’s low albedo has made it difficult to determine whether or not it is a dwarf planet.

174567 Varda

Varda is named after the Queen of the Valar, creator of the stars, one of the most powerful servants of the almighty Eru Iluvatar in JRR Tolkien’s fictional mythology. Varda’s status as a dwarf planet is uncertain as its size and albedo suggest it may not be an entirely solid body.

(532037) Financial year 201327

This space object has a surface diameter of approximately 740 kilometers. It orbits the Sun once a 449 years. Researchers need more data on the mass and density of the planet to determine whether or not it is a dwarf planet.

(208996) 2003AZ84

It’s about 940 kilometers on its longest axis, because it has an elongated shape. This shape is likely due to its rapid rotation rate of 6.71 hours, similar to that of other dwarf planets like Haumea. Like Varda, it is still unclear whether this object compressed into an entirely solid body and therefore remains controversial among astronomers regarding its planetary status.

*Note: The IAU officially recognizes five dwarf planets. We include four additional dwarf planets widely recognized by members of the scientific community, especially among leading planetary researchers like Gonzalo Tancredi, Michael Brown, and William Grundy. There are many other potential dwarf planets not listed here that remain under investigation.

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Bad astronomy | TOI-2257b is a rare exoplanet, a giant orbiting a dwarf star https://sinia-planeta.com/bad-astronomy-toi-2257b-is-a-rare-exoplanet-a-giant-orbiting-a-dwarf-star/ Fri, 21 Jan 2022 14:00:13 +0000 https://sinia-planeta.com/bad-astronomy-toi-2257b-is-a-rare-exoplanet-a-giant-orbiting-a-dwarf-star/ One of my favorite things about the large number of exoplanets detected so far – coming out of 5,000 of these extraterrestrial worlds – is that with so many discoveries, you can see trends in their characteristics, as well as find eccentrics who fall far from trends. In our solar system, for example, the planets […]]]>

One of my favorite things about the large number of exoplanets detected so far – coming out of 5,000 of these extraterrestrial worlds – is that with so many discoveries, you can see trends in their characteristics, as well as find eccentrics who fall far from trends.

In our solar system, for example, the planets are well spaced and have fairly circular orbits. But it’s not always the case.

TOI-2257 is a red dwarf, a small, dim, low-mass star about 188 light-years from Earth. It is about 1/3 the mass and diameter of the Sun, appears to be about 8 billion years old – much older than the Sun – and is so faint at this distance that it merges with the millions and millions of stars surrounding it.

Except in 2019, the Transiting Exoplanet Survey Satellite, or TESS, noticed the star dimming for a short time, then brightening again. This behavior was also repeated 175 days later. It only fell by about 0.4%, but that has the signature of a transit, when a planet orbiting the star blocks its light as seen from Earth during a mini-eclipse.

An alert was sent to planetary astronomers, and a team jumped on it. If the planet has a 176-day orbit, it would be six months before they could see another transit, but TESS hasn’t observed it continuously, so it’s possible it had a shorter orbit with a simple fraction of this period, such as a half or a third.

Follow-up observations ruled out the 57-day orbit – a third of 176 – but more observed transits established the planet to have a 35.2-day orbit, a fifth of 176 – so its year is a bit longer of an earth month.

Once confirmed, the planet was given the designation TOI-2257b.

The amount of light from the star that is blocked depends on the size of the star and the planet. To make the light of this small star fall by 0.4%, you need a planet about 2.2 times the diameter of Earth. From what we know of planet formation, it’s a little too big to be a rocky planet like Earth, because planets that size are big enough to start sucking a lot of gas around them at as they form, becoming more like mini-Neptunes: a rocky core surrounded by a thick atmosphere. Models indicate that the most likely mass of TOI-2257b is 5.6 times that of Earth, although this is highly uncertain. Neptune, for comparison, is just under 4 times the diameter of Earth and 17 times its mass.

It’s already interesting. Red dwarfs are low-mass stars, and given what we’ve seen of their systems, they don’t usually have giant planets orbiting them. They’re really good at creating Earth-sized planets – TRAPPIST-1, a nearby star bulb, has Seven small planets orbiting around it. Additionally, these planets tend to be very close to the star – TRAPPIST-1’s planets could all fit inside Mercury’s orbit around the Sun. A 35-day orbit is unusual, and for a red dwarf planet, TOI-2257b is technically a long period.

Where it gets interesting is when they looked at the orbit itself (link to paper). Modeling transit behavior can provide insight into the shape of the orbit; for example, if you assume a circular orbit, the transit should take some time, but if the orbit is elliptical, the planet is moving at different speeds at different times, which changes the duration of the transit.

What they found was that the best fit to the orbit gives them a suitably elongated ellipse with an eccentricity of about 0.5. It’s also unusual! The most likely reason is a second giant planet orbiting even further away. Over time, this planet’s gravity can pull on TOI-2257b’s orbit, making it more elongated.

This gravitational tug can also alter the timing between transits – this method of finding more invisible planets is called transit time variations. None were seen. It turns out that in systems where a large outer planet pulls on an inner planet, you usually only see one inner planet. This is probably due to the fact that this outer planet disturbs the other planets so much that they are ejected from the system. No other planets are seen orbiting TOI-2257, so this may imply the existence of another large planet in the system.

I’m giving a public talk titled “Strange New Worlds: Is Earth Special?” where I talk about exoplanets and how the Earth and the solar system compare to them. This TOI-2257 system is so different from ours! There can only be two worlds, both large, around a small star. TOI-2257b’s orbit is also more elliptical than any major planet in our system. It really shows how wildly different these planetary systems can be.

…except for one thing. At its distance from its star, TOI-2257b’s temperature is likely to be around the right value to support liquid water. Now the planet is a gas giant, so it doesn’t really have a surface, but it will have clouds and could hold a lot of water vapor. And if it has a big moon, it could be a miniature water world; many moons in the outer solar system are charged with water ice. Given models of such a system, TOI-2257b is unlikely to have a moon – the odds are about 1 in 7, given that it is close enough to its star that a gravitational disturbance could cause the ejection of its moon. But it’s not impossible, and looking for one would be interesting.

We know that life on Earth needs water, and water is an excellent medium for the genesis and support of living matter. There may be others, but we know water and we know how to find it. TOI-2257b is close enough and its star bright enough that future observations, like JWST’s, can show us if there is oxygen or water in its atmosphere. It’s not conclusive in terms of life, but it would be interesting.

With nearly 5,000 exoplanets discovered, we are bound to find oddballs. But when these oddballs share characteristics with Earth, I find it encouraging. It’s an imperfect match at best, but it shows us that the Universe is capable of great diversity, and that in itself shows us that we need to broaden our view of it.

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Stardust: The mission that forever changed our understanding of comets https://sinia-planeta.com/stardust-the-mission-that-forever-changed-our-understanding-of-comets/ Sat, 15 Jan 2022 15:29:27 +0000 https://sinia-planeta.com/stardust-the-mission-that-forever-changed-our-understanding-of-comets/ AD: Can you tell us about your experience recovering the sample collector? Brownlee: It was the middle of the night in a very remote place in Utah [the capsule was recovered in Dugway, Utah, in the west desert near the Great Salt Lake]. The entrance to the capsule was a wonder. It was [a] glowing […]]]>

AD: Can you tell us about your experience recovering the sample collector?

Brownlee: It was the middle of the night in a very remote place in Utah [the capsule was recovered in Dugway, Utah, in the west desert near the Great Salt Lake]. The entrance to the capsule was a wonder. It was [a] glowing fireball with a luminous tail coming from the west. It was descending and getting closer, but seen from Ground Zero, it was oddly rising in the sky. People nearby [the town of] Wendover heard the sonic boom and a NASA plane got spectacular footage, as did a Japanese film crew on the ground. I was outside to see the fireball, then inside to watch the images from the tracking devices. He landed in the dark and it took several hours to find him. He was found by our helicopter crew and returned to a special clean room prepared for him where he was inspected and prepared for [a] flight the next day to Johnson Space Center in Houston.

AD: What did the analysis of comet dust particles tell us? What were the main conclusions?

Brownlee: The main finding is that the rocky components of the comet, most of its total mass, formed at scorching temperatures. The formation of comets included fire and ice. Some of the ice formed at temperatures near absolute zero, but the rocky material formed under white heat conditions. Many materials from the comet have also been found in meteorites. Comet Wild 2 is a broader mix of components suggesting that material from a wide range of locations was transported past Pluto where the comet formed. The rock materials primarily formed at temperatures above 1832 degrees Fahrenheit (1000 degrees Celsius) and could not have ice or organic material on them at the time of their formation. The comet’s rock silicate materials first formed, then came together with ice and organics in a considerably colder location. This proved that the formation of cometary dust and ice was clearly decoupled. The samples proved that the outer solar system was not isolated from the inner solar system and that materials clearly mixed in regions near the Sun to regions beyond Pluto’s orbit.

AD: Looking back on the mission all these years later, what are your fondest memories of the experience?

Brownlee: Launch: A totally amazing experience when it comes to your own mission. I watched the launch from a mile away, it was so clear we could see the 4 solid rocket motors separate and fall with the naked eye.

The overview: The tension was just incredible. As careful as you are, space exploration involves risks and unknowns, you are involved in a strange game of Russian roulette. Throughout the mission, [I] felt like a soldier on the beach on d-day [in World War II]. Bullets whiz around you and you hope they don’t hit you.

Atmospheric Entry and Recovery: The launch was so impressive that many had tears in their eyes. It had nothing to do with the fireball entering the Sample Return Pod in the middle of the night, in the middle of the desert with a glowing glowing tail behind it.

Opening the collector: We opened the collector in a special clean room at the Johnson Space Center. Mike Zolensky and I were the only ones close by and when the airgel array was finally exposed we were watching it from the back. We couldn’t see the impacts and the airgel looked even better than before launch. We wondered if the collector had actually opened. We were nervous, but we felt like we were seeing capture trails, but [were] not sure because we were looking through the back of about 1.6 inches (4 centimeters) of airgel. When the collector was raised, we could instantly see the catch tracks clearly.

Probably my biggest thrill of the mission was presenting the first results of the sample analysis at the annual Lunar and Planetary Science Conference, just 3 months after landing. When I showed the results to 600 people crammed into the room, you could hear gasps and see jaws drop. We had gone to see a type of body famous for its ice, a body whose dust was believed to be dominated by solids formed around other stars. We had discovered that it contained the hottest material that could have existed in the solar system. Finding such material in a comet was revolutionary. Our modest mission had sent samples back to Earth that taught us things about comets that we could never. [have] known by remote sensing methods.


Doug Adler is the co-host of The good companion podcast and book co-author: From the Earth to the Moon: The Companion to the Miniseries

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The first rings of the sun prevented our planet from becoming a “super-Earth” https://sinia-planeta.com/the-first-rings-of-the-sun-prevented-our-planet-from-becoming-a-super-earth/ Thu, 13 Jan 2022 12:57:35 +0000 https://sinia-planeta.com/the-first-rings-of-the-sun-prevented-our-planet-from-becoming-a-super-earth/ The sun was once surrounded by rings of gas and dust similar to those orbiting Saturn, a new study published in the journal natural astronomy reveals. These rings played a vital role in the formation of our solar system and in the size and habitability of the Earth. Rings of dust and gas from the […]]]>

The sun was once surrounded by rings of gas and dust similar to those orbiting Saturn, a new study published in the journal natural astronomy reveals.

These rings played a vital role in the formation of our solar system and in the size and habitability of the Earth.

Rings of dust and gas from the early sun may have prevented our planet from becoming a “super-Earth”, according to the Rice University astrophysicists behind the new paper. “In the solar system, something happened to prevent Earth from expanding into a much larger type of terrestrial planet called super-Earth,” Rice University astrophysicist André Izidoro said in A press release.

Super-Earths are huge, rocky planets that have been observed around about 30% of the sun-like stars in the Milky Way. Using advanced computer modeling to simulate the formation of our solar system, Rice University scientists observed that the early sun likely produced three bands of high pressure, called “pressure humps”, which were observed around distant stars. These discs likely prevented the necessary material from reaching Earth, making it a “super-Earth”, the scientists explained.

Why we don’t have a super-Earth in our solar system

“If super-Earths are super-common, why don’t we have one in the solar system?” said Izidoro. “We propose that pressure bumps produce disconnected reservoirs of disk material in the inner and outer solar system and regulate the amount of material available to grow planets in the inner solar system.”

In their simulations, Izidro said the timing of the formation of pressure bumps was found to be crucial in the formation of super-Earths. “At the time the pressure hump formed in [some] case, a lot of mass had already invaded the inner system and was available to create super-Earths,” he said. “So the timing of when this medium pressure hump formed could be a key aspect of the solar system.”

The researchers’ modeling provides new insights into the very early formation of our solar system, and the model accurately reproduces known features of our solar system that were missed by other previous models, the researchers said. Soon, new data from the recently launched James Webb Space Telescope will provide deeper insight into the early composition of solar systems and allow the scientific community to compare these models to distant approximations of reality.

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Saturn-Like Rings Around the Sun Prevented Our Planet From Becoming a ‘Super-Earth’, New Study Says https://sinia-planeta.com/saturn-like-rings-around-the-sun-prevented-our-planet-from-becoming-a-super-earth-new-study-says/ Wed, 12 Jan 2022 08:00:00 +0000 https://sinia-planeta.com/saturn-like-rings-around-the-sun-prevented-our-planet-from-becoming-a-super-earth-new-study-says/ The Sun had rings of dust and gas similar to Saturn that may have played a vital role in the formation of the Earth, according to a new study. “In the solar system, something happened to prevent Earth from expanding into a much larger type of terrestrial planet called a super-Earth,” said Rice University astrophysicist […]]]>

The Sun had rings of dust and gas similar to Saturn that may have played a vital role in the formation of the Earth, according to a new study.

“In the solar system, something happened to prevent Earth from expanding into a much larger type of terrestrial planet called a super-Earth,” said Rice University astrophysicist Andre Izidoro.

Super-Earths are massive, rocky planets seen around at least 30% of the Sun-like stars in the galaxy.

Using a supercomputer to simulate the formation of the solar system, the model produced rings around the Sun like those seen around young stars.

The model assumes that three bands of high pressure appeared in the young Sun’s disk of gas and dust – called “pressure humps” – which have also been observed in ringed stellar disks around distant stars.

“If super-Earths are super-common, why don’t we have one in the solar system?” said Izidoro. “We propose that pressure bumps produce disconnected reservoirs of disk material in the inner and outer solar system and regulate the amount of material available to grow planets in the inner solar system.”

Scientists have thought for decades that the gas and dust in disks become progressively less dense, but computer simulations tell a different story: planets are unlikely to form in smooth disk scenarios.

“In a smooth disk, any solid particles – grains of dust or rocks – should be drawn inwards very quickly and lost within the star,” said astronomer and study co-author Andrea Isella, associate professor of physics and astronomy at Rice. “It takes something to stop them to give them time to become planets.”

When the particles move faster than the gas around them, they “sense a headwind and drift very quickly toward the star,” Izidoro said.

The study’s model assumed that pressure bumps formed in the early solar system at three locations.

“It’s just a function of the distance from the star, because the temperature increases as you get closer to the star,” said geochemist and study co-author Rajdeep Dasgupta, Professor Maurice Ewing of Earth systems science at Rice. “The point where the temperature is high enough for ice to vaporize, for example, is a line of sublimation which we call the snow line.”

At the silicate line, the basic ingredient of sand and glass, silicon dioxide, has become steam. This produced the ring closest to the Sun, where Mercury, Venus, Earth and Mars would later form.

The middle ring appeared at the snow line and the farthest ring at the carbon monoxide line.

Izidoro said the delayed appearance of the sun’s central ring in some simulations has led to the formation of super-Earths, which underscores the importance of timing pressure bumps.

“By the time the pressure hump formed in these cases, a lot of mass had already invaded the internal system and was available to create super-Earths,” he said. “So the timing of when this mid-pressure hump formed could be a key aspect of the solar system.”

The study was published online in natural astronomy,

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Why 2029 is crucial for studying the solar system’s most controversial orb https://sinia-planeta.com/why-2029-is-crucial-for-studying-the-solar-systems-most-controversial-orb/ Sat, 08 Jan 2022 21:00:25 +0000 https://sinia-planeta.com/why-2029-is-crucial-for-studying-the-solar-systems-most-controversial-orb/ [ad_1] Object 90377 Sedna – a distant transneptunian object best known for its 11,390-year highly elliptical orbit – is currently en route to perihelion (its closest approach to the Sun) in 2076. After that, Sedna will set off again in deep space and not return for millennia, making this flyby a unique opportunity (or, once […]]]>


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Object 90377 Sedna – a distant transneptunian object best known for its 11,390-year highly elliptical orbit – is currently en route to perihelion (its closest approach to the Sun) in 2076.

After that, Sedna will set off again in deep space and not return for millennia, making this flyby a unique opportunity (or, once in ~ 113 lifetimes) to study an object from the far reaches of our solar system.

There are no missions to Sedna in preparation yet, but astronomers are starting to anticipate this possibility. The ideal launch date for such a mission is fast approaching, with two of the best launch windows coming in 2029 and 2034.

Sedna was discovered in 2003 by Caltech astronomer Mike Brown and his team and was one of a series of potential dwarf planets (alongside similarly sized bodies like Haumea, Makemake, and Eris) whose discovery led to the demotion of Pluto in 2006.

As far as we can tell from a distance, Sedna is roughly the same size as Ceres, the largest object in the asteroid belt, but its makeup and origins are very different. Its chemical makeup suggests that it could be coated with deep reddish organic compounds called tholins, the same material seen on Pluto and other objects in the Kuiper Belt.

Unlike Pluto, it is usually too cold for the methane abundant on its surface to evaporate and fall back as snow, although Sedna may briefly gain an atmosphere of nitrogen as the Sun approaches.

What sets Sedna apart from other known candidate dwarf planets is its enormous orbit, which brings it to the inner edge of the Oort Cloud, the furthest region in the solar system, where long-lived comets lurk. There are several competing theories as to how Sedna got into this position.

Perhaps the most publicized theory is the possibility that an as yet unknown ninth planet, perhaps 10 times the size of Earth, disrupted Sedna’s orbit and dragged her, along with several other objects, onto very elongated eye sockets. Visiting Sedna probably won’t solve this particular mystery, but it will tell us a lot about the makeup of these extreme Transneptunian objects.

The orbit of candidate dwarf planet 90377 Sedna (red) relative to Jupiter (orange), Saturn (yellow), Uranus (green), Neptune (blue) and Pluto (purple).Wikimedia Commons

Reaching Sedna with a spaceship will not be an easy task. Even at its closest approach, Sedna will only come to about 76 AU from the Sun. By way of comparison, Neptune measures about 30 AU, and the Voyager missions, launched in 1977, have just crossed 150 AU and 125 AU respectively. This means that the time to throw is sooner rather than later.

When planning a mission to Sedna, Voyager spacecraft are not a bad place to look for inspiration. They took advantage of a lucky alignment of planets to take a grand tour of the outer solar system, stealing energy from Jupiter to gain speed and hit their more distant targets.

Similar gravity aids will be needed to make the trip to Sedna manageable. A team of scientists led by Vladislav Zubko of the Russian Academy of Sciences’ Institute for Space Research recently modeled a series of possible trajectories to Sedna, prioritizing a launch date of 2029 as the most feasible option.

The 2029 trajectory, they determined, would take the spacecraft to Venus first, then back to Earth (twice), before passing Jupiter on the way to Sedna, with flight times as short as 20 years. but most optimally in the 30 year range. The longer flight time would increase the spacecraft’s altitude above Jupiter during gravity assist, thereby reducing the time spent being exposed to harmful radiation from the gas giant.

A 30-year flight plan would also mean going through Sedna more slowly, giving more time to collect data on the object. Choosing this option would give the spacecraft a relative speed of 13.70 km / s (29,000 mph) during its passage through Sedna, comparable to the speed at which New Horizons approached Pluto in 2015.

90377 Sedna as seen by the Hubble Space Telescope in 2004.Nasa

As an added bonus, this trajectory would also take the spacecraft past a 145 km (90 mile) diameter asteroid named Massalia, giving the team an additional scientific target to study, as well as a chance to test the systems. of the spaceship.

A second trajectory proposed by the team would consist of a launch in 2034 and provide a similar additional flyby, this time over the metallic asteroid 16 Psyche.

At this time, it’s unclear whether a mission to Sedna will hit the launch pad with all of the competing options available to mission planners in the next decade or so. But since this is our only chance for the next 11,000 years, the idea will certainly be given careful consideration.

This article was originally published on Universe today by Scott Alan Johnston. Read it original article here.

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