国产三级大片在线观看-国产三级电影-国产三级电影经典在线看-国产三级电影久久久-国产三级电影免费-国产三级电影免费观看

Set as Homepage - Add to Favorites

【Free video sex Sakura Michiro】Scientists find subtle clues ancient Mars had rainy days, too

Source:Feature Flash Editor:hotspot Time:2025-07-02 09:22:12

For the past four years,Free video sex Sakura Michiro NASA's Perseverancerover has rambled over a region of Marswhere scientists say a strong river once emptied into a crater, creating a large delta. 

But for that to have happened, a lot of waterwould have gushed — something difficult to explain if the Red Planet were always frozen.

Computer simulations show that ancient Mars likely experienced regular rain and snow, which helped shape vast networks of river valleys and lakes. The distribution of these land features lines up better with precipitation models than merely the effects of melted ice caps, according to a new paperpublished in the Journal of Geophysical Research: Planets


You May Also Like

The research, performed by geologists at the University of Colorado in Boulder, argues that our planetary neighbor, on average 140 million miles away in space, was warm and wet billions of years ago, challenginga long-held belief that early Mars was mostly cold and icy. 

Most scientists agree that at least some water existed on the surface during a period about 4 billion years ago, but where the water came from has been up for debate, said Amanda Steckel, who led the studyas a doctoral student. 

"We see these valleys beginning at a large range of elevations," Steckel said in a statement. "It’s hard to explain that with just ice."

SEE ALSO: A NASA rover just exposed something on Mars that eluded orbiters Viewing Mars' topography from spaceNASA's Mars Global Surveyor spacecraft created this topographical map of a region near the planet's equator with its Mars Orbiter Laser Altimeter. Credit: NASA

The researchers created a digital version of part of Mars and tested different climate scenarios. In some computer simulations, they added widespread rain or snow. For others, they only tried melting down polar ice. Then, they used the software to simulate what would happen if that water flowed for thousands of years. 

Mashable Light Speed Want more out-of-this world tech, space and science stories? Sign up for Mashable's weekly Light Speed newsletter. By clicking Sign Me Up, you confirm you are 16+ and agree to our Terms of Use and Privacy Policy. Thanks for signing up!

Their goal was to determine whether ancient Mars may have had a more Earth-like climate, at least for a while. 

The results showed when precipitation was part of the climate, valleys and streams formed in many different regions at varying elevation points. When water came only from melted ice, the valleys mostly formed in the highlands, in close proximity to where the ice caps would have been.

The team compared the simulation data to real images from NASA spacecraft that have observed Mars from orbit. The patterns created by rain or snow more closely matched what is actually seen on the Martian surface.

Observing Mars' valley networks from spaceMars' oldest terrains appear to have eroded into branching valleys, similar to regions of Earth where rain and snow have caused runoff. Credit: NASA / JPL-Caltech / Univ. of Arizona

"Water from these ice caps starts to form valleys only around a narrow band of elevations," Steckel said. "Whereas if you have distributed precipitation, you can have valley heads forming everywhere."


Related Stories
  • A NASA rover just exposed something on Mars that eluded orbiters
  • NASA's rovers just found similar gnarly rocks on opposite sides of Mars
  • The best telescopes for gazing at stars and solar eclipses in 2024
  • Past life on Mars? Here's what new NASA evidence points to.
  • Scientists found huge beaches on Mars likely from a long gone ocean

Today, snow occasionally falls on Mars, but only in the coldest extremes, according to NASA: at the poles and under cloud cover at night. So far there's no photographic evidence of Martian snowfall — clouds obscure the cameras on spacecraft — but other instruments are capable of detecting it. 

The Mars Reconnaissance Orbiter, for example, has the Mars Climate Sounder, which has collected data on carbon dioxide snow — aka dry ice — as it fell to the ground. The Phoenix landeralso used a laser-based tool to spot snow made of water near the Martian north pole in 2008. 

The team still doesn't fully grasp how Mars could have stayed warm enough for rain or snow, especially since the young sunwas about 25 percent dimmer than it is today. Despite the mystery, geologist and study coauthor Brian Hynek says without rain, landforms like Perseverance's Jezero Craterjust don't make sense. The dried delta, for example, features scattered boulders. 

"You’d need meters deep of flowing water to deposit those kinds of boulders," he said. 

0.1548s , 14256.84375 kb

Copyright © 2025 Powered by 【Free video sex Sakura Michiro】Scientists find subtle clues ancient Mars had rainy days, too,Feature Flash  

Sitemap

Top 主站蜘蛛池模板: 动漫3d精品一区二区三区乱码 | 国产精品中文字幕亚洲欧美 | 国产激情一区二区三区在线hd | 亚洲午夜精品一区二区三区 | 亚洲国产无套无码av电影 | 午夜a | 亚洲观看视频一级精品 | 亚洲av无码成h人动漫 | 国产品无码一区二区三区 | 久久伊人精品影院一本到综合 | 在线亚洲AV不卡一区二区 | 蜜芽变态另类国产日韩在线观看 | 日本乱码卡一卡二新区网站 | 国产成人无码免费看视频软件 | 中中文日产幕无线码 | 国产熟妇另类久久久久婷婷 | 欧美另类久久久精品 | 久久免费看少妇高潮A片JA小说 | 黄网站在线播放 | 无码强姦精品一区二区三区黑人 | 丰满人妻无码AV一区二区免费 | 欧美亚洲在线播放 | a一片女人一区二区三区 | 久久精品国产成人午夜福利 | 成人日韩欧美 | 欧美日韩人妻精品一区二区三 | 亚洲成人网站在线观看播放 | 亚洲日本中文字幕区 | 日本欧美黄色 | 91麻豆精品一二三区在线国语 | 国产日韩精品一区在线观看播放 | 日本国产精品无码字幕在线观看 | 欧美重口另类在线播放 | 国产精品三级手机在线观看 | 深夜福利视频导航 | 国产成人久久精品麻豆一区 | 欧美大肥婆大肥BBBBB | 国产成人99久久亚洲综合精品 | 国产日韩久久三级精品综合 | 午夜一区二区免费视频 | 人妻少妇精品中文字幕av蜜桃 |