Innovative space weather instruments have begun to collect data

After being installed on the International Space Station, two small instruments designed and built at NASA's Jet Propulsion Laboratory in Southern California were powered on Jan.7 and began collecting data on Earth's ocean winds and atmospheric water vapor. criticisms required for meteorological and marine forecasts. Within two days, the Compact Ocean Wind Vector Radiometer (COWVR) and Temporal Experiment for Storms and Tropical Systems (TEMPEST) instruments had collected enough data to begin producing maps.

COWVR and TEMPEST launched on December 21, 2021, with SpaceX's 24th commercial refueling mission for NASA. Both instruments are microwave radiometers, which measure changes in natural microwave emissions from the Earth. Part of the US Space Force's Space Test Program-Houston 8 (STP-H8), the instruments have been designed to demonstrate that they can collect data of comparable quality to the larger instruments currently operating in orbit.

This new COWVR map shows microwave emissions from Earth at 34 gigahertz across all latitudes visible at the Space Station (52 degrees north to 52 degrees south). This particular microwave frequency provides meteorologists with information on the strength of winds on the ocean surface, the amount of water in the clouds and the amount of water vapor in the atmosphere.

If these tools continue to be successful, they will pave the way for a new era in which low-cost satellites will complement the existing fleet of meteorological satellites. Radiometers need an antenna that rotates so as to observe a wide swath of the earth's surface instead of a narrow line. In all other space microwave radiometers, not only the antenna but also the radiometer itself and the accompanying electronics rotate about 30 times per minute.

if (jQuery ("# ​​crm_srl-th_scienze_d_mh2_1") .is (": visible")) {console.log ("Edinet ADV adding zone: tag crm_srl-th_scienze_d_mh2_1 slot id: th_scienze_d_mh2"); } There are good scientific and engineering reasons for a design with so many rotating parts, but it is a challenge to keep a spacecraft stable when there is so much moving mass. In addition, the mechanism that passes power and data between the rotating and stationary sides of the instrument proved to be time-consuming and difficult to build.



Weighing in at approximately 57, 8 kilograms, COWVR has less than one-fifth the mass of the microwave radiometer used by the US military to measure ocean winds. Less than a third of its rotating mass. To avoid the need for a separate mechanism to transfer power and spinning data to stable parts, Brown has mounted everything that needs to run on a turntable.

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COWVR's companion instrument, TEMPEST, is the product of NASA's decades of investment in technology to make the more compact space-related electronics. In the mid-2010s, JPL engineer Sharmila Padmanabhan pondered what scientific goals could be achieved by packing a compact sensor into a CubeSat, a very small type of satellite often used to test new low-cost design concepts. The new measurements could provide more insight into how storms grow.

Padmanabhan's design was first pioneered in space from 2018 to last June. That CubeSat, known as TEMPEST-D ("D" for "demonstration"), measured water vapor in the atmosphere and captured images of many large hurricanes and storms. The newly deployed TEMPEST is about the size of a large cereal box and weighs less than 1.3 kilograms, with an antenna approximately 15 centimeters in diameter.

The size of the antenna dictates that TEMPEST can observe best only the shortest microwave wavelengths sensitive to water vapor, about 10 times shorter than those perceived by COWVR. A smaller antenna "matches" short wavelengths better, similar to how a flute's short air column is suitable for short wavelengths of sound (high notes), while the column long air of a tuba is better for long wavelengths of low notes.

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