SETI Institute

PRESS RELEASE: https://buff.ly/473FqGg Meteor Showers Shed Light on Where Comets Formed in the Early Solar System An international team of 45 researchers studying meteor showers has found that not all comets crumble the same way when they approach the Sun. In a paper published in the journal Icarus this week, they ascribe the differences to the conditions in the protoplanetary disk where comets formed 4.5 billion years ago. “The meteoroids we see as meteors in the night sky are the size of small pebbles,” said lead author and SETI Institute and NASA Ames meteor astronomer Peter Jenniskens. “They are, in fact, the same size as the pebbles that collapsed into comets during the formation of our solar system.” As our solar system formed, tiny particles in the disk around the young Sun gradually grew larger until they became the size of small pebbles. “Once pebbles grow large enough to no longer travel along with the gas, they are destroyed by mutual collisions before they can grow much bigger,” said NASA Ames planetary scientist and co-author Paul Estrada. “Comets and primitive asteroids instead were formed when clouds of these pebbles locally collapsed into kilometer-sized and larger bodies.” Fast forward 4.5 billion years: when comets approach the Sun today, they crumble into smaller pieces called meteoroids. Those meteoroids co-orbit with the comet for a while and can later create meteor showers when they hit Earth’s atmosphere. “We hypothesized that comets crumble into the sizes of the pebbles they are made of,” said Jenniskens. “In that case, the size distribution and the physical and chemical properties of young meteoroid streams still contain information about the conditions in the protoplanetary disk during this collapse.” Jenniskens and his team of professional and amateur astronomers use special low-light video cameras in networks all over the world to track meteors in a NASA-sponsored project called “CAMS” – or Cameras for Allsky Meteor Surveillance (http://cams.seti.org). “These cameras measure the meteoroids’ paths, how high they are when they first light up, and how they slow down in Earth’s atmosphere,” said Jenniskens. “Specialized cameras measured the composition of some of these meteoroids.” The team studied 47 young meteor showers. Most are the crumbs of two types of comets: Jupiter-family comets from the Scattered Disk of the Kuiper Belt beyond Neptune and long-period comets from the Oort Cloud surrounding our solar system. Long-period comets move on much wider orbits than the Jupiter-family comets and are much more loosely held by the Sun’s gravity. IMAGE: Artist's illustration of planets emerging from the dense disk of gas and dust encircling young stars. CREDIT: NASA's Goddard Space Flight Center

Another excellent day at the VLA working on the SETI Institute #COSMIC system. I invited a grad student from UNM to help me for the day. We installed another 24 x 20TB drives for storage, swapped a NIC in one of the GPU servers, and worked on troubleshooting the optical fiber connections for 3 antennas. We both also got to enjoy lunch with some of the NRAO leadership and gave them a tour of COSMIC.

Interested in joining us at GNU Radio Conference 2024, September 16-20 in Knoxville, TN? Regular pricing for registration ends tomorrow! After that, the pricing increases. #GRCon24 Register today: https://lnkd.in/gYACfhgc Learn about our keynote speakers: https://lnkd.in/eQhFwhhb

Applications for the Unistellar College Astronomy Network (UCAN) are now open for the Fall term (deadline Sunday, September 15th, 2024). Accepted members will receive a free Unistellar smart telescope for their community college institution, remote training, and access to virtual workshops showcasing educational content that can be incorporated into your classroom. Learn more: https://buff.ly/3z4eKIE #education #outreach #astronomy

#PPOD: The Microworld And now for something a "little" different. This is an actual picture of a molecule taken by IBM in 2009! The ringed structure is about 500,000 times thinner than a human hair – and you may recognize its shape. The molecule is pentacene, which consists of 22 carbon atoms and 14 hydrogen. Credit: IBM Sign up for our enews: https://buff.ly/3MoI53J

Scientists now can work out what the atmospheres of worlds outside our solar system are made of. Using the James Webb Space Telescope, we have seen water, carbon dioxide, methane, and other gases. Could we, from this distance, know how those gases formed? Possibly. Looking for planets with signs of being intentionally changed - terraforming - would give us proof of an advanced civilization, and a new paper explores just how the investigation process would work. Senior astronomer Franck Marchis talks with authors Edward W. Schwieterman and Daniel Angerhausen about what these gases would be and why they would work as evidence of life. Press release: https://lnkd.in/gr4JAu-k Paper: https://lnkd.in/gZ8hwYty

Next #SETILive: Pollution on Exoplanets? Using Greenhouse Gases as Signs of Civilization TODAY, Wednesday, Aug 28, 9:00 AM PDT / 12 PM EDT Scientists now can work out what the atmospheres of worlds outside our solar system are made of. Using the James Webb Space Telescope, we have seen water, carbon dioxide, methane, and other gases. Could we, from this distance, know how those gases formed? Possibly. Looking for planets with signs of being intentionally changed - terraforming - would give us proof of an advanced civilization, and a new paper explores just how the investigation process would work. Senior astronomer Franck Marchis talks with authors Edward W. Schwieterman and Daniel Angerhausen about what these gases would be and why they would work as evidence of life. WATCH ON YOUTUBE: https://buff.ly/4dH88Pw

When a star at its life's end explodes, a debris cloud expands away from the now-dead star. The debris forms intricate and amazing structures in the expanding cloud and can cause the formation of a variety of molecules. Using the James Webb Space Telescope, scientists have collected information regarding Cassiopeia A (Cas A), the youngest known supernova remnant in the Milky Way. The observations shed light on how molecules and dust form and are destroyed in the aftermath of an explosion. These results suggest that supernovae, like Cas A, are key sources of the dust observed in ancient galaxies. A recent paper highlights the findings of this work, including the temperatures measured and molecules formed. Deputy Director of the Carl Sagan Center Simon Steel chats with lead author Jeonghee Rho and co-authors Danny Milisavljevic and Ilse De Looze about the data collected and what it means for dust formation in the universe. Press release: https://lnkd.in/eNB8dddc Paper: https://lnkd.in/eRu94_ek

AWARD OPPORTUNITY: https://buff.ly/4cK7ZcK The SETI Forward Award was established in 2018 to support undergraduate students interested in careers in SETI and astrobiology. Each year, dozens of students intern with SETI and astrobiology scientists but most pivot to other fields, resulting in fewer talented researchers focused on the search for life beyond Earth. SETI Forward aims to bridge the gap between these internships and jobs in SETI and astrobiology research by providing $1500 per award. This year's application window is now open with a deadline of September 6. #seti #undergrad #research

https://buff.ly/3T3am3m The sky tells its own tales with stars as protagonists, planets as supporting characters, and meteor showers and comets as special effects that add sparkle to this cosmic script. Now, scientists have uncovered a new plot twist, one with meteors that shines a light on where comets formed in the early solar system. According to an international team of 45 researchers studying meteor showers, comets don’t all disintegrate alike as they approach our Sun. In a paper published in the scientific journal Icarus, they attribute these differences to varied conditions within the protoplanetary disk, the birthplace of comets nearly 4.5 billion years ago. “The meteoroids we see as meteors in the night sky are the size of small pebbles,” said lead author and SETI Institute and NASA’s Ames Research Center meteor astronomer Peter Jenniskens. “They are, in fact, the same size as the pebbles that collapsed into comets during the formation of our solar system.”