A5034263836- Adaptive optics and wavefront sensing
- Stellar, planetary, and galactic studies
- Remote Sensing and LiDAR Applications
- Astronomy and Astrophysical Research
- Planetary Science and Exploration
- Astro and Planetary Science
- Spacecraft Design and Technology
- Forest ecology and management
- Ionosphere and magnetosphere dynamics
- Remote Sensing in Agriculture
- Atmospheric Ozone and Climate
- Forest Ecology and Biodiversity Studies
- Spacecraft and Cryogenic Technologies
- Calibration and Measurement Techniques
- Solar and Space Plasma Dynamics
- Advanced Optical Sensing Technologies
- Optical Systems and Laser Technology
- Space Satellite Systems and Control
- Plant Water Relations and Carbon Dynamics
- CCD and CMOS Imaging Sensors
- Surface Roughness and Optical Measurements
- Astrophysics and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Geophysics and Gravity Measurements
- Advanced Measurement and Metrology Techniques
University of Massachusetts Lowell
2014-2023
Boston University
2012
The dual-wavelength Echidna lidar is a portable ground-based full-waveform terrestrial scanning for characterization of fine-scale forest structure and biomass content. While scanning, the instrument records full time series returns at half-nanosecond rate from two coaligned 5-ns pulsed lasers 1064 1548 nm wavelengths. Leaves absorb more strongly compared to stems, allowing discrimination composition milliradian scales ground canopy. This work describes design data products demonstrates...
The Dual-Wavelength Echidna® Lidar (DWEL), a ground-based, full-waveform lidar scanner designed for automated retrieval of forest structure, uses simultaneously-pulsing, 1064 nm and 1548 lasers to separate scattering by leaves from trunks, branches, ground materials. Leaf hits are separated others reduced response at due water absorption leaf cellular contents. By digitizing the full return-pulse waveform (full-width half maximum, 1.5 m) 7.5 cm intervals, can identify type event, as well...
The PICTURE-B sounding rocket mission is designed to directly image the exozodiacal light and debris disk around Sun-like star Epsilon Eridani. payload used a 0.5[Formula: see text]m diameter silicon carbide primary mirror visible nulling coronagraph which, in conjunction with fine pointing system capable of 5[Formula: text]milliarcsecond stability, was circumstellar environment nearby at small angles from high contrast. Besides contributing an important science result, matures essential...
An exoplanet mission based on a high-altitude balloon is next logical step in humanity's quest to explore Earthlike planets orbits orbiting Sunlike stars. The described here capable of spectrally imaging debris disks and exozodiacal light around number stars spanning range infrared excesses, stellar types, ages. designed characterize the background near those stars, study themselves, look for systems. scattered emitted from disk key uncertainty design any direct mission, thus, its...
Terrestrial laser scanning combining both near-infrared (NIR) and shortwave-infrared (SWIR) wavelengths can readily distinguish broad leaves from trunks, branches, ground surfaces. Merging data the 1548 nm SWIR in Dual-Wavelength Echidna <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">®</sup> Lidar (DWEL) instrument engineering trials with 1064 NIR Validation Instrument (EVI), we imaged a deciduous forest scene at Harvard Forest, Petersham,...
We describe the capabilities and performance of a terrestrial laser scanning instrument built for purpose recording retrieving three-dimensional structure forest vegetation. The dual-wavelength Echidna® lidar characterizes at an angular resolution as fine 1 mrad while distinguishing between leaves trunks by exploiting their differential reflectances two wavelengths: 1.5 μm. records full waveforms return signals from 5 ns pulses half-nanosecond time resolution; obtains ±117 deg zenith 360...
The Planetary Imaging Concept Testbed Using a Recoverable Experiment - Coronagraph (PICTURE-C) mission will directly image debris disks and exozodiacal dust around nearby stars from high-altitude balloon using vector vortex coronagraph. first flight of PICTURE-C was recently rescheduled by NASA for September, 2019. This paper describes preparations the PICTURE-C, including final design, integration process observation plan. Laboratory measurements low-order wavefront control system...
The PICTURE-C mission will fly a 60 cm off-axis unobscured telescope and two high-contrast coronagraphs in successive high-altitude balloon flights with the goal of directly imaging spectrally characterizing visible scattered light from exozodiacal dust interior 1-10 AU nearby exoplanetary systems.The first flight 2017 use 10 ´4 nulling coronagraph (previously flown on PICTURE sounding rocket) second 2019 ´7 vector vortex coronagraph.A low-order wavefront corrector (LOWC) be used both to...
We describe a high-throughput (5×10−4 cm2 sr) imaging spectrograph that uses an echelle grating operating at high dispersion order (24 to 43) observe extended sources such as atmospheric airglow and diffuse proton aurora spectral resolution (approximately 0.02 nm). Instead of using traditional single slit, the implementation instrument described here four (50 μm×25 mm) slits through which radiation enters spectrograph. The field view is selected appropriate foreoptics: present long, narrow...
The Planetary Imaging Concept Testbed Using a Recoverable Experiment - Coronagraph (PICTURE-C) mission will directly image debris disks and exozodiacal dust around nearby stars from high-altitude balloon using vector vortex coronagraph. Four leakage sources owing to the optical fabrication tolerances coatings are: electric field conjugation (EFC) residuals, beam walk on secondary tertiary mirrors, surface scattering, polarization aberration. Simulations analysis of these four for PICTUREC...
Abstract Energies and fluxes of precipitating electrons in an aurora over Lowell, MA on 22–23 June 2015 were derived based simultaneous, high‐resolution (≈ 0.02 nm) brightness measurements (427.8 nm, blue line), OI (557.7 green (630.0 red line) emissions. The electron energies energy as a function time look direction by nonlinear minimization model predictions with respect to the measurements. Three different methods compared; first two methods, we constrained modeled brightnesses ratios,...
The Planetary Imaging Concept Testbed Using a Recoverable Experiment - Coronagraph (PICTURE-C) mission is designed to directly image debris disks and exozodiacal dust around nearby stars from high-altitude balloon using 60 cm diameter off-axis telescope vector vortex coronagraph. During its second flight Fort Sumner, New Mexico, on September 28, 2022, PICTURE-C successfully used high low-order wavefront control systems perform focal plane correction for the first time an observatory in...
Primarily through indirect observational techniques, the existence of thousands exoplanetary systems has been confirmed. However, we still do not have an image system in reflected visible light. This is important because planetary as old solar (∼5 G yr) cooled to near equilibrium and are thus no longer bright being detected by current infrared coronagraphs. Furthermore, bandpass contains valuable information about aerosols, hazes, clouds that unavailable investigations. Our research group...
The Planetary Imaging Concept Testbed Using a Recoverable Experiment - Coronagraph (PICTURE-C) mission will directly image debris disks and exozodiacal dust around three nearby stars from high-altitude balloon using vector vortex coronagraph. We present experimental results of the PICTURE-C low-order wavefront control (LOWFC) system utilizing Shack-Hartmann (SH) sensor in an instrument testbed. SH drives both alignment telescope secondary mirror 6-axis Hexapod surface parallel array...
This study presents a three-dimensional (3-D) forest reconstruction methodology using the new and emerging science of terrestrial full-waveform lidar scanning, which can provide rapid efficient measurements canopy structure. A 3-D provides pathway to estimate structural parameters such as tree diameter at breast height, crown diameter, stem count density (trees per hectare). It enables detailed structure with respect (foliage or branch/trunk), well generation digital elevation model (DEM)...
The Planetary Imaging Concept Testbed Using a Recoverable Experiment - Coronagraph (PICTURE C) is high-altitude balloon-borne observatory that used vector vortex coronagraph to image dust and debris disks around nearby stars, as well develop test technology necessary for direct imaging of exoplanets from flight platform. balloon environment presents several challenges: an ambient pressure temperature approximately 4 Torr 220-240 K, combined with significant varying solar irradiance, lead...
The PICTURE-C balloon mission launched on its second flight from Fort Sumner, NM September 28, 2022. During this flight, PICTURE-C, which consists of a 60 cm off-axis telescope feeding vector vortex coronagraph, demonstrated the first high-contrast dark hole an observatory in near-space environment. coronagraph achieved modest broadband (20%) contrast ratio 5 x 10<sup>-6</sup> , with performance limited by dynamic pointing transients. low-order wavefront control system optical stabilization...
The Planetary Imaging Concept Testbed Using a Recoverable Experiment - Coronagraph (PICTURE-C) mission will directly image debris disks and exozodiacal dust around nearby stars from high-altitude balloon using vector vortex coronagraph. first flight of PICTURE-C launched the NASA Columbia Scientific Balloon Facility (CSBF) in Ft. Sumner, NM on September 28, 2019. This successfully demonstrated many key technologies for exoplanetary direct imaging missions all hardware components second,...
We describe a high etendue (0.12 cm(2) sr) camera that, without moving parts, simultaneously images four ultraviolet bands centered at 140, 175, 215, and 255 nm on single detector into minimum of ~7500 resolution elements. In addition to being an efficient way make color photometric measurements static scene, the described here enables detection spatial temporal information that can be used reveal energy dependent physical phenomena complement capability other instruments ranging in...