Keeping time (4/6/23)

Good afternoon, and happy Thursday. Whatever you celebrate, I hope you have a very happy holiday this week.

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Keeping up the TEMPO

In the wee hours of the morning tomorrow, NASA is planning to launch a small payload to take daily measurements of pollution across North America for the first time.

The instrument, called TEMPO (Tropospheric Emissions Monitoring of Pollution), is hitching a ride to space aboard the Intelsat 40E satellite, which is launching on a dedicated Falcon 9 from Cape Canaveral at 12:29am.

Monitoring pollution: TEMPO is headed to a geostationary (GEO) perch that gives it a view of the entire continental US, as well as parts of Mexico and Canada, all at once. Once per hour, the instrument will take an East-to-West scan of that whole region, hunting for polluting gasses. It has image resolution down to a few square miles per pixel—much sharper than current capabilities that resolve down to ~100 sq mi per pixel.

At its core, TEMPO is a grating spectrometer. That means that “it measures the Sun that’s reflected off the Earth’s atmosphere and separates it into about 2,000 component wavelengths,” Dennis Nicks, director of payload engineering at Ball Aerospace, which manufactured TEMPO, said on a press call.

“The scientists at SAO [the Smithsonian Astrophysical Observatory] then use these hyperspectral data to determine the concentration of trace gasses in the atmosphere.”

TEMPO will be the second of three instruments that monitor pollution activity over the Northern Hemisphere. The first, GEMS, is already in operation over Asia. ESA is currently working on building its Sentinel-4 satellite, which will provide the same capability over Europe and extend pollution monitoring over most of the land area in the Northern Hemisphere.

Keeping it cheap: In recent years, the government—NASA included—has been seeking out ways to take advantage of the technological progress in the commercial space industry to advance its own projects. Since TEMPO is riding on Intelsat 40E, NASA paid a whole lot less for construction and launch than it would have by building and launching its own independent satellite.

The decrease in cost of building smallsats, increased availability of hosted payload services, and the dramatic drop in launch costs over the past decade open the opportunity for an exciting new era of space exploration and science.

Other News from the Cosmos

• NASA is planning to launch two super-pressured balloons from New Zealand this month, testing a new method to study space from above most of Earth’s atmosphere.

• Rivers develop and change over time with shifts in rainfall and erosion. Researchers at the Chinese Academy of Sciences used four decades of Landsat data to track water extent variations in rivers over time.

• The Perseus cloud, a very young star cluster, contains bunches of molecules important for the formation of life, including water, carbon dioxide, and amino acids.

• Lightweight mirrors for use in future space telescopes have been developed by scientists at the Max Planck Institute for Extraterrestrial Physics in Germany.

• The Hubble tension—the conflict between two different measurements of the expansion of the universe—has long stumped astronomers. A study from EPFL’s Institute of Physics calibrated a new “yardstick” to help understand that rate.

• The structure of galaxy clusters has pointed to new evidence to support the standard model of cosmology, which describes the distribution of matter, dark matter, and energy in the universe since the Big Bang.

• A pair of quasars, or very energetic black holes accumulating material very quickly, was spotted from a time when the universe was ~3 billion years old.

• The Planetary Society is leading a call to save (i.e., reprioritize) NASA’s VERITAS mission to Venus.

The View from Space

JWST has done it again with this striking view of Uranus, showing details of the ice giant's rings and a bright splotch on its left side, potentially showing storm activity.

Personally, I can't stop looking at the wide view, where you can pick out six of the planet's 27 moons: