Posts

This asteroid came from another solar system—and it’s here to stay

http://www.sciencemag.org/news/2018/05/asteroid-came-another-solar-system-and-it-s-here-stay Source:   By Daniel Clery, Science Magazine. Excerpt: While astronomers around the world had their eyes fixed last year on ‘Oumuamua, a lump of rock from another planetary system that whizzed through ours, little did they know that another interstellar interloper was quietly living among us. And this one appears to have been here for billions of years. Astronomers first spotted the object, an asteroid called 2015 BZ509 that is orbiting close to Jupiter, in 2014. They knew it was unusual because it was traveling around the solar system in the opposite direction as almost everything else. ...Astronomers have found other objects in “retrograde” orbits, perhaps knocked off course by passing too close to a giant planet, but 2015 BZ509’s orbit was the weirdest of all because it is also elongated and out of alignment with the planets and other bodies. To find out why, a pair of astronomers ran...

Yes, Pluto is a planet

https://www.washingtonpost.com/news/speaking-of-science/wp/2018/05/07/yes-pluto-is-a-planet/ Source:   David Grinspoon and Alan Stern, The Washington Post. Excerpt: Three years ago, NASA’s New Horizons, the fastest spaceship ever launched, raced past Pluto, spectacularly revealing the wonders of that newly seen world. This coming New Year’s Eve — if all goes well on board this small robot operating extremely far from home — it will treat us to images of the most distant body ever explored, provisionally named Ultima Thule. We know very little about it, but we do know it’s not a planet. Pluto, by contrast — despite what you’ve heard — is. Why do we say this? ...We use “planet” to describe worlds with certain qualities. When we see one like Pluto, with its many familiar features — mountains of ice, glaciers of nitrogen, a blue sky with layers of smog — we and our colleagues quite naturally find ourselves using the word “planet” to describe it and compare it to other planets that ...

Gaia’s Map of 1.3 Billion Stars Makes for a Milky Way in a Bottle

https://www.nytimes.com/2018/05/01/science/gaia-map-milky-way.html Source:   By Dennis Overbye, The New York Times. Excerpt: ...astronomers in Europe released a three-dimensional map of the Milky Way. It is the most detailed survey ever produced of our home galaxy. It contains the vital statistics of some 1.3 billion stars — about one percent of the entire cosmic panoply of which Earth and the sun are part. Not to mention measurements of almost half a million quasars, asteroids and other flecks in the night. Analyzing all these motions and distances, astronomers say, could provide clues to the nature of dark matter. The gravity of that mysterious substance is said to pervade space and sculpt the arrangements of visible matter. Gaia’s data could also reveal information about the history of other forces and influences on our neighborhood in the void. And it could lead to a more precise measurement of a historically troublesome parameter called the Hubble constant, which describes...

Diamonds in a Meteorite May Be a Lost Planet’s Fragments

https://www.nytimes.com/2018/04/18/science/diamonds-meteorite-lost-planet.html Source:   By Nicholas St. Fleur, The New York Times Excerpt: In 2008, chunks of space rock crashed in the deserts of Sudan. Diamonds discovered inside one of the recovered meteorites may have come from a destroyed planet that orbited our sun billions of years ago, scientists said on Tuesday. If confirmed, they say, it would be the first time anyone has recovered fragments from one of our solar system’s so-called “lost” planets. ... Dr. Gillet’s colleague Farhang Nabiei made the discovery while taking high-resolution images of a meteorite that had landed ...about a decade ago. The space rock is classified as ureilite, a type of rare meteorite that has embedded within it several different types of minerals. And inside this one, they found diamonds. The nano-sized gems were ...far from crystal clear. They were riddled with tiny imperfections, called inclusions, made of chromite, phosphate and iron-nicke...

NASA Television to Air Launch of Next Planet-Hunting Mission

https://www.nasa.gov/press-release/nasa-television-to-air-launch-of-next-planet-hunting-mission Source:   By NASA Media Advisory M18-059 Excerpt: On a mission to detect planets outside of our solar system, NASA’s Transiting Exoplanet Survey Satellite (TESS) is scheduled to launch no earlier than 6:32 p.m. EDT Monday, April 16. Prelaunch mission coverage will begin on NASA Television and the agency’s website Sunday, April 15, with three live briefings. TESS is NASA’s next step in the search for planets outside of our solar system, known as exoplanets, including those that could support life. The mission is expected to catalog thousands of planet candidates and vastly increase the current number of known exoplanets. TESS will find the most promising exoplanets orbiting relatively nearby stars, giving future researchers a rich set of new targets for more comprehensive follow-up studies, including the potential to assess their capacity to harbor life.... 

History of Mars’s Water, Seen Through the Lens of Gale Crater

https://eos.org/articles/history-of-marss-water-seen-through-the-lens-of-gale-crater Source:   By Ramin Skibba, AGU-Eos Excerpt: Past research indicates that the Red Planet may have been a very different world more than 3 billion years ago, with warmer weather, flowing rivers, lakes, and possibly even oceans of liquid water. These conditions would have been much more hospitable to nascent life-forms, if they existed. However, recent research is uncovering a different story. “There have been two competing viewpoints about the Martian climate at this time: the traditional warm-and-wet view and the view that Mars was always cold and icy,” explained Jeffrey Andrews-Hanna, a Mars-focused planetary scientist at the University of Arizona. Now, enter a third scenario: Billions of years ago, “Mars never really experienced a temperate Earth-like climate,” Andrews-Hanna added. Instead, a body of recent evidence points to an arid early Mars with pockets of wet patches.... 

NASA’s new satellite brings the search for Earthlike exoplanets closer to home

http://www.sciencemag.org/news/2018/03/nasa-s-new-satellite-brings-search-earthlike-exoplanets-closer-home Source:   By Daniel CleryMar, Science. Excerpt: Thanks to NASA's pioneering Kepler probe, we know our galaxy is teeming with exoplanets ...more than 2600 confirmed exoplanets, implying hundreds of billions in the Milky Way. The new efforts ..target Earth-size planets whose composition, atmosphere, and climate—factors in whether they might be hospitable to life—could be studied. Leading the charge is the Transiting Exoplanet Survey Satellite (TESS), a NASA mission due for launch on 16 April. The brainchild of researchers at the Massachusetts Institute of Technology (MIT) in Cambridge, the $337 million TESS project aims to identify at least 50 rocky exoplanets—Earth-size or bigger—close enough for their atmospheres to be scrutinized by the much larger James Webb Space Telescope (JWST), due for launch in 2020. ...Like Kepler, TESS finds planets by staring at stars and looking...