YubNub Social YubNub Social
    جستجوی پیشرفته
  • وارد شدن

  • حالت شب
  • © 2025 YubNub Social
    در باره • فهرست راهنما • با ما تماس بگیرید • توسعه دهندگان • سیاست حفظ حریم خصوصی • شرایط استفاده • Android • Apple iOS • Get Our App

    انتخاب کنید زبان

  • Bengali
  • Chinese
  • Croatian
  • Danish
  • English
  • Filipino
  • Hebrew
  • Hindi
  • Indonesian
  • Japanese
  • Korean
  • Persian
  • Swedish
  • Urdu
  • Vietnamese
Install our *FREE* WEB APP! (PWA)
حالت شب
Account
My Profile Wallet : $ 0.00 My Settings
انجمن
News Feed (Home) پست های محبوب مناسبت ها وبلاگ بازار انجمن
Media
Headline News VidWatch Game Zone Top PodCasts
Explore
Explore شغل ها ارائه می دهد
© 2025 YubNub Social
  • Bengali
  • Chinese
  • Croatian
  • Danish
  • English
  • Filipino
  • Hebrew
  • Hindi
  • Indonesian
  • Japanese
  • Korean
  • Persian
  • Swedish
  • Urdu
  • Vietnamese
در باره • فهرست راهنما • با ما تماس بگیرید • توسعه دهندگان • سیاست حفظ حریم خصوصی • شرایط استفاده • Android • Apple iOS • Get Our App
Advertisement
Stop Seeing These Ads

کشف کردن نوشته ها

Posts

کاربران

صفحات

گروه

وبلاگ

بازار

مناسبت ها

بازی ها

انجمن

شغل ها

YubNub News
YubNub News
24 که در

Polling Expert Retires Following Shockingly Wrong 2024 Election Projection
Favicon 
yubnub.news

Polling Expert Retires Following Shockingly Wrong 2024 Election Projection

J. Ann Selzer, renowned pollster behind the Iowa Poll, retires after a significant miss in the 2024 presidential election prediction. At a Glance Selzer’s final Iowa Poll incorrectly predicted Kamala…
پسندیدن
اظهار نظر
اشتراک گذاری
YubNub News
YubNub News
24 که در

Federal Court Halts Louisiana’s Ten Commandments Mandate in Public School Classrooms
Favicon 
yubnub.news

Federal Court Halts Louisiana’s Ten Commandments Mandate in Public School Classrooms

The 5th U.S. Circuit Court of Appeals has maintained a block on Louisiana’s plan to mandate the display of the Ten Commandments in public school classrooms, upholding a prior district court ruling while…
پسندیدن
اظهار نظر
اشتراک گذاری
YubNub News
YubNub News
24 که در

Play Stupid Games, Win Stupid Prizes: Business Receives Backlash After Refusing to Serve Trump Supporters
Favicon 
yubnub.news

Play Stupid Games, Win Stupid Prizes: Business Receives Backlash After Refusing to Serve Trump Supporters

At times, it can feel like the country is only concerned about all things red and blue, but if you're a business owner, you're typically only worried about another color: green (despite what Whoopi Goldberg…
پسندیدن
اظهار نظر
اشتراک گذاری
Science Explorer
Science Explorer
24 که در

What a Misplaced Meteorite Told Us About Mars
Favicon 
www.universetoday.com

What a Misplaced Meteorite Told Us About Mars

11 million years ago, Mars was a frigid, dry, dead world, just like it is now. Something slammed into the unfortunate planet, sending debris into space. A piece of that debris made it to Earth, found its way into a drawer at Purdue University, and then was subsequently forgotten about. Until 1931, when scientists studied and realized it came directly from Mars. What has it told them about the red planet? 11 million years ago, the Himalayas were rising on a warmer, more humid Earth. Early ape species made their home in an Africa covered by tropical forests. Diverse mammal species roamed the continents. At the same time, on Mars, the frigid wind blew across a desiccated, forlorn world. The planet’s thin atmosphere is a weak barrier to meteorites, and the planet’s cratered surface bears witness to its nakedness. Some impacts were powerful enough to launch debris into space beyond the planet’s gravitational pull. The meteorite in the drawer is one such piece of debris. “Many meteoroids are produced by impacts on Mars and other planetary bodies, but only a handful will eventually fall to Earth.”Marissa Tremblay, Purdue University The meteorite was long forgotten in its storage place until 1931. Scientists identified it as a piece of Mars, and now new research is uncovering clues about Mars’ past hidden in the 800-gram piece of rock. This image shows a page from an article published in Popular Astronomy in 1935. Image Credit: Popular Astronomy. 11 million years ago is not a long time in geological and planetary terms, and the number fits neatly into most people’s imaginations. But rock has deep temporal roots, and the meteorite that reached Earth is an igneous rock that dates back 1.4 billion years. That much time is more difficult to understand, but science is at its best when it opens human minds to a more fulsome understanding of nature. The meteorite, named “Lafayette” after the city in Indiana that’s home to Purdue University, is the subject of new research published in Geochemical Perspectives Letters. It’s titled “Dating recent aqueous activity on Mars,” and the lead author is Marissa Tremblay. Tremblay is an assistant professor with the Department of Earth, Atmospheric, and Planetary Sciences (EAPS) at Purdue University. There’s ample evidence that some minerals on Mars formed in the presence of water. Though Lafayette itself is an igneous rock 1.4 billion years old, some of the minerals it contains are younger. “Dating these minerals can therefore tell us when there was liquid water at or near the surface of Mars in the planet’s geologic past,” Tremblay said. “We dated these minerals in the Martian meteorite Lafayette and found that they formed 742 million years ago. We do not think there was abundant liquid water on the surface of Mars at this time. Instead, we think the water came from the melting of nearby subsurface ice called permafrost, and that the permafrost melting was caused by magmatic activity that still occurs periodically on Mars to the present day.” Lafayette is one of the Nakhlite meteorites, an igneous rock that formed from basaltic lava around 1.4 billion years ago. Scientists think these rocks formed in one of Mars’ large volcanic regions: Elysium, Syrtis Major Planum, or the largest one, Tharsis, which is home to the three shield volcanoes, Tharsis Montes. A colourized image of the surface of Mars taken by the Mars Reconnaissance Orbiter. The line of three volcanoes is the Tharsis Montes, with Olympus Mons to the northwest. Valles Marineris is to the east. The researchers think that the Lafayette meteorite came from the Tharsis volcanic region, or one of Mars’ other, smaller volcanic regions. Image: NASA/JPL-Caltech/ Arizona State University Ancient rocks and their embedded minerals contain information about Mars’ ancient past. The history of Mars’ hydrological cycle is a key objective in our ongoing study of Mars. This research is focused on a particular mineral in Lafayette called iddingsite. It forms when basalt is weathered in the presence of water. The difficulty with meteorites and the clues they contain about ancient Mars is that they’ve been exposed to and potentially altered by the heat of the initial impact and the heat of entry into Earth’s atmosphere. The chemical signals inherent in rock can become muddied. But Lafayette is different. It’s clear that it was blasted off of Mars 11 million years ago. “We know this because once it was ejected from Mars, the meteorite experienced bombardment by cosmic ray particles in outer space that caused certain isotopes to be produced in Lafayette,” Tremblay says. “Many meteoroids are produced by impacts on Mars and other planetary bodies, but only a handful will eventually fall to Earth.” “The age could have been affected by the impact that ejected the Lafayette Meteorite from Mars, the heating Lafayette experienced during the 11 million years it was floating out in space, or the heating Lafayette experienced when it fell to Earth and burned up a little bit in Earth’s atmosphere,” Tremblay said. “But we were able to demonstrate that none of these things affected the age of aqueous alteration in Lafayette.” Study co-author Ryan Ickert is a senior research scientist in Purdue’s EAPS. Ickert uses heavy radioactive and stable isotopes to study geological processes over time. He showed how isotope data used to date water-rock interactions on Mars were problematic and that the data had likely been polluted by other processes. According to Ickert, he and his colleagues got it right this time. “This meteorite uniquely has evidence that it has reacted with water. The exact date of this was controversial, and our publication dates when water was present,” he says. This figure from the research shows a cross-section of the Lafayette meteorite. Ol is an olivine grain surrounded by augite crystals (Px). Iddingsite (Id) is present in veins that travel through the rock. Though Lafayette formed over 1.3 billion years ago, the Iddingsite veins formed later, about 742 million years ago, when water seeped through the cracks. Image Credit: Tremblay et al. 2024. The researchers used a novel technique involving the isotopes Argon 40 and Argon 39 to date Lafayette’s exposure to water and its formation of Iddingsite. That showed them that the exposure occurred 742 million years ago. Their explanation is that magmatic activity melted subsurface ice, and the water subsequently found its way into cracks in the igneous rock, altering some of the olivine into Iddingsite. All this from a meteorite that was lost in a drawer. The Solar System is a puzzle. It’s an artifact of Nature’s ordered complexity, but at the same time, it’s shaped by Nature’s steadfast chaos. Each molecule, each tiny piece of rock, including the Lafayette meteorite, is a part of it. Each piece holds a clue to the puzzle. “We can identify meteorites by studying what minerals are present in them and the relationships between these minerals inside the meteorite,” said Tremblay. “Meteorites are often denser than Earth rocks, contain metal, and are magnetic. We can also look for things like a fusion crust that forms during entry into Earth’s atmosphere. Finally, we can use the chemistry of meteorites (specifically their oxygen isotope composition) to fingerprint which planetary body they came from or which type of meteorite it belongs to.” Dating these rocks, these pieces of the puzzle, is difficult. However, this research has made progress by developing a novel way to date minerals in the Lafayette meteorite. “We have demonstrated a robust way to date alteration minerals in meteorites that can be applied to other meteorites and planetary bodies to understand when liquid water might have been present,” Tremblay concluded. The post What a Misplaced Meteorite Told Us About Mars appeared first on Universe Today.
پسندیدن
اظهار نظر
اشتراک گذاری
Conservative Voices
Conservative Voices
24 که در

Trump Taps Matthew Whitaker as NATO Ambassador
Favicon 
www.theamericanconservative.com

Trump Taps Matthew Whitaker as NATO Ambassador

President-elect Donald Trump announced Wednesday his selection of Matthew Whitaker to serve as the U.S. ambassador to NATO. Whitaker served as chief of staff to Attorney General Jeff Sessions and subsequently as acting attorney general for a short period during Trump’s first presidential term, but is an outsider to the national security realm. In a statement on social media, Trump said, “Matt is a strong warrior and loyal Patriot, who will ensure the United States’ interests are advanced and defended… I look forward to working closely with him as we continue to promote PEACE THROUGH STRENGTH, Freedom, and Prosperity around the World.” The post Trump Taps Matthew Whitaker as NATO Ambassador appeared first on The American Conservative.
پسندیدن
اظهار نظر
اشتراک گذاری
Clips and Trailers
Clips and Trailers
24 که در ·Youtube Cool & Interesting

YouTube
Gust's Private Party with Joanne (Julia Roberts, Phillip Hoffman) | Charlie Wilson's War
پسندیدن
اظهار نظر
اشتراک گذاری
Clips and Trailers
Clips and Trailers
24 که در ·Youtube Cool & Interesting

YouTube
Scorpions attack!! | The Scorpion King 4 | CLIP
پسندیدن
اظهار نظر
اشتراک گذاری
RetroGame Roundup
RetroGame Roundup
24 که در ·Youtube Gaming

YouTube
Sega Model 2 Best Arcade Games of all Time (Time Stamps) #model2 #arcadegames #arcadegaming
پسندیدن
اظهار نظر
اشتراک گذاری
Conservative Voices
Conservative Voices
24 که در

Republican Revolution in Bucks County: Scott Presler Rips Commissioners Into Submission [WATCH]
Favicon 
www.rvmnews.com

Republican Revolution in Bucks County: Scott Presler Rips Commissioners Into Submission [WATCH]

Republican Revolution in Bucks County: Scott Presler Rips Commissioners Into Submission [WATCH]
پسندیدن
اظهار نظر
اشتراک گذاری
Conservative Voices
Conservative Voices
24 که در

Donald Trump Appoints Matthew Whitaker as NATO Ambassador Amid Global Tensions [WATCH]
Favicon 
www.rvmnews.com

Donald Trump Appoints Matthew Whitaker as NATO Ambassador Amid Global Tensions [WATCH]

Donald Trump Appoints Matthew Whitaker as NATO Ambassador Amid Global Tensions [WATCH]
پسندیدن
اظهار نظر
اشتراک گذاری
Showing 3106 out of 56665
  • 3102
  • 3103
  • 3104
  • 3105
  • 3106
  • 3107
  • 3108
  • 3109
  • 3110
  • 3111
  • 3112
  • 3113
  • 3114
  • 3115
  • 3116
  • 3117
  • 3118
  • 3119
  • 3120
  • 3121
Advertisement
Stop Seeing These Ads

ویرایش پیشنهاد

افزودن ردیف








یک تصویر را انتخاب کنید
لایه خود را حذف کنید
آیا مطمئن هستید که می خواهید این ردیف را حذف کنید؟

بررسی ها

برای فروش محتوا و پست های خود، با ایجاد چند بسته شروع کنید. کسب درآمد

پرداخت با کیف پول

هشدار پرداخت

شما در حال خرید اقلام هستید، آیا می خواهید ادامه دهید؟

درخواست بازپرداخت