AMASS—The Airborne Multiangle Aerosol Size Spectrometer Transforming Our View of Atmospheric Particles

It’s no secret in the atmospheric science community: accurate aerosol sizing data is vital for understanding our planet’s climate, weather, air quality, and more. Yet, historically, high-fidelity measurements of airborne particles—especially in the smallest size ranges—have been challenging. Enter the Airborne Multiangle Aerosol Size Spectrometer (AMASS), our response to the continued demand for next-generation aerosol instrumentation. Supported by a NASA Phase II SBIR award, AMASS is a highly innovative R&D effort aimed at helping researchers see a clearer picture of Earth’s atmosphere.

Aerosols can scatter or absorb sunlight, seed or suppress cloud formation, and influence everything from regional weather patterns to global climate models. Much of this behavior hinges on particle size. Existing under-wing or pylon-mounted instruments (e.g., legacy probes based on decades-old designs) have served us well, but many are nearing obsolescence. Researchers face limited availability of spare parts, aging optical configurations, or constraints on accurately measuring both submicron and coarser particles in flight. AMASS was conceived to fill that gap, providing a modern optical system that expands measurement capabilities, improves detection limits, and reduces reliance on soon-to-be-discontinued components (like helium-neon lasers). By giving scientists robust tools to accurately measure particle size distributions, AMASS will empower future airborne campaigns to chase everything from dust storms to urban pollution plumes with improved clarity.

What Makes AMASS Different

1. Light Scattering Measurement Method
   • AMASS uses an integrated side-scattering (ISS) approach to measure submicron aerosols accurately, potentially down to sub-100 nm. This improves on older designs that struggle with the transition between different size regimes.
2. Robust Flow and Inlet Design
   • Poorly characterized inlet flows can distort aerosol size measurements significantly. Our Phase II development emphasizes sheath-flow nozzles and isokinetic external inlets, carefully modeled using computational fluid dynamics. That way, the sample stream remains well-defined—essential for good data quality.
3. High-Speed Electronics and Data Analysis
   • Older probes often output raw signals requiring large, external data systems. By contrast, AMASS’s custom electronics (including high-speed photomultiplier sampling and FPGA/embedded solutions) will handle real-time data processing and reduce complexity.
   • Our companion software will let users see real-time particle size distributions and housekeeping data, making in-field operations far simpler.
4. Designed for Reliability
   • AMASS will fit into standard under-wing or pylon-mounted canisters (often referred to as PMS canisters). This ensures the probe is immediately compatible with most research aircraft worldwide.
   • From anti-ice systems to a sealed optical layout with purge flows to eliminate stray particles, we’ve thought through the big pain points that hamper older-generation instruments.

Current Status and What’s Next

• Prototyping & Lab Validation: We are currently refining our optical design, testing new nozzles, and verifying performance with carefully generated aerosol standards in the lab.
• Environmental Testing: Next, we’ll bring AMASS to a specialized wind tunnel to run it through icing, high-speed airstreams, and temperature extremes. This step ensures that, once on an aircraft, AMASS remains stable and precise.
• Collaboration Opportunities: We aim to make AMASS a community-driven project. If you’re developing specialized field campaigns or need advanced airborne measurements, we’d love to hear from you and explore ways to partner.

Why It Matters for Climate, Air Quality, and Beyond

From validating satellite data to studying urban pollution, airborne aerosol measurements are indispensable for bridging data gaps. AMASS’s next-generation approach will support scientists in:

• Reducing Model Uncertainty: More accurate size distributions mean better inputs for climate and chemical transport models.
• Tailoring Measurement Campaigns: Comprehensive data sets on coarse-mode or submicron aerosols can be captured in real time.
• Improving Instrument Reliability: By using more modern laser sources and improved electronics, we can significantly reduce downtime that has historically plagued older instruments.

We believe AMASS marks a significant leap forward in airborne aerosol research instrumentation. By delivering high-resolution size data in real flight conditions, we aim to help scientists, policymakers, and industry professionals better understand and manage aerosol impacts on weather, climate, and air quality. As we move closer to flight-ready demonstrations, keep an eye on our updates—and feel free to reach out if you’d like to test-drive or collaborate on AMASS for your airborne research needs.

Thank you for your continued support of our work at CloudSci! Stay tuned for upcoming test results and field deployment announcements—exciting times are ahead in atmospheric science.