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The first successful flight demonstration of aerial deployment of Mars balloon prototypes in June 2002 and, earlier, of Venus balloon prototype deemed to be a turning point in the risk assessment of balloon missions.
NASA/Jet Propulsion Laboratory is designing a return mission to the Venusian atmosphere using a reversible fluid altitude control balloon called Balloon Experiment at Venus (BEV). This is a proposed NASA flight experiment to demonstrate key technologies for operation of advanced balloons in the atmosphere of Venus. This paper includes both the mission profile and system description of the proposed BEV concept.
Modeling and simulation of balloons and aerobots (robotic balloons) is an essential part of scientific balloon mission development and planning.
At the end of 1997, JPL initiated the Mars Balloon Validation Program (MABVAP) to develop and validate the technology needed for a Mars balloon mission. The main focus of MABVAP was to develop and to test a viable concept for the Martian balloon that could be implemented on the small-scale dedicated or piggy-back mission.
Solar Montgolfiere balloons, or solar-heated hot air balloons have been evaluated by use on Mars for about 5 years. In the past, JPL has developed thermal models that have been confirmed, as well as developed altitude control systems to allow the balloons to float over the landscape or carry ground sampling instrumentation. Pioneer Astronautics has developed and tested a landing system for Montgolfieres. JPL, together with GSSL. have successfully deployed small Montgolfieres (<15-m diameter) in the earth's stratosphere, where conditions are similar to a Mars deployment. Two larger Montgolfieres failed, however, and a series of larger scale Montgolfieres is now planned using stronger, more uniform polyethylene bilaminate, combined with stress-reducing ripstitch and reduced parachute deceleration velocities. This program, which is presently under way, is a joint effort between JPL, WFF, and GSSL, and is planned for completion in three years.
The goal of the Solid State Inflation Balloon Active Deorbiter project is to develop and demonstrate a scalable, simple, reliable, and low-cost active deorbiting system capable of controlling the downrange point of impact for the full-range of small satellites from 1 kg to 180 kg. The key enabling technology being developed is the Solid State Gas Generator (SSGG) chip, generating pure nitrogen gas from sodium azide (NaN3) micro-crystals. Coupled with a metalized nonelastic drag balloon, the complete Solid State Inflation Balloon (SSIB) system is capable of repeated inflation/deflation cycles. The SSGG minimizes size, weight, electrical power, and cost when compared to the current state of the art.
Project Loon has an overall goal of providing worldwide internet coverage using a network of long-duration super-pressure balloons. Beginning in 2013, Loon has launched over 1600 balloons from multiple tropical and middle latitude locations. These GPS tracked balloon trajectories provide lower stratospheric wind information over the oceans and remote land areas where traditional radiosonde soundings are sparse, thus providing unique coverage of lower stratospheric winds. To fully investigate these Loon winds we: 1) compare the Loon winds to winds produced by a global data assimilation system (DAS: NASA GEOS) and 2) assimilate the Loon winds into the same comprehensive DAS. Results show that in middle latitudes the Loon winds and DAS winds agree well and assimilating the Loon winds have only a small impact on short-term forecasting of the Loon winds, however, in the tropics the loon winds and DAS winds often disagree substantially (8 m/s or more in magnitude) and in these cases assimilating the loon winds significantly improves the forecast of the loon winds. By highlighting cases where the Loon and DAS winds differ, these results can lead to improved understanding of stratospheric winds, especially in the tropics.
The Columbia Scientific Balloon Facility (CSBF) has been designing and building high-altitude balloon power systems for over 28 years. With that experience, we have found certain types of PV panels, batteries, and charge controllers that are reliable in stratospheric environments. The goal is to ensure that power systems provide power reliably throughout the duration of an Long Duration Ballooning (LDB) flight. The purpose of this presentation is to provide some general guidelines and best practices for power system design.
Ballooning mode saturation is investigated in realistic stellarator configurations using the flux tube approach of Ham et al (2018 Plasma Phys. Control. Fusion 60 075017), Ham et al (2016 Phys. Rev. Lett. 116 235001). The method is adapted to account for the lack of exact force balance in stellarator equilibrium solvers that assume existence of nested flux surfaces. A variational approach for calculating flux tube energy is developed to overcome this force error problem in stellarator numerical equilibria. Saturated (equilibrium) flux tube states that cross 10%–20% of the plasma minor radius are shown to exist for linearly ballooning unstable profiles. It is shown that several features of the displaced flux tube structure in a full nonlinear MHD simulation of Wendelstein 7X are reproduced by our model. Saturated states are found in a compact stellarator equilibrium close but below the marginal ballooning linear instability, i.e. the unperturbed equilibrium is metastable. This suggests that edge-localized-mode-like explosive MHD behavior may be possible in stellarators.
Aerodynamic stability of balloons used for measuring the intensity and direction of atmospheric winds at various elevations is improved by incorporating a rough surface on the balloons. The rough-surfaced balloon is useful for collecting wind profiles and other meteorological data.
The error in the magnitude of the horizontal wind field as computed for balloons with linear and quadratic rise rates ascending through a light, moderate, or severe wind field is derived. The rise rate function of the Jimsphere is analyzed as a special case. Figures are presented of wind error versus altitude for each rise rate and wind field, assuming linear smoothing. The ultimate capability of rising balloon systems for measuring wind from the surface to 18 kilometers can be determined from the data and the wind accuracy can be computed by knowing only the rise rate behavior versus altitude. The radii of smooth and roughened spheres needed to achieve the desired rise rate at various altitudes are derived. The radii for smooth and roughened balloons for tow-meter-per-second to 20-meter-per-second rise rates at 10 and 14 km altitudes, and the wind-following capability for each are tabulated.
Experimental and analytical techniques for determining stability parameters for a balloon tethered in a steady wind are described. These techniques are applied to a particular 7.64-meter-long balloon, and the results are presented. The stability parameters of interest appear as coefficients in linearized stability equations and are derived from the various forces and moments acting on the balloon. In several cases the results from the experimental and analytical techniques are compared and suggestions are given as to which techniques are the most practical means of determining values for the stability parameters.
The thermal design and performance of the test vehicles used for the flight-qualification of the Viking parachute system are described. The desired range of test conditions was provided by a subsonic drop from a balloon altitude of 90,000 feet, and rocket-powered transonic and supersonic flights initiated at balloon altitudes of 120,000 feet. Unusual aspects of the thermal design approach included the application of techniques developed in support of planetary programs to the thermal analysis of balloon payloads and the use of ground firing data to establish realistic upper bounds for radiant plume heating during flight. The adequacy of thermal design is verified by flight data.
A 40 centimeter diameter aperture, balloon-borne telescope and ultraviolet spectrometer is described and selected scientific results are briefly reviewed. The general configuration of the 0.4 angstrom resolution instrument is shown and the utilization of servo-controlled secondary mirror, image dissector detector, and special mirror coatings are discussed. An outlook for astronomical research in the mid-ultraviolet from balloon-borne telescopes is presented together with future development plans for JSC's balloon-borne payload.
A configuration has been developed for a long-life balloon platform to carry pointing telescopes weighing as much as 80 pounds (36 kg) to point at selected celestial targets. A platform of this configuration weighs about 375 pounds (170 kg) gross and can be suspended from a high altitude super pressure balloon for a lifetime of several months. The balloon platform contains a solar array and storage batteries for electrical power, up and down link communications equipment, and navigational and attitude control systems for orienting the scientific instrument. A biaxial controller maintains the telescope attitude in response to look-angle data stored in an on-board computer memory which is updated periodically by ground command. Gimbal angles are computed by using location data derived by an on-board navigational receiver.
Localized sources of far infrared radiation (approximately 50 microns) have been detected during a high altitude balloon flight with a 40 cm telescope and silicon detectors. The flight system is described and preliminary results are presented. A large area of the sky has been scanned for localized sources of far infrared radiation, using a balloon-borne system that was sensitive to wavelengths beyond about 55 microns. Two Molectron silicon bolometers were used, with a Newtonian telescope having a 40 cm primary. The telescope was driven in azimuth at a fixed elevation; this mode of scanning was carried out for the duration of each of two balloon flights. The flight system is described.
A high sensitivity X-ray telescope system suitable for photometric type observations from balloon altitudes is described. The balloon gondola system is defined to include the performance requirements and the overall performance requirements of the balloon gondola support system. Diagrams of the gondola and the installed components are provided. The pointing and control system of the telescope is analyzed.
A balloon experiment which was used to determine the chemical composition of very high-energy cosmic rays up to and beyond 100 GeV/nucleon is described. The detector had a geometric factor of 1 sq m sr and a total weight on the balloon of 2100 kg. The apparatus consisted of an ionization spectrometer, spark chambers, and plastic scintillation and Cherenkov counters. It was calibrated at CERN up to 24 GeV/c protons and at DESY up to 7 GeV/c electrons. In October 1972 it was flown successfully on a stratospheric balloon.