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Other solar systems with earth like planets

shunyadragon

shunyadragon
Premium Member
The ability of astronomers and cosmologists to locate planets in other solar systems is increasing.

First Habitable-Zone, Earth-Sized Exoplanet Discovered With Planet-Hunter TESS

First Habitable-Zone, Earth-Sized Exoplanet Discovered With Planet-Hunter TESS
TOPICS:AstronomyAstrophysicsHarvard-Smithsonian Center For AstrophysicsPopularTESS

By HARVARD-SMITHSONIAN CENTER FOR ASTROPHYSICS OCTOBER 25, 2020


TOI 700, a planetary system 100 light-years away in the constellation Dorado, is home to TOI 700 d, the first Earth-size habitable-zone planet discovered by NASA’s Transiting Exoplanet Survey Satellite. Credit: NASA’s Goddard Space Flight Center

TESS, the Transiting Exoplanet Survey Satellite, was launched in 2018 with the goal of discovering small planets around the Sun’s nearest neighbors, stars bright enough to allow for follow-up characterizations of their planets’ masses and atmospheres. TESS has so far discovered seventeen small planets around eleven nearby stars that are M dwarfs — stars that are smaller than the Sun (less than about 60% of the Sun’s mass) and cooler (surface temperatures less than about 3900 kelvin). In a series of three papers that appeared together this month, astronomers report that one of these planets, TOI-700d, is Earth-sized and also located in its star’s habitable zone; they also discuss its possible climate.

CfA astronomers Joseph Rodriguez, Laura Kreidberg, Karen Collins, Samuel Quinn, Dave Latham, Ryan Cloutier, Jennifer Winters, Jason Eastman, and David Charbonneau were on the teams that studied TOI-700d, one of three small planets orbiting one M dwarf star (its mass is 0.415 solar masses) located one hundred and two light-years from Earth. The TESS data analysis found the tentative sizes of the planets as being approximately Earth-sized, 1.04, 2.65 and 1.14 Earth-radii, respectively, and their orbital periods as 9.98, 16.05, and 37.42 days, respectively.


This illustration of TOI 700 d is based on several simulated environments for an ocean-covered version of the planet. Credit: NASA’s Goddard Space Flight Center

In our solar system, Mercury orbits the Sun in about 88 days; it is so close to the Sun that its temperature can reach over 400 Celsius. But because this M-dwarf star is comparatively cool the orbit of its third planet, even though much closer to the star than Mercury is to the Sun, places it in the habitable zone – the region within which the temperatures allow surface water (if any) to remain liquid when there is also an atmosphere. That makes this Earth-sized planet TOI-700d particularly interesting as a potential host for life.

The TESS detections were exciting but uncertain: the signals were faint and a small possibility remained that the TOI-700d detection was spurious. Because of the potential importance of finding a nearby Earth-sized planet in a habitable zone, the TESS scientists turned to the IRAC camera on the Spitzer Space Observatory for confirmation. Before being turned off by NASA in February 2020, the IRAC camera was by far the most sensitive near infrared camera in space.



A schematic of the planets around the nearby M dwarf star TOI-700, discovered by TESS. The third (the farthest planet from the star), TOI-700d, lies within the star’s habitable zone (shown in green). Using the IRAC camera on Spitzer, the team refined the planet’s mass as 2.1 Earth-masses and 1.14 Earth-radii. (The scale shows 0.2 astronomical units; AU being the average Earth-Sun distance.) Credit: Rodriguez et al 2020

The TESS team observed TOI-700 with IRAC in October of 2019 and January of 2020, acquiring clear detections of the planets with about twice the signal-to-noise of TESS, enough to give a 61% improvement in the planet’s orbit and to significantly refine our knowledge of its other characteristics, refining the radius as above and finding the mass to be 2.1 Earth-masses. The results, especially when compared with other planets’ properties, suggest that this planet may be rocky and likely to be “tidally locked” with one side of the planet always facing the star.

If there were liquid water on the surface of TOI-700d, the astronomers argue, there would also be water-bearing clouds in the atmosphere, and the team uses climate system models to estimate its possible properties and what more sensitive measurements might find. They conclude, however, that pending space missions, including JWST, will probably lack the sensitivity to detect atmospheric features by a factor of ten or more. Their detailed climate studies will nevertheless help astronomers constrain the kinds of telescopes and instruments that will be needed to investigate this exciting new neighbor.


NASA’s Transiting Exoplanet Survey Satellite (TESS) has discovered its first Earth-size planet in its star’s habitable zone, the range of distances where conditions may be just right to allow the presence of liquid water on the surface. Scientists confirmed the find, called TOI 700 d, using NASA’s Spitzer Space Telescope and have modeled the planet’s potential environments to help inform future observations. Credit: NASA’s Goddard Space Flight Center

References:

“The First Habitable-zone Earth-sized Planet from TESS. I. Validation of the TOI-700 System” by Emily A. Gilbert, Thomas Barclay, Joshua E. Schlieder, Elisa V. Quintana, Benjamin J. Hord, Veselin B. Kostov, Eric D. Lopez, Jason F. Rowe, Kelsey Hoffman, Lucianne M. Walkowicz, Michele L. Silverstein, Joseph E. Rodriguez, Andrew Vanderburg, Gabrielle Suissa, Vladimir S. Airapetian, Matthew S. Clement, Sean N. Raymond, Andrew W. Mann, Ethan Kruse … Benjamin J. Shappee, Mackennae Le Wood and Jennifer G. Winters, 14 August 2020, The Astronomical Journal.
DOI: 10.3847/1538-3881/aba4b2
 

Brickjectivity

Turned to Stone. Now I stretch daily.
Staff member
Premium Member
The ability of astronomers and cosmologists to locate planets in other solar systems is increasing.

First Habitable-Zone, Earth-Sized Exoplanet Discovered With Planet-Hunter TESS

First Habitable-Zone, Earth-Sized Exoplanet Discovered With Planet-Hunter TESS
TOPICS:AstronomyAstrophysicsHarvard-Smithsonian Center For AstrophysicsPopularTESS

By HARVARD-SMITHSONIAN CENTER FOR ASTROPHYSICS OCTOBER 25, 2020


TOI 700, a planetary system 100 light-years away in the constellation Dorado, is home to TOI 700 d, the first Earth-size habitable-zone planet discovered by NASA’s Transiting Exoplanet Survey Satellite. Credit: NASA’s Goddard Space Flight Center

TESS, the Transiting Exoplanet Survey Satellite, was launched in 2018 with the goal of discovering small planets around the Sun’s nearest neighbors, stars bright enough to allow for follow-up characterizations of their planets’ masses and atmospheres. TESS has so far discovered seventeen small planets around eleven nearby stars that are M dwarfs — stars that are smaller than the Sun (less than about 60% of the Sun’s mass) and cooler (surface temperatures less than about 3900 kelvin). In a series of three papers that appeared together this month, astronomers report that one of these planets, TOI-700d, is Earth-sized and also located in its star’s habitable zone; they also discuss its possible climate.

CfA astronomers Joseph Rodriguez, Laura Kreidberg, Karen Collins, Samuel Quinn, Dave Latham, Ryan Cloutier, Jennifer Winters, Jason Eastman, and David Charbonneau were on the teams that studied TOI-700d, one of three small planets orbiting one M dwarf star (its mass is 0.415 solar masses) located one hundred and two light-years from Earth. The TESS data analysis found the tentative sizes of the planets as being approximately Earth-sized, 1.04, 2.65 and 1.14 Earth-radii, respectively, and their orbital periods as 9.98, 16.05, and 37.42 days, respectively.


This illustration of TOI 700 d is based on several simulated environments for an ocean-covered version of the planet. Credit: NASA’s Goddard Space Flight Center

In our solar system, Mercury orbits the Sun in about 88 days; it is so close to the Sun that its temperature can reach over 400 Celsius. But because this M-dwarf star is comparatively cool the orbit of its third planet, even though much closer to the star than Mercury is to the Sun, places it in the habitable zone – the region within which the temperatures allow surface water (if any) to remain liquid when there is also an atmosphere. That makes this Earth-sized planet TOI-700d particularly interesting as a potential host for life.

The TESS detections were exciting but uncertain: the signals were faint and a small possibility remained that the TOI-700d detection was spurious. Because of the potential importance of finding a nearby Earth-sized planet in a habitable zone, the TESS scientists turned to the IRAC camera on the Spitzer Space Observatory for confirmation. Before being turned off by NASA in February 2020, the IRAC camera was by far the most sensitive near infrared camera in space.



A schematic of the planets around the nearby M dwarf star TOI-700, discovered by TESS. The third (the farthest planet from the star), TOI-700d, lies within the star’s habitable zone (shown in green). Using the IRAC camera on Spitzer, the team refined the planet’s mass as 2.1 Earth-masses and 1.14 Earth-radii. (The scale shows 0.2 astronomical units; AU being the average Earth-Sun distance.) Credit: Rodriguez et al 2020

The TESS team observed TOI-700 with IRAC in October of 2019 and January of 2020, acquiring clear detections of the planets with about twice the signal-to-noise of TESS, enough to give a 61% improvement in the planet’s orbit and to significantly refine our knowledge of its other characteristics, refining the radius as above and finding the mass to be 2.1 Earth-masses. The results, especially when compared with other planets’ properties, suggest that this planet may be rocky and likely to be “tidally locked” with one side of the planet always facing the star.

If there were liquid water on the surface of TOI-700d, the astronomers argue, there would also be water-bearing clouds in the atmosphere, and the team uses climate system models to estimate its possible properties and what more sensitive measurements might find. They conclude, however, that pending space missions, including JWST, will probably lack the sensitivity to detect atmospheric features by a factor of ten or more. Their detailed climate studies will nevertheless help astronomers constrain the kinds of telescopes and instruments that will be needed to investigate this exciting new neighbor.


NASA’s Transiting Exoplanet Survey Satellite (TESS) has discovered its first Earth-size planet in its star’s habitable zone, the range of distances where conditions may be just right to allow the presence of liquid water on the surface. Scientists confirmed the find, called TOI 700 d, using NASA’s Spitzer Space Telescope and have modeled the planet’s potential environments to help inform future observations. Credit: NASA’s Goddard Space Flight Center

References:

“The First Habitable-zone Earth-sized Planet from TESS. I. Validation of the TOI-700 System” by Emily A. Gilbert, Thomas Barclay, Joshua E. Schlieder, Elisa V. Quintana, Benjamin J. Hord, Veselin B. Kostov, Eric D. Lopez, Jason F. Rowe, Kelsey Hoffman, Lucianne M. Walkowicz, Michele L. Silverstein, Joseph E. Rodriguez, Andrew Vanderburg, Gabrielle Suissa, Vladimir S. Airapetian, Matthew S. Clement, Sean N. Raymond, Andrew W. Mann, Ethan Kruse … Benjamin J. Shappee, Mackennae Le Wood and Jennifer G. Winters, 14 August 2020, The Astronomical Journal.
DOI: 10.3847/1538-3881/aba4b2
What's your opinion: is it likely we'd find some kind of life? Taking stock of everything all at once, all the theories and convos and opinions you have considered: More likely or less likely that at least one other planet would have life on it? :cowface:
 

Left Coast

This Is Water
Staff member
Premium Member
The ability of astronomers and cosmologists to locate planets in other solar systems is increasing.

First Habitable-Zone, Earth-Sized Exoplanet Discovered With Planet-Hunter TESS

First Habitable-Zone, Earth-Sized Exoplanet Discovered With Planet-Hunter TESS
TOPICS:AstronomyAstrophysicsHarvard-Smithsonian Center For AstrophysicsPopularTESS

By HARVARD-SMITHSONIAN CENTER FOR ASTROPHYSICS OCTOBER 25, 2020


TOI 700, a planetary system 100 light-years away in the constellation Dorado, is home to TOI 700 d, the first Earth-size habitable-zone planet discovered by NASA’s Transiting Exoplanet Survey Satellite. Credit: NASA’s Goddard Space Flight Center

TESS, the Transiting Exoplanet Survey Satellite, was launched in 2018 with the goal of discovering small planets around the Sun’s nearest neighbors, stars bright enough to allow for follow-up characterizations of their planets’ masses and atmospheres. TESS has so far discovered seventeen small planets around eleven nearby stars that are M dwarfs — stars that are smaller than the Sun (less than about 60% of the Sun’s mass) and cooler (surface temperatures less than about 3900 kelvin). In a series of three papers that appeared together this month, astronomers report that one of these planets, TOI-700d, is Earth-sized and also located in its star’s habitable zone; they also discuss its possible climate.

CfA astronomers Joseph Rodriguez, Laura Kreidberg, Karen Collins, Samuel Quinn, Dave Latham, Ryan Cloutier, Jennifer Winters, Jason Eastman, and David Charbonneau were on the teams that studied TOI-700d, one of three small planets orbiting one M dwarf star (its mass is 0.415 solar masses) located one hundred and two light-years from Earth. The TESS data analysis found the tentative sizes of the planets as being approximately Earth-sized, 1.04, 2.65 and 1.14 Earth-radii, respectively, and their orbital periods as 9.98, 16.05, and 37.42 days, respectively.


This illustration of TOI 700 d is based on several simulated environments for an ocean-covered version of the planet. Credit: NASA’s Goddard Space Flight Center

In our solar system, Mercury orbits the Sun in about 88 days; it is so close to the Sun that its temperature can reach over 400 Celsius. But because this M-dwarf star is comparatively cool the orbit of its third planet, even though much closer to the star than Mercury is to the Sun, places it in the habitable zone – the region within which the temperatures allow surface water (if any) to remain liquid when there is also an atmosphere. That makes this Earth-sized planet TOI-700d particularly interesting as a potential host for life.

The TESS detections were exciting but uncertain: the signals were faint and a small possibility remained that the TOI-700d detection was spurious. Because of the potential importance of finding a nearby Earth-sized planet in a habitable zone, the TESS scientists turned to the IRAC camera on the Spitzer Space Observatory for confirmation. Before being turned off by NASA in February 2020, the IRAC camera was by far the most sensitive near infrared camera in space.



A schematic of the planets around the nearby M dwarf star TOI-700, discovered by TESS. The third (the farthest planet from the star), TOI-700d, lies within the star’s habitable zone (shown in green). Using the IRAC camera on Spitzer, the team refined the planet’s mass as 2.1 Earth-masses and 1.14 Earth-radii. (The scale shows 0.2 astronomical units; AU being the average Earth-Sun distance.) Credit: Rodriguez et al 2020

The TESS team observed TOI-700 with IRAC in October of 2019 and January of 2020, acquiring clear detections of the planets with about twice the signal-to-noise of TESS, enough to give a 61% improvement in the planet’s orbit and to significantly refine our knowledge of its other characteristics, refining the radius as above and finding the mass to be 2.1 Earth-masses. The results, especially when compared with other planets’ properties, suggest that this planet may be rocky and likely to be “tidally locked” with one side of the planet always facing the star.

If there were liquid water on the surface of TOI-700d, the astronomers argue, there would also be water-bearing clouds in the atmosphere, and the team uses climate system models to estimate its possible properties and what more sensitive measurements might find. They conclude, however, that pending space missions, including JWST, will probably lack the sensitivity to detect atmospheric features by a factor of ten or more. Their detailed climate studies will nevertheless help astronomers constrain the kinds of telescopes and instruments that will be needed to investigate this exciting new neighbor.


NASA’s Transiting Exoplanet Survey Satellite (TESS) has discovered its first Earth-size planet in its star’s habitable zone, the range of distances where conditions may be just right to allow the presence of liquid water on the surface. Scientists confirmed the find, called TOI 700 d, using NASA’s Spitzer Space Telescope and have modeled the planet’s potential environments to help inform future observations. Credit: NASA’s Goddard Space Flight Center

References:

“The First Habitable-zone Earth-sized Planet from TESS. I. Validation of the TOI-700 System” by Emily A. Gilbert, Thomas Barclay, Joshua E. Schlieder, Elisa V. Quintana, Benjamin J. Hord, Veselin B. Kostov, Eric D. Lopez, Jason F. Rowe, Kelsey Hoffman, Lucianne M. Walkowicz, Michele L. Silverstein, Joseph E. Rodriguez, Andrew Vanderburg, Gabrielle Suissa, Vladimir S. Airapetian, Matthew S. Clement, Sean N. Raymond, Andrew W. Mann, Ethan Kruse … Benjamin J. Shappee, Mackennae Le Wood and Jennifer G. Winters, 14 August 2020, The Astronomical Journal.
DOI: 10.3847/1538-3881/aba4b2

Thanks for sharing! How far is this star/planet from Earth?
 

shunyadragon

shunyadragon
Premium Member
What's your opinion: is it likely we'd find some kind of life? Taking stock of everything all at once, all the theories and convos and opinions you have considered: More likely or less likely that at least one other planet would have life on it? :cowface:

I believe there are many earth-like planets in our universe the problem is if they are similar to earth planets have a life span, and old planets will likely be dead, and young planets have not developed life yet. I believe it is a given that planets like ours develop and evolve life.
 

shunyadragon

shunyadragon
Premium Member
The color of worlds indicate if they are potentially living worlds.

The Color of Habitable Worlds - Universe Today

The Color of Habitable Worlds


“This is where we live. On a Blue Dot.” said Carl Sagan when the now famous Pale Blue Dot photo was released. Captured February 14, 1990 by the Voyager 1 Space Probe, Pale Blue Dot remains the most distant photograph of the Earth ever taken at 6 billion kilometers. This past February marked the 30th anniversary of Pale Blue Dot which was reprocessed using modern digital photo techniques creating an even more remarkable image.


This updated version of the iconic “Pale Blue Dot” image taken by the Voyager 1 spacecraft uses modern image-processing software and techniques to revisit the well-known Voyager view while attempting to respect the original data and intent of those who planned the images. Credit: NASA/JPL-Caltech
Whether Pale Blue Dot, or Blue Marble, our planet is associated with the color blue. As Earth is the only inhabited world we know of, it might stand to reason that other habitable planets in space will also be blue. But it’s a little more complicated than that.

What is Color?

By “color”, astronomers mean the intensity of light at a given wavelength. Light, which is electragnetic (EM) radiation, moves like a wave through space just like ripples through water. The length of that wave determines its color. For example, EM radiation at wavelengths around 450 nanometers appear as the color blue to our eyes. But what we humans generally think of as color represents only a small portion of the overall wavelengths of the EM spectrum. Telescopes can perceive different parts of the spectrum outside of what our eyes see, such as ultraviolet or infrared, which can also be thought of as “color”. The night sky would be much brighter to our eyes if we could see the entire range of the EM spectrum. The upcoming James Webb Space Telescope can detect the infrared part of the EM spectrum. Infrared penetrates interstellar dust and gas more easily than visible light allowing James Webb to see through obstructions. Now here’s where it gets exciting – color can actually tell us a lot about an object. The color of a star relates to its surface temperature. Red stars are cooler while blue stars are hotter. Color also tells us what something is made of. The color of an atmosphere indicates what’s in the air. The color reflecting off a surface tells us what that surface is. The color arriving from an object in space is usually a blend of several colors. More than just blue, Earth is a mix of different colors each representing various surfaces and gases on our planet. Each surface or atmospheric gas leaves its unique “signature” on the wavelength of sunlight striking them resulting in a change of color. When white sunlight strikes a plant, the chlorophyll absorbs part of the sunlight for energy but reflects green and infrared light back into space. The science of this interaction between light and matter is called spectroscopy.

NASA-Jeannie-Allen.png

Colors and reflectance of various Earth surfaces c. NASA / Jeannie Allen
Wavelength-Chart.png

The EM Spectrum – note that visible light which we “see” with our eyes is a very narrow part of the spectrum.
What about a distant world – an exoplanet – around another star? The color of a distant world can tell us about its habitability. In the absence of being able to warp or hyperspace to these planets, we use information they’ve sent to us at the speed of light instead. But there are two key challenges to the spectrographic study of distant Earth-like exoplanets. First, our current generation of telescopes doesn’t have the resolution required to distinguish the light of an Earth-sized planet from that of its parent star over the vast distances we’re observing them (remember how small Earth looked at 6 billion kilometers never mind hundreds of trillions). The light of the planet and star blurs together. We know that exoplanets are out there, what size they are, if they are terrestrial worlds, and what kinds of stars they orbit, but we can see little else about them right now. Secondly, even when our telescopes are powerful enough to closely examine the light of an individual planet, we don’t have a color chart to help discern what we’re seeing out there – no point of reference. We don’t actually know what “Earth” would look like from hundreds of light years away orbiting another star. Earth itself would appear a different color under a red or blue sun. Thankfully, both challenges are being made.

Examples of future super/extreme telescope projects – Universe Today

A new generation of high-resolution telescopes is on the horizon. Space telescope missions like James Webb, HabEx, and LUVOIR; as well as land-based telescopes like the Giant Magellan Telescope will have the resolving power to separate the light of a relatively tiny dim planet from that of its titanic blazing parent star. In anticipation of this increased telescope power, Jack Madden – Ph.D. candidate in Astrophysics at Cornell University, has created a color guide of Earth-like worlds orbiting other stars. This guide, created using computer simulations, can be used to interpret the colors we’ll see from distant worlds to determine if they’re potentially habitable.
 

Left Coast

This Is Water
Staff member
Premium Member
Scotty's got it, if the election goes South he will beam me up.

Per the Star Trek timeline, we only have...43 years till we discover how to travel at light speed. :D (And make contact with intelligent aliens for the first time!)
 

Twilight Hue

Twilight, not bright nor dark, good nor bad.
What's your opinion: is it likely we'd find some kind of life? Taking stock of everything all at once, all the theories and convos and opinions you have considered: More likely or less likely that at least one other planet would have life on it? :cowface:
I can't picture one earthlike planet that is not void of some kind of life. Too bad we can't get a proper close look yet.
 

shunyadragon

shunyadragon
Premium Member
I can't picture one earthlike planet that is not void of some kind of life. Too bad we can't get a proper close look yet.

If aliens showed up to our earth in the Hadean of earth history they would find no life and world that would make Dante's Inferno look like a weeny roast.
 

Brickjectivity

Turned to Stone. Now I stretch daily.
Staff member
Premium Member
I believe there are many earth-like planets in our universe the problem is if they are similar to earth planets have a life span, and old planets will likely be dead, and young planets have not developed life yet. I believe it is a given that planets like ours develop and evolve life.
I see, so you're thinking its unlikely we'll encounter a planet anything like ours in terms of biology or culture but would probably find ones that were old and dead or undeveloped but with some sort of life.
 

Cooky

Veteran Member
Unfortunately, not close enough to escape to.....

Unless we can produce enough antimatter to use as fuel. In which case, we can reach 1G of constant acceleration, bringing us close to light speed. Halfway through, you 180 the ship, and begin deacceleration... The total time of the trip would be roughly 100 years, but for the passengers, they would age only 10 years.

...Oh, and along the way, drop off a daisy-chain of laser-beam satellites, so we can keep in constant communication.

We have 5 billion years to accomplish this, when our sun begins to swell into a red giant.
 
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shunyadragon

shunyadragon
Premium Member
If aliens visited Earth during the early Hadean Epoch they would find this planet:

This Mustafar-like lava exoplanet boasts brutal supersonic winds and vaporized rock

lava-2.jpg

Credit: Julie Roussy, McGill Graphic Design

THIS MUSTAFAR-LIKE LAVA EXOPLANET BOASTS BRUTAL SUPERSONIC WINDS AND VAPORIZED ROCK

Exoplanets, those mysterious worlds in the Milky Way that orbit stars outside our solar system, come in all sizes and flavors, from those potentially made of diamonds to planets that feature downpours of toxic iron rain. So far, NASA has identified more than 4,000 of these distant exotic destinations through various methods, some of which are extremely Earth-like and could possibly be capable of supporting life.

On the opposite end of the scale from temperate, habitable planets at the "Goldilocks" just-right zone, we present to you the hostile lava world of K2-141b and its insane atmosphere of vaporized rock, savage, supersonic winds, and massive rocky glaciers.

Now scientists have created detailed weather simulations for this radical planet in a new research paper from McGill University, York University, and the Indian Institute of Science Education published in the online journal the Monthly Notices of the Royal Astronomical Society.

Originally discovered in 2017, K2-141b is approximately 50% larger than our Big Blue Marble but orbits its star KT-141 much closer, and revolves around it several times each Earth-day with one side constantly facing the blazing solar host.
 

Heyo

Veteran Member
Until you invent warp speed, @Polymath257! Get on it! :p
Warp speed is far away if it is even possible in principle.
What we almost have is a fusion drive. That should be possible within the next 50 years. It could reach about 20% c and get its fuel from the environment. Everything else we need for a generation ship is already here.
 
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