Oct 15, 2026 04:49 AM
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This NASA Mars rover just smashed the record for distance travelled on a planet beyond Earth
https://www.skyatnightmagazine.com/news/...-travelled
INTRO: NASA’s Perseverance rover, which has been exploring the surface of Mars since 2020, has now travelled further than any other off-world vehicle, beating the previous record set by the now-defunct Opportunity rover by 40 metres (131 feet). Opportunity racked up a total of 45.16km (28.06 miles) in the years 2004 to 2018. Perseverance, in contrast, has only been on the Martian surface for six years, and continues to explore.
That means the new distance record of 45.2km (28.09 miles), which it set while travelling through a region of the Jezero Crater called Lac De Charmes on the 2,006th Martian day of its mission, is unlikely to be bettered for some time to come.
This marked improvement in rover performance can largely be attributed to Perseverance’s advanced autonomous navigation system, known imaginatively as AutoNav. This system creates a 3D map of the Martian surface as it drives, and can identify any hazards and calculate its own best route from point A to point B as it goes along.
The rover was otherwise dependent on human instructions sent from Earth. Perseverance, on the other hand, has used AutoNav for 90% of its journeys.
Steven Lee of NASA’s Jet Propulsion Laboratory, who is project manager for both the Perseverance and Curiosity rovers, says: "The original mission called for no more than 12.4 miles of driving. We’ve blown well past that, and with all mobility systems fully operational and favorable extended-ground-life test results, we expect Perseverance to keep adding to this record for many years to come."
Mark Maimon, Perseverance’s deputy team leader for robotic operations, adds that the team are currently working to improve the rover’s navigation software, which is dependent on camera images. If they can eliminate the problem of glare from sunlight, rovers would no longer need to cease operations by mid-afternoon, as they currently do when travelling towards the Sun.
This would mean rovers would have a longer effective working day, be able to travel even further, and so would be able to gather more geological data... (MORE - details)
Green, pink & purple: astronomers reveal surprising true colors of white dwarf stars
https://www.eurekalert.org/news-releases/1147389
INTRO: University of Warwick astronomers have shown that white dwarf stars can glow in a remarkable range of colours, including the first star ever found that would appear green to the human eye.
For most stars, colour is a guide to temperature. Cooler stars look orange, stars like our Sun look white, and the hottest glow pale blue, much like a blacksmith’s iron glowing red, then orange, then white-hot as it heats up. White dwarf stars, the dense remnants left behind when Sun-like stars reach the end of their lives, were thought to follow the same rule. They earned their name because the earliest examples found were surprisingly hot and glowed white/pale blue. But are orange, white and blue the only colours a star in the night sky can be?
The answer, according to new research from the University of Warwick, is no. Published in the journa RAS Techniques and Instruments (RASTI), the new study shows that if we could view them up close, certain white dwarf stars would shine in colours such as green, pink, cyan, yellow and purple.
“Most stars, including most white dwarfs, behave like ‘perfect radiators,’ so their colour is set almost entirely by temperature. But nobody had really looked into what else might be possible for white dwarfs,” said Dr Mark Hollands, Warwick Prize Fellow in the Astronomy and Astrophysics Group, University of Warwick, who led the work. “It turns out these incredibly dense stars can produce colours nobody expected, and some of them genuinely surprised me."
Why white dwarfs break the rule. The key is density. The coolest white dwarf atmospheres can reach around 1 gram per cubic centimetre, roughly the density of water and millions of times denser than the Sun’s photosphere. In these conditions, any trace elements that may be present, such as carbon, calcium and sodium, interact with the surrounding dense helium plasma and absorb light across a wider range of colours than they would at lower densities. This shifts a star’s colour away from the orange, white and blue of a perfect radiator.
No white dwarf star is close enough for its colour to be seen directly, so the team calculated it instead from data astronomers already collect routinely: a star's spectrum, the ‘fingerprint’ produced when starlight is split apart by wavelength, much like a prism splits sunlight into a rainbow. Running these spectra through a model of human colour vision revealed what colour each star's light would appear as to the eye. It is a reminder of just how much a spectrum can reveal: not just a star's temperature or its chemical makeup, but its true colour as well... (MORE - no ads)
https://www.skyatnightmagazine.com/news/...-travelled
INTRO: NASA’s Perseverance rover, which has been exploring the surface of Mars since 2020, has now travelled further than any other off-world vehicle, beating the previous record set by the now-defunct Opportunity rover by 40 metres (131 feet). Opportunity racked up a total of 45.16km (28.06 miles) in the years 2004 to 2018. Perseverance, in contrast, has only been on the Martian surface for six years, and continues to explore.
That means the new distance record of 45.2km (28.09 miles), which it set while travelling through a region of the Jezero Crater called Lac De Charmes on the 2,006th Martian day of its mission, is unlikely to be bettered for some time to come.
This marked improvement in rover performance can largely be attributed to Perseverance’s advanced autonomous navigation system, known imaginatively as AutoNav. This system creates a 3D map of the Martian surface as it drives, and can identify any hazards and calculate its own best route from point A to point B as it goes along.
The rover was otherwise dependent on human instructions sent from Earth. Perseverance, on the other hand, has used AutoNav for 90% of its journeys.
Steven Lee of NASA’s Jet Propulsion Laboratory, who is project manager for both the Perseverance and Curiosity rovers, says: "The original mission called for no more than 12.4 miles of driving. We’ve blown well past that, and with all mobility systems fully operational and favorable extended-ground-life test results, we expect Perseverance to keep adding to this record for many years to come."
Mark Maimon, Perseverance’s deputy team leader for robotic operations, adds that the team are currently working to improve the rover’s navigation software, which is dependent on camera images. If they can eliminate the problem of glare from sunlight, rovers would no longer need to cease operations by mid-afternoon, as they currently do when travelling towards the Sun.
This would mean rovers would have a longer effective working day, be able to travel even further, and so would be able to gather more geological data... (MORE - details)
Green, pink & purple: astronomers reveal surprising true colors of white dwarf stars
https://www.eurekalert.org/news-releases/1147389
INTRO: University of Warwick astronomers have shown that white dwarf stars can glow in a remarkable range of colours, including the first star ever found that would appear green to the human eye.
For most stars, colour is a guide to temperature. Cooler stars look orange, stars like our Sun look white, and the hottest glow pale blue, much like a blacksmith’s iron glowing red, then orange, then white-hot as it heats up. White dwarf stars, the dense remnants left behind when Sun-like stars reach the end of their lives, were thought to follow the same rule. They earned their name because the earliest examples found were surprisingly hot and glowed white/pale blue. But are orange, white and blue the only colours a star in the night sky can be?
The answer, according to new research from the University of Warwick, is no. Published in the journa RAS Techniques and Instruments (RASTI), the new study shows that if we could view them up close, certain white dwarf stars would shine in colours such as green, pink, cyan, yellow and purple.
“Most stars, including most white dwarfs, behave like ‘perfect radiators,’ so their colour is set almost entirely by temperature. But nobody had really looked into what else might be possible for white dwarfs,” said Dr Mark Hollands, Warwick Prize Fellow in the Astronomy and Astrophysics Group, University of Warwick, who led the work. “It turns out these incredibly dense stars can produce colours nobody expected, and some of them genuinely surprised me."
Why white dwarfs break the rule. The key is density. The coolest white dwarf atmospheres can reach around 1 gram per cubic centimetre, roughly the density of water and millions of times denser than the Sun’s photosphere. In these conditions, any trace elements that may be present, such as carbon, calcium and sodium, interact with the surrounding dense helium plasma and absorb light across a wider range of colours than they would at lower densities. This shifts a star’s colour away from the orange, white and blue of a perfect radiator.
No white dwarf star is close enough for its colour to be seen directly, so the team calculated it instead from data astronomers already collect routinely: a star's spectrum, the ‘fingerprint’ produced when starlight is split apart by wavelength, much like a prism splits sunlight into a rainbow. Running these spectra through a model of human colour vision revealed what colour each star's light would appear as to the eye. It is a reminder of just how much a spectrum can reveal: not just a star's temperature or its chemical makeup, but its true colour as well... (MORE - no ads)