Jan 7, 2024 09:10 PM
Do neutron stars have mountains? Gravitational wave observatories could detect them
https://www.universetoday.com/165080/do-...tect-them/
EXCERPTS: The surface gravity of a neutron star is so incredibly intense that it can cause atoms to collapse into a dense cluster of neutrons. The interiors of neutron stars may be dense enough to allow quarks to escape the bounds of nuclei. So it’s hard to imagine neutron stars as active bodies, with tectonic crusts and perhaps even mountains. But we have evidence to support this idea, and we could learn even more through gravitational waves.
[...] One idea is that neutron stars have a rather thin but rigid crust, similar to that of a rocky planet. As a neutron star cools over time, this crust fractures and folds, which leads to quakes, fissures, and perhaps even mountains. While this seems to be a reasonable model, it’s difficult to prove because we can only detect a glitch when something dramatic happens. Imagine trying to study the mountains of Earth when you can only capture earthquake data. But as a paper on the arXiv shows, there could be another way to study the mountains of neutron stars: gravitational waves.
Gravitational wave astronomy is still a young field, but it has already captured data from neutron stars. When neutron stars merge, they create an energetic burst of gravitational waves, similar to the way merging black holes emit a gravitational chirp. Astronomers have been able to combine gravitational wave observations of merging neutron stars with optical data to study the interiors of neutron stars. This new paper takes the idea one step further... (MORE - missing details)
New images reveal what Neptune and Uranus really look like
https://www.eurekalert.org/news-releases/1030165
INTRO: Neptune is fondly known for being a rich blue and Uranus green – but a new study has revealed that the two ice giants are actually far closer in colour than typically thought. The correct shades of the planets have been confirmed with the help of research led by Professor Patrick Irwin from the University of Oxford, which has been published today in the Monthly Notices of the Royal Astronomical Society.
He and his team found that both worlds are in fact a similar shade of greenish blue, despite the commonly-held belief that Neptune is a deep azure and Uranus has a pale cyan appearance. Astronomers have long known that most modern images of the two planets do not accurately reflect their true colours.
The misconception arose because images captured of both planets during the 20th century – including by NASA’s Voyager 2 mission, the only spacecraft to fly past these worlds – recorded images in separate colours. The single-colour images were later recombined to create composite colour images, which were not always accurately balanced to achieve a “true” colour image, and – particularly in the case of Neptune – were often made “too blue”.
In addition, the early Neptune images from Voyager 2 were strongly contrast enhanced to better reveal the clouds, bands, and winds that shape our modern perspective of Neptune.
Professor Irwin said: “Although the familiar Voyager 2 images of Uranus were published in a form closer to ‘true’ colour, those of Neptune were, in fact, stretched and enhanced, and therefore made artificially too blue.”
“Even though the artificially-saturated colour was known at the time amongst planetary scientists – and the images were released with captions explaining it – that distinction had become lost over time.”
“Applying our model to the original data, we have been able to reconstitute the most accurate representation yet of the colour of both Neptune and Uranus.” (MORE - details, no ads)
We were wrong about Neptune's color... (It looks like Uranus) ... https://youtu.be/GBXSPHhZdSc
https://www.youtube-nocookie.com/embed/GBXSPHhZdSc
https://www.universetoday.com/165080/do-...tect-them/
EXCERPTS: The surface gravity of a neutron star is so incredibly intense that it can cause atoms to collapse into a dense cluster of neutrons. The interiors of neutron stars may be dense enough to allow quarks to escape the bounds of nuclei. So it’s hard to imagine neutron stars as active bodies, with tectonic crusts and perhaps even mountains. But we have evidence to support this idea, and we could learn even more through gravitational waves.
[...] One idea is that neutron stars have a rather thin but rigid crust, similar to that of a rocky planet. As a neutron star cools over time, this crust fractures and folds, which leads to quakes, fissures, and perhaps even mountains. While this seems to be a reasonable model, it’s difficult to prove because we can only detect a glitch when something dramatic happens. Imagine trying to study the mountains of Earth when you can only capture earthquake data. But as a paper on the arXiv shows, there could be another way to study the mountains of neutron stars: gravitational waves.
Gravitational wave astronomy is still a young field, but it has already captured data from neutron stars. When neutron stars merge, they create an energetic burst of gravitational waves, similar to the way merging black holes emit a gravitational chirp. Astronomers have been able to combine gravitational wave observations of merging neutron stars with optical data to study the interiors of neutron stars. This new paper takes the idea one step further... (MORE - missing details)
New images reveal what Neptune and Uranus really look like
https://www.eurekalert.org/news-releases/1030165
INTRO: Neptune is fondly known for being a rich blue and Uranus green – but a new study has revealed that the two ice giants are actually far closer in colour than typically thought. The correct shades of the planets have been confirmed with the help of research led by Professor Patrick Irwin from the University of Oxford, which has been published today in the Monthly Notices of the Royal Astronomical Society.
He and his team found that both worlds are in fact a similar shade of greenish blue, despite the commonly-held belief that Neptune is a deep azure and Uranus has a pale cyan appearance. Astronomers have long known that most modern images of the two planets do not accurately reflect their true colours.
The misconception arose because images captured of both planets during the 20th century – including by NASA’s Voyager 2 mission, the only spacecraft to fly past these worlds – recorded images in separate colours. The single-colour images were later recombined to create composite colour images, which were not always accurately balanced to achieve a “true” colour image, and – particularly in the case of Neptune – were often made “too blue”.
In addition, the early Neptune images from Voyager 2 were strongly contrast enhanced to better reveal the clouds, bands, and winds that shape our modern perspective of Neptune.
Professor Irwin said: “Although the familiar Voyager 2 images of Uranus were published in a form closer to ‘true’ colour, those of Neptune were, in fact, stretched and enhanced, and therefore made artificially too blue.”
“Even though the artificially-saturated colour was known at the time amongst planetary scientists – and the images were released with captions explaining it – that distinction had become lost over time.”
“Applying our model to the original data, we have been able to reconstitute the most accurate representation yet of the colour of both Neptune and Uranus.” (MORE - details, no ads)
We were wrong about Neptune's color... (It looks like Uranus) ... https://youtu.be/GBXSPHhZdSc