How Are We Made of Star Stuff? We Asked a NASA Expert: Episode 58

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https://youtu.be/63uNNcCpxHI

How are we made of star stuff?

Well, the important thing to understand about this question is that it’s not an analogy, it’s literally true.

The elements in our bodies, the elements that make up our bones, the trees we see outside, the other planets in the solar system, other stars in the galaxy. These were all part of stars that existed well before our Sun and Earth and solar system were even formed.

The universe existed for billions of years before we did. And all of these elements that you see on the periodic table, you see carbon and oxygen and silicon and iron, the common elements throughout the universe, were all put there by previous generations of stars that either blew off winds like the Sun blows off a solar wind, or exploded in supernova explosions and thrust their elements throughout the universe.

These are the same things that we can trace with modern telescopes, like the Hubble Telescope and the James Webb Space Telescope, the Chandra X-ray Observatory. These are all elements that we can map out in the universe with these observatories and trace back to the same things that form us and the elemental abundances that we see in stars now are the same things that we see in the Earth’s crust, we see in asteroids. And so we know that these are the same elements that were once part of these stars.

So the question of, “How are we made of star stuff?”, in the words of Carl Sagan, “The cosmos is within us. We are made of star stuff. We are a way for the universe to know itself.”

[END VIDEO TRANSCRIPT]

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NASA Tracks Snowmelt to Improve Water Management

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As part of a science mission tracking one of Earth’s most precious resources – water – NASA’s C-20A aircraft conducted a series of seven research flights in March that can help researchers track the process and timeline as snow melts and transforms into a freshwater resource. The agency’s Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) installed on the aircraft collected measurements of seasonal snow cover and estimate the freshwater contained in it.
“Seasonal snow is a critical resource for drinking water, power generation, supporting multi-billion dollar agricultural and recreation industries,” said Starr Ginn, C-20A project manager at NASA’s Armstrong Flight Research Center in Edwards, California.  “Consequently, understanding the distribution of seasonal snow storage and subsequent runoff is essential.”
The Dense UAVSAR Snow Time (DUST) mission mapped snow accumulation over the Sierra Nevada mountains in California and the Rocky Mountains in Idaho. Mission scientists can use these observations to estimate the amount of water stored in that snow.

“Until recently, defining the best method for accurately measuring snow water equivalent (SWE) – or how much and when fresh water is converted from snow – has been a challenge,” said Shadi Oveisgharan, principal investigator of DUST and scientist at NASA’s Jet Propulsion Laboratory in Southern California. “The UAVSAR has been shown to be a good instrument to retrieve SWE data.”
Recent research has shown that snow properties, weather patterns, and seasonal conditions in the American West have been shifting in recent decades. These changes have fundamentally altered previous expectations about snowpack monitoring and forecasts of snow runoff. The DUST mission aims to better track and understand those changes to develop more accurate estimates of snow-to-water conversions and their timelines.
“We are trying to find the optimum window during which to retrieve snow data,” Oveisgharan said. “This estimation will help us better estimate available fresh snow and manage our reservoirs better.”

The DUST mission achieved a new level of snow data accuracy, which is partly due to the specialized flight paths flown by the C-20A. The aircraft’s Platform Precision Autopilot (PPA) enables the team to fly very specific routes at exact altitudes, speeds, and angles so the UAVSAR can more precisely measure terrain changes.
“Imagine the rows made on grass by a lawn mower,” said Joe Piotrowski Jr., operations engineer for NASA Armstrong’s airborne science program. “The PPA system enables the C-20A to make those paths while measuring terrain changes down to the diameter of a centimeter.” Läs mer…

NASA’s SPHEREx Team To Ring New York Stock Exchange Bell

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Members of the team behind NASA’s newest space telescope will ring the New York Stock Exchange closing bell in New York City at 4 p.m. EDT on Tuesday, April 22. The team helped build, launch, and operates NASA’s SPHEREx (Spectro-Photometer for the History of the Universe, Epoch of Reionization and Ices Explorer) mission to explore the origins of the universe. The New York Stock Exchange will share a recording of the closing bell ceremony on YouTube after the event.
After launching March 11 from Vandenberg Space Force Base in California on a SpaceX Falcon 9 rocket, SPHEREx will soon begin collecting data on more than 450 million galaxies and 100 million stars in the Milky Way, to improve our understanding of how the universe evolved and search for key ingredients for life in our galaxy. The observatory’s first images confirmed all of the telescope’s systems are working as expected, as the team prepares SPHEREx to begin mapping the entire sky.
Bell ringers from NASA’s Jet Propulsion Laboratory, which manages the mission, will be joined by team members from BAE Systems Inc., Space & Mission Systems, which built the telescope and spacecraft’s main structure, known as a bus, for NASA.
For more information on SPHEREx, visit:
https://www.nasa.gov/spherex
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Alise FisherHeadquarters, Washington202-358-1100alise.m.fisher@nasa.gov
Calla CofieldJet Propulsion Laboratory, Pasadena, Calif.626-808-2469calla.e.cofield@jpl.nasa.gov Läs mer…