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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS2019

An Eccentric Massive Jupiter Orbiting a Subgiant on a 9.5-day Period Discovered in the Transiting Exoplanet Survey Satellite Full Frame Images

We report the discovery of TOI-172 b from the Transiting Exoplanet Survey Satellite (TESS) mission, a massive hot Jupiter transiting a slightly evolved G star with a 9.48-day orbital period. This is the first planet to be confirmed from analysis of only the TESS full frame images, because the host star was not chosen as a two-minute cadence target. From a global analysis of the TESS photometry and follow-up observations carried out by the TESS Follow-up Observing Program Working Group, TOI-172 (TIC 29857954) is a slightly evolved star with an effective temperature of T(eff) = 5645 ± 50 K, a mass of M(⋆) =1.128(sub -0.061, sup +0.065) M(☉), radius of R(⋆) =1.777(sub -0.044, sup +0.047) R(☉), a surface gravity of log g(⋆) =3.993(sub -0.028, sup +0.027), and an age of 7.4(sub -1.5, sup +1.6) Gyr. Its planetary companion (TOI-172 b) has a radius of R(P) =0.965(sub -0.029, sup +0.032) R(J), a mass of M(P) =5.42(sub -0.20, sup +0.22) M(J), and is on an eccentric orbit (e=0.3806(sub -0.0090, sup +0.0093)). TOI-172 b is one of the few known massive giant planets on a highly eccentric short-period orbit. Future study of the atmosphere of this planet and its system architecture offer opportunities to understand the formation and evolution of similar systems.

Joseph E. Rodriguez↗
NASA NTRS2010

Prospects for Habitable World Detections Using James Webb Space Telescope (JWST)

Doppler and transit surveys are finding extrasolar planets of ever smaller mass and radius, and are now sampling the domain of superEarths. Recent results from the Doppler surveys suggest that discovery of a transiting superEarth in the habitable zone of a lower main sequence star may be possible. We evaluate the prospects for an all-sky transit survey targeted to the brightest stars I that would find the most favorable cases for photometric and spectroscopic characterization using the James Webb Space Telescope. We use the proposed Transiting Exoplanet Survey Satellite (TESS) as representative of an all-sky survey. We couple the simulated TESS yield to a sensitivity model for the MIRI and NIRSpec instruments on JWST. Our sensitivity model includes all currently known and anticipated sources of random and systematic error for these instruments. We focus on the TESS planets with radii between Earth and Neptune. Our simulations consider secondary eclipse filter photometry using JWST/MIRI, comparing the 11- and 15- micron bands to measure carbon dioxide absorption in superEarths, as well as JWST!NIRSpec spectroscopy of water absorption from 1.7-3.0 microns, and carbon dioxide absorption at 4.3 microns. We find that JWST will be capable of characterizing dozens of TESS superEarths with temperatures above the habitable range, using both MIRI and NIRspec. We project that TESS will discover about eight nearby habitable transiting superEarths, all orbiting lower main sequence stars. The principal sources of uncertainty in the prospects for JWST characterization of habitable superEarths are superEarth frequency and the nature of superEarth atmospheres. Based on our estimates of these uncertainties, we project that JWST will be able to measure the temperature, and identify molecular absorptions (water, carbon dioxide) in one to four nearby habitable TESS superEarths orbiting lower main sequence stars.

Deming, Drake↗
NASA NTRS2020

TOI-481 b and TOI-892 b: Two Long-period Hot Jupiters from the Transiting Exoplanet Survey Satellite

We present the discovery of two new 10 day period giant planets from the Transiting Exoplanet Survey Satellite mission, whose masses were precisely determined using a wide diversity of ground-based facilities. TOI-481 b and TOI-892 b have similar radii (0.99 ± 0.01 R(J) and 1.07 ± 0.02 R(J), respectively), and orbital periods (10.3311 days and 10.6266 days, respectively), but significantly different masses (1.53 ± 0.03 M(J) versus 0.95 ± 0.07 M(J), respectively). Both planets orbit metal-rich stars ([Fe/HG] = +0.26 ± 0.05 dex and [Fe/H] = +0.24 ± 0.05 for TOI-481 and TOI-892, respectively) but at different evolutionary stages. TOI-481 is a M(*) = 1.14 ± 0.02 Mꙩ, R(*) = 1.66 ± 0.02 Rꙩ G-type star (T(eff) = 5735 ± 72 K), that with an age of 6.7 Gyr, is in the turn-off point of the main sequence. TOI-892 on the other hand, is a F-type dwarf star (T(eff) = 6261 ± 80 K), which has a mass of M(*) = 1.28 ± 0.03 Mꙩ and a radius of R(*) = 1.39 ± 0.02 Rꙩ. TOI-481 b and TOI-892 b join the scarcely populated region of transiting gas giants with orbital periods longer than 10 days, which is important to constrain theories of the formation and structure of hot Jupiters.

Rafael Brahm↗
NASA NTRS2015

Scientific, Back-Illuminated CCD Development for the Transiting Exoplanet Survey Satellite

We describe the development of the fully depleted, back illuminated charge coupled devices for the Transiting Exoplanet Survey Satellite, which includes a set of four wide angle telescopes, each having a 2x2 array of CCDs. The devices are fabricated on the newly upgraded 200-mm wafer line at Lincoln Laboratory. We discuss methods used to produce the devices and present early performance results from the 100- micron thick, 15x15-microns, 2k x 4k pixel frame transfer CCDs.

quantum efficiency↗
NASA NTRS1982

Transit telescope designs optimized for multiple object spectroscopy with fibers

Instruments to simultaneously study the spectra of many objects in the field of view of a telescope can be made using fused silica fibers. The spectrograph at the 2.3m telescope of the University of Arizona has been modified for such operation, and is used routinely to study the dynamics of galaxy clusters. Consideration has been given to how the multifiber technique can best be used to obtain spectra of the many faint objects identified by deep transit survey instruments and new space and radio telescopes. A transit survey such as that planned by McGraw et al. (1980), with CCDs at the focus of a 2m transit telescope, will identify objects down to 24th magnitude, and down to 22nd magnitude will give very complete data on variability and optical energy distribution. A telescope with much larger aperture is required for spectroscopic follow up. It is suggested that large telescopes dedicated to this type of work can be made and operated for only a fraction of the cost of a general-purpose telescope.

Angel, J. R. P.↗
NASA NTRSDate not supplied

Chasing Shadows in the Night: How NASA's Kepler and TESS Missions Are Revolutionizing Exoplanet Science

The first planet outside our own solar system was discovered almost thirty years ago in an extremely unlikely place, orbiting a pulsar, and the first exoplanet orbiting a Sun-like star was discovered nearly 26 years ago. In the time since, we’ve detected over 5000 planets and over 75% of these have been detected by transit surveys. The Kepler Mission, launched in 2009, has found the lion’s share of these exoplanets, and demonstrated that each star in the night sky has, on average, at least one planet. Kepler’s success spurred NASA and ESA to select several exoplanet-themed missions to move the field of exoplanet science forward from discovery to characterization: How do these planets form and evolve? What is the structure and composition of the atmospheres and interiors of these planets? Can we detect biomarkers in the atmospheres of these planets and learn the answer to the fundamental question, are we alone? NASA selected the Transiting Exoplanet Survey Satellite (TESS) in 2014 to conduct a nearly all-sky survey for transiting planets with the goal of identifying at least 50 small planets with measured masses that can be followed up by large telescopic assets, such as the upcoming James Webb Space Telescope. TESS has discovered 266 exoplanets so far, 100 of which are smaller than earth with measured masses. In this talk I will describe how we detect weak transit signatures in noisy but beautiful transit survey data sets and present some of the most compelling discoveries made so far by Kepler and TESS.

TESS↗
DOE OSTI2026

Onboard/Origin-Destination Survey - Phoenix - 2015

Valley Metro conducted an on-board transit survey during spring 2015. This project gathered updated travel behavior data from transit users that encompassed all rail and bus fixed-route services in the Phoenix metropolitan planning area. The study’s goal was to compile statistically accurate information about transit riders and how they use the transit system.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
NASA NTRS2015

Optical Design of the Camera for Transiting Exoplanet Survey Satellite (TESS)

The optical design of the wide field of view refractive camera, 34 degrees diagonal field, for the TESS payload is described. This fast f/1.4 cryogenic camera, operating at -75 C, has no vignetting for maximum light gathering within the size and weight constraints. Four of these cameras capture full frames of star images for photometric searches of planet crossings. The optical design evolution, from the initial Petzval design, took advantage of Forbes aspheres to develop a hybrid design form. This maximized the correction from the two aspherics resulting in a reduction of average spot size by sixty percent in the final design. An external long wavelength pass filter was replaced by an internal filter coating on a lens to save weight, and has been fabricated to meet the specifications. The stray light requirements were met by an extended lens hood baffle design, giving the necessary off-axis attenuation.

CCD↗
NASA NTRS2016

Thermal Design of the Instrument for the Transiting Exoplanet Survey Satellite

TESS observatory is a two year NASA Explorer mission which will use a set of four cameras to discover exoplanets. It will be placed in a high-earth orbit with a period of 13.7 days and will be unaffected by temperature disturbances caused by environmental heating from the Earth. The cameras use their stray-light baffles to passively cool the cameras and in turn the CCD's in order to maintain operational temperatures. The design has been well thought out and analyzed to maximize temperature stability. The analysis shows that the design keeps the cameras and their components within their temperature ranges which will help make it a successful mission. It will also meet its survival requirement of sustaining exposure to a five hour eclipse. Official validation and verification planning is underway and will be performed as the system is built up. It is slated for launch in 2017.

Thermal Engineering↗
DOE OSTI2026

Transportation Secure Data Center: Frequently Asked Questions for Data Owners/Contributors

The Transportation Secure Data Center is a centralized repository for detailed transportation data from travel and transit surveys and studies conducted across the nation. It makes vital transportation data broadly available to users while preserving the privacy of survey participants. Hundreds of datasets from surveys and studies of household travel and transit passenger travel are archived in the TSDC, including surveys and studies conducted by state departments of transportation, metropolitan planning organizations, transit agencies, cities, and other public agencies. Detailed data from travel surveys and studies are extremely valuable for research purposes. However, the fine-grained information they contain could potentially be misused to identify individual travelers, so access to these data should only be granted with safeguards in place to protect participant privacy. The TSDC was created to address this challenge and to relieve public agencies from the burden of archiving their data and responding to data requests.

33 ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2026

Transit Rider/Travel Behavior Inventory Survey - Minneapolis-St. Paul Metro - 2005

The survey was an on-board survey of transit riders on all regular route services for bus and light-rail in the Minneapolis-Saint Paul metropolitan area. The primary purpose of the study was to gather the data needed to update the mode choice models that are an integral component of the regional travel forecast model maintained by the Metropolitan Council, the metropolitan planning organization for the Minneapolis-Saint Paul metropolitan area. The survey instrument focused on identifying characteristics of the trip taken by each transit rider, including origin, destination, trip purpose, and mode of access. The survey also collected relevant socioeconomic and demographic information.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
NASA NTRS2017

Synergies Between the Kepler, K2 and TESS Missions with the PLATO Mission (Revised)

Two transit survey missions will have been flown by NASA prior to the launch of ESA's PLATO Mission in 2026, laying the groundwork for exoplanet discovery via the transit method. The Kepler Mission, which launched in 2009, collected data on its 100+ square degree field of view for four years before failure of a reaction wheel ended its primary mission. The results from Kepler include 2300+ confirmed or validated exoplanets, 2200+ planetary candidates, 2100+ eclipsing binaries. Kepler also revolutionized the field of asteroseismology by measuring the pressure mode oscillations of over 15000 solar-like stars spanning the lifecycle of such stars from hydrogen-burning dwarfs to helium-burning red giants. The re-purposed Kepler Mission, dubbed K2, continues to observe fields of view in and near the ecliptic plane for 80 days each, significantly broadening the scope of the astrophysical investigations as well as discovering an additional 156 exoplanets to date. The TESS mission will launch in 2017 to conduct an all-sky survey for small exoplanets orbiting stars 10X closer and 100X brighter than Kepler exoplanet host stars, allowing for far greater follow-up and characterization of their masses as well as their sizes for at least 50 small planets. Future assets such as James Webb Space Telescope, and ground-based assets such as ESOs Very Large Telescope (VLT) array, the Exremely Large Telescope (ELT), and the Thirty Meter Telescope (TMT) will be able to characterize the atmospheric composition and properties of these small planets. TESS will observe each 24 X 96 field of view for 30 days and thereby cover first the southern and then the northern hemisphere over 13 pointings during each year of the primary mission. The pole-most camera will observe the James Webb continuous viewing zone for one year in each hemisphere, permitting much longer period planets to be detected in this region. The PLATO mission will seek to detect habitable Earth-like planets with an instrument composed of 26 small telescopes in several 2232 square deg FOVs with a range of observation durations over a mission lifetime of up to eight years. This paper summarizes the findings of the KeplerK2 missions, previews the likely results from the TESS mission, and explores the lessons learned and to be learned from these prior missions that can be incorporated into the observation and data reduction strategy for the PLATO Mission so as to maximize the science return.

exoplanet detection↗
DOE OSTI2026

TSDC: Transportation Secure Data Center: Real-World Data for Planning, Modeling, and Analysis

The Transportation Secure Data Center is a centralized repository for high-resolution transportation data from hundreds of travel and transit surveys and studies. It makes vital transportation data broadly available to users while preserving the privacy of survey participants. It houses surveys and studies conducted by state departments of transportation, metropolitan planning organizations, transit agencies, cities, and other public agencies. Meanwhile, the Livewire Data Platform empowers research, industry, and academic partners to easily and securely preserve, maintain, share, discover, and gain access to transportation and mobility data. Livewire accommodates a range of datasets, including behavioral, experimental, model, analytical, and raw data at the vehicle, traveler, and system levels. Datasets support mobility research and planning spanning urban science, connected and automated vehicles, fueling and charging infrastructure, mobility decision science, multimodal transportation, vehicle efficiency, and more.

33 ADVANCED PROPULSION SYSTEMS↗