& çâÌæÚUæð´ ·¤è ¥ôÚU Îð¹Ùæ ÁæÚUè ÚU¹ð´ ¥ÍæüÌ ¥ÂÙð ÜÿØ ÂÚU ŠØæÙ ÚU¹ð´Ð ãæÚU Ù ×æÙð´, €UØô´ç·¤ ·¤æ× ·¤ÚUÙð âð ¥æÂ·¤ô ©gðàØ ·¤è Âýæç# ãôÌè ãñ ¥õÚU ÁèßÙ ·¤æ ¹æÜèÂÙ ÎêÚU ãôÌæ ãñÐ ÖÜð ãè ÁèßÙ ×ð´ ç·¤ÌÙè Öè ·¤çÆÙæ§ü €UØô´ Ù ¥æ°, çÁ™ææâæ ¥õÚU ©ˆâæã ÕÙæ° ÚU¹ð´Ð ŠØæÙ ÚU¹ð´, ÜÿØ ã×ðàææ ¥æÂ·Ô¤ Âæâ ãôÌð ãñ´ çÁ‹ãð´ ÂæÙð ·Ô¤ çÜ° ÂýØæâ ¥æÂ ·¤Öè Öè àæéM¤ ·¤ÚU â·¤Ìð ãñ´Ð

Pluto has 'Earth-like characteristics': study

Cnn Online
Nearly three years after Nasa's New Horizons spacecraft flew past Pluto, we're still learning about the dwarf planet.
A study published Thursday in the journal Science reveals that the dwarf planet has dunes. But these aren't like sand dunes on Earth; Pluto's dunes are made from solid methane ice grains.
Within our solar system, dunes are more rare than you might think. They exist on Earth, Mars, Venus, Saturn's moonTitan and Comet 67P.
"When we first saw the New Horizons images, we thought instantly that these were dunes but it was really surprising because we know there is not much of an atmosphere, "Jani Radebaugh, study co-author and associate professor in geological sciences at Brigham Young University, said in a statement.
"However despite being 30 times further away from the sun as the Earth, it turns out Pluto still has Earth-like characteristics. We have been focusing on what's dose to us, but there's a wealth of information in the distant reaches of the solar system too."
An international team of planetary scientists, physicists and geographers looked at detailed photos of Pluto's surface, captured by New Horizons, that offered a bird's eye view of the dwarf planet's active surface. It is composed of nitrogen, carbon dioxide, water and methane, and it's diverse in landforms, including plains, trenches and mountain ranges.
They saw 357 regularly spaced pale ridges and six darker wind streaks across 46 miles of the Sputnik Planitia, a sprawling ice plain that makes up one of Pluto's largest surface features. The scientists noticed that the ridges ran parallel with a major mountain range, that seemed to shift and spread out. They also change locally and consistently. This indicated that wind was creating the ridges.
But with the surface frozen, the researchers wondered what it could be made of.
Combining an analysis of wind streak and dune-like features with
spectral and numerical modelling, the scientists determined what might be the underlying architect of dunes on Pluto.
Wind could create the dunes out of fine particles once they're airborne. And since Pluto's surface pressure is 100,000 times lower than Earth's, those grains don't need as much of a lift.
They discovered that was possible if there was sublimation at the surface, when a solid is turned directly into a gas. In Pluto’s case, the sun heats the icy surface enough that gas can be released into the atmosphere. This also lifts the methane particles, which mostly likely come from the nearby mountains. But the researchers haven't ruled out that these could be made of nitrogen ice.
Pluto's winds can reach 18 to 24 miles per hour, creating and sculpting dunes.
"On Earth, you need a certain strength of wind to release sand particles into the air, but winds that are 20% weaker are then sufficient to maintain transport," Eric Parteli, study coauthor and lecturer in computational geosciences at the University of Cologne, said in a statement.