NASA Astronomy Picture of the Day

August 21, 2025

Mostly Perseids

In this predawn skyscape recorded during the early morning hours of August 13, mostly Perseid meteors are raining down on planet Earth. You can easily identify the Perseid meteor streaks. They're the ones with trails that seem to converge on the annual meteor shower's radiant, a spot in the heroic constellation Perseus, located off the top of the frame. That's the direction in Earth's sky that looks along the orbit of this meteor shower's parent, periodic Comet Swift-Tuttle. Of course the scene is a composite, a combination of about 500 digital exposures to capture meteors registered with a single base frame exposure. But all exposures were taken during a period of around 2.5 hours from a wind farm near Mönchhof, Burgenland, Austria. Red lights on the individual wind turbine towers dot the foreground. In their spectacular close conjunction, bright planets Jupiter and Venus are poised above the eastern horizon.

https://apod.nasa.gov/apod/astropix.html

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waterfowl

https://science.nasa.gov/science-research/earth-science/steve-platnick-steps-down-from-nasa-after-34-years-of-service/

Steve Platnick Steps Down from NASA After 34 Years of Service

Aug 20, 2025

Dr. Steven “Steve” Platnick has taken the NASA Deferred Resignation Program (DRP). His last work day was August 8, 2025. Steve spent more than three decades at, or associated with, NASA.

While he began his civil servant career at NASA’s Goddard Space Flight Center (GSFC) in 2002, his Goddard association went back to 1993, first as a contractor and then as one of the earliest employees of the Joint Center for Earth Systems Technology (JCET), a cooperative agreement between the University of Maryland, Baltimore County (UMBC) and GSFC’s Earth Science Division. At JCET Steve helped lead the development of the Atmosphere Physics Track curricula.

Previously, he held a National Research Council (NRC) post-doctoral fellow at NASA’s Ames Research Center.

Along with his research work on cloud remote sensing from satellite and airborne sensors, Steve served as the Deputy Director for Atmospheres in GSFC’s Earth Sciences Division from January 2015–July 2024.

During his time at NASA, Steve played an integral role in the sustainability and advancement of NASA’s Earth Observing System platforms and data.

In 2008, he took over as the Earth Observing System (EOS) Senior Project Scientist from Michael King. In this role, he led the EOS Project Science Office, which included support for related EOS facility airborne sensors, ground networks, and calibration labs.

The office also supported The Earth Observer newsletter, the NASA Earth Observatory, and other outreach and exhibit activities on behalf of NASA Headquarters’ Earth Science Division and Science Mission Directorate (further details below).

From January 2003– February 2010, Steve served as the Aqua Deputy Project Scientist.

Improving Imager Cloud Algorithms

Steve was actively involved in the Moderate Resolution Imaging Spectroradiometer (MODIS) Science Team serving as the Lead for the MODIS Atmosphere Discipline Team (cloud, aerosol and clear sky products) since 2008 and as the NASA Suomi National Polar-orbiting Partnership (Suomi NPP)/JPSS Atmosphere Discipline Lead/co-Lead from 2012–2020.

His research team enhanced, maintained, and evaluated MODIS and Visible Infrared Imaging Radiometer Suite (VIIRS) cloud algorithms that included Level-2 (L2) Cloud Optical/Microphysical Properties components (MOD06 and MYD06 for MODIS on Terra and Aqua, respectively) and the Atmosphere Discipline Team Level-3 (L3) spatial/temporal products (MOD08, MYD08). The L2 cloud algorithms were developed to retrieve thermodynamic phase, optical thickness, effective particle radius, and derived water path for liquid and ice clouds, among other associated datasets.

Working closely with longtime University of Wisconsin-Madison colleagues, the team also developed the CLDPROP continuity products designed to bridge the MODIS and VIIRS cloud data records by addressing differences in the spectral coverage between the two sensors; this product is currently in production for VIIRS on Suomi NPP and NOAA-20, as well as MODIS Aqua.

The team also ported their CLDPROP code to Geostationary Operational Environmental Satellites (GOES) R-series Advanced Baseline Imager (ABI) and sister sensors as a research demonstration effort.

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Steve’s working group participation included the Global Energy and Water Exchanges (GEWEX) Cloud Assessment Working Group (2008–present); the International Cloud Working Group (ICWG), which is part of the Coordination Group for Meteorological Satellites (CGMS), and its original incarnation, the Cloud Retrieval Evaluation Working (CREW) since 2009; and the NASA Observations for Modeling Intercomparison Studies (obs4MIPs) Working Group (2011–2013).

Other notable roles included Deputy Chair of the Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) Science Definition Team (2011–2012) and membership in the Advanced Composition Explorer (ACE) Science Definition Team (2009–2011), the ABI Cloud Team (2005–2009), and the Climate Absolute Radiance and Refractivity Observatory (CLARREO) Mission Concept Team (2010–2011).

Steve has participated in numerous major airborne field campaigns over his career.

His key ER-2 flight scientist and/or science team management roles included the Monterey Area Ship Track experiment (MAST,1994), First (International Satellite Cloud Climatology Project (ISCCP) Regional Experiment - Arctic Cloud Experiment [FIRE-ACE, 1998], Southern Africa Fire-Atmosphere Research Initiative (SAFARI-2000), Cirrus Regional Study of Tropical Anvils and Cirrus Layers – Florida Area Cirrus Experiment (CRYSTAL-FACE, 2002), and Tropical Composition, Cloud and Climate Coupling (TC4, 2007).

Supporting Earth Science Communications

Through his EOS Project Science Office role, Steve has been supportive of the activities of NASA’s Science Support Office (SSO) and personally participated in many NASA Science exhibits at both national and international scientific conferences, including serving as a Hyperwall presenter numerous times.

For The Earth Observer newsletter publication team in particular, Steve replaced Michael King as Acting EOS Senior Project Scientist in June 2008, taking over the authorship of “The Editor’s Corner” beginning with the May–June 2008 issue [Volume 20, Issue 3].

The Acting label was removed beginning with the January–February 2010 issue [Volume 22, Issue 1].

Steve has been a champion of continuing to retain a historical record of NASA science team meetings to maintain a chronology of advances made by different groups within the NASA Earth Science community.

He was supportive of the Executive Editor’s efforts to create a series called “Perspectives on EOS,” which ran from 2008–2011 and told the stories of the early years of the EOS Program from the point of view of those who lived them.

He also supported the development of articles to commemorate the 25th and 30th anniversary of The Earth Observer.

Later, Steve helped guide the transition of the newsletter from a print publication – the November–December 2022 issue was the last printed issue – to fully online by July 2024, a few months after the publication’s 35th anniversary.

The Earth Observer team will miss Steve’s keen insight, historical perspective, and encouragement that he has shown through his leadership for the past 85 issues of print and online publications.

A Career Recognized through Awards and Honors

Throughout his career, Steve has amassed numerous honors, including the Goddard William Nordberg Memorial Award for Earth Science in 2023 and the Verner E. Suomi Award from the American Meteorological Society (AMS) in 2016.

He was named an AMS Fellow that same year. He received two NASA Agency Honor Awards – the Exceptional Achievement Medal in 2008 and the Exceptional Service Medal in 2015.

Steve received his bachelor’s degree and master’s degree in electrical engineering from Duke University and the University of California, Berkeley, respectively. He earned a Ph.D. in atmospheric sciences from the University of Arizona.

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