About

Dr. Mike Gruntman's research focuses on astronautics, space science and technology, rocketry, spacecraft and space mission design, history of rocketry and spacecraft, and missile defense.

Research topics

• Engineering
• Physics
• Aerospace engineering
• Computational physics
• Computer Science
• Electrical engineering
• Astronomy
• Geology
• Environmental science
• Electronic engineering
• Optics
• Astrobiology

Selected publications

• Master of Science in Astronautical Engineering degree at the University of Southern California for the space industry

  Journal of Space Safety Engineering · 2024-08-14 · 2 citations

  article1st authorCorresponding
  PublisherDOI

• Pushing the Frontier of Solar & Space Physics: Exploration of the Heliosphere and the Very Local Interstellar Medium by an Interstellar Probe

  2023-07-31 · 1 citations

  articleOpen access

  Whitepaper #038 in the Decadal Survey for Solar and Space Physics (Heliophysics) 2024-2033. Main topics: basic research. Additional topics: outer heliosphere; space-based missions/projects; emerging opportunities.

  PublisherOA PDFDOI

• Interstellar probe – Destination: Universe!

  Acta Astronautica · 2022 · 43 citations

  • Computer Science
  • Astrobiology
  • Astronomy

  The idea of an “Outer solar system probe: to be aimed away from the Sun in the plane of the ecliptic” dates from a report of the “Simpson Committee” of the Space Science Board of the National Academy of Sciences in March of 1960. After many studies and name changes, what is now known as “Interstellar Probe” has matured as a concept for making new discoveries that can be made in no other way, by going places yet to be explored. The central technical question has always been propulsion with “near-future” capabilities taken as the backdrop for defining the mission requirements. However, the real issue has always been to unite compelling science with engineering and technical reality. With that perspective in mind the Johns Hopkins University Applied Physics Laboratory (APL) has been tasked by the NASA Heliophysics Division to (re-)study the mission and provide a Technical Report to be delivered late 2021 for input to next Solar and Space Physics Decadal Survey. This “pragmatic Interstellar Probe” of the study is a mission through the outer heliosphere and to the nearby “Very Local” interstellar medium (VLISM), uses today's technology to take the first explicit step on the path of interstellar exploration, and can pave the way, scientifically, technically, and programmatically for more ambitious future journeys (and more ambitious science goals). To enforce these goals broadly-based engineering requirements include (1) readiness to launch no later than January 1, 2030; (2) capability to transmit useful scientific data from 1000 au; (3) powered by no more than 600 W (electric) at the beginning of the mission and no more than half of that at mission's end; and, (4) lifetime of no less than 50 years. To travel as far and as fast as possible with available technology, the use of the Space Launch System Block 2 (SLS B2) cargo version is enabling: carrying the spacecraft as well as a 3rd and 4th stage, solar system escape speeds of at least twice that of Voyager 1 (i.e., up to 7.2 au/yr) should be possible. We provide a top-level summary of work accomplished to date, focusing on how the science goals drive and are affected by telecommunication options, guidance and control requirements, trajectory options, and the baseline system architecture and approach. “It isn't about where we are going. It's about the journey out there."

  DOI

• Parker Solar Probe FIELDS Instrument Charging in the Near Sun Environment: Part 1: Computational Model

  Journal of Geophysical Research Space Physics · 2021 · 11 citations

  Senior authorCorresponding
  • Physics
  • Aerospace engineering
  • Computational physics

  Abstract The Spacecraft Interaction Plasma Software package (SPIS), a three‐dimension particle in cell (PIC) code, was used to model the Parker Solar Probe (PSP) spacecraft and FIELDS instrument and their interactions with the Solar wind. Our SPIS modeling relied on material properties of new spacecraft materials that we had obtained in previous work. The model was used to find the floating potentials of the spacecraft and FIELDS antennas at different distances from the Sun (from 1AU to 0.046AU). We find the following results: At greater distances from the Sun, the shadowed spacecraft charges negatively while the illuminated Thermal Protection System (TPS) charges positive due to the high resistance of the TPS Alumina shield at low temperatures. As the spacecraft approaches the Sun, the temperature of the TPS increases, the resistance between it and the spacecraft drops, and its photoemission increases, driving the spacecraft more positive. At the same time, an electrostatic barrier forms near the illuminated surface of the TPS and reflects the photoelectrons back leading to negative charging of some surfaces. The FIELDS antennas and shield also see this barrier forming but on a smaller scale. The FIELDS antennas charge positively at all distances modeled when no current bias is applied. Current biasing of the antennas affects their floating potential.

  PublisherOA PDFDOI

• Parker Solar Probe FIELDS Instrument Charging in the Near Sun Environment: Part 2: Comparison of In‐Flight Data and Modeling Results

  Journal of Geophysical Research Space Physics · 2021 · 8 citations

  Senior authorCorresponding
  • Physics
  • Aerospace engineering
  • Computational physics

  Abstract This research shows Part II of the Spacecraft Interaction Plasma Software (SPIS) used to model the parker solar probe (PSP) FIELDS instrument and its interactions with the Solar Wind. Flight data were used to run the PSP model and compared with models using past predicted parameters. The effect of voltage biasing between the antenna, its shield, and the spacecraft on the current balance of each surface was investigated at first perihelion (0.16AU). The model data were reduced to I–V curves to find current saturations (analysis results 52 µA vs. flight results 54–72 µA), and sheath resistances (analysis results of 307 kΩ vs. flight results of 51 kΩ). The recommended bias current to ensure optimal sensitivity of the FIELDS antenna was between −52 and −22 µA, which corresponded to a differential potential with respect to the spacecraft between −5 and 5 V. The analysis also shows that plasma sheath of the FIELDS antenna and the plasma sheath of the FIELDS shield interacted between each other with an impedance of ∼220 kΩ.

  PublisherOA PDFDOI

• SIHLA , a Mission of Opportunity to L1 to Map H Lyman Alpha Emissions from the Heliopause, the Interplanetary Medium, the Earth's Geocorona and Comets

  2020-12-06 · 1 citations

  articleOpen access

  SIHLA (Spatial/Spectral Imaging of Heliospheric Lyman Alpha pronounced as ‘Scylla’ [e.g. Homer, Odyssey, ~675-725 BCE] investigates fundamental physical processes that determine the interaction of the Sun with the interstellar medium (ISM); the Sun with the Earth; and the Sun with comets and their subsequent evolution. To accomplish these goals, SIHLA studies the shape of the heliosphere and maps the solar wind in 3D; characterizes changes in Earth’s extended upper atmosphere (the hydrogen ‘geocorona’); discovers new comets and tracks the composition changes of new and known ones as they pass near the Sun. SIHLA is a NASA Mission of Opportunity that has just completed its Phase A study (the Concept Study Report or CSR). At the time of the writing of this abstract NASA has not decided whether to fly this small satellite mission or its competitor (GLIDE: PI Prof. Lara Waldrop). SIHLA observes the ion-neutral interactions of hydrogen, the universe’s most abundant element, from the edge of the solar system to the Earth, to understand the fundamental properties that shaped our own home planet Earth and the heliosphere. From its L1 vantage point, well outside the Earth’s obscuring geocoronal hydrogen cloud, SIHLA maps the entire sky using a flight-proven, compact, far ultraviolet (FUV) hyperspectral imager with a Hydrogen Absorption Cell (HAC). The hyperspectral scanning imaging spectrograph (SIS) in combination with the spacecraft roll, creates 4 maps >87% of the sky each day, at essentially monochromatic lines over the entire FUV band (115 to 180nm) at every point in the scan. During half of these daily sky maps, the hydrogen absorption cell (HAC) provides a 0.001nm notch rejection filter for the H Lyman a. Using the HAC, SIHLA builds up the lineshape profile of the H Lyman a emissions over the course of a year. SIHLA’s SIS/HAC combination enables us to image the result of the ion-neutral interactions in the heliosheath, 100 AU away, in the lowest energy, highest density, part of the neutral atom spectrum – H atoms with energies below 10eV. The novel aspects of SIHLA are the scope of the science done within a MoO budget. The SIHLA projected costs were below the $75M cap with a 31.3% reserve for Phase B-D. The re-purposing of a spectrographic that was part of the DMSP SSUSI line (a copy was flown and NASA TIMED/GUVI and as NASA NEAR/NIS). Risk is extremely low in this Class-D mission with all major elements at least at TRL6 at this time. SIHLA has a high potential for discovery. We expect that we will 1) First detection of the hot H atoms produced directly from the ion-neutral interactions at the heliopause; 2) First detection of structures in Interplanetary Medium H emission, 3) First detection of response of the Earth’s extended (out to lunar orbit) geocorona to solar/geomagnetic drivers, 4) New UV-bright comets as they enter the inner solar system. SIHLA is a hyperspectral imager; at every point in the sky SIHLA obtains the entire FUV spectrum.

  PublisherDOI

• Parker Solar Probe FIELDS instrument charging in the near Sun environment: Part I - Computational Model

  2020-09-19

  preprintOpen accessSenior author

  The Spacecraft Interaction Plasma Software package (SPIS), a three-dimension particle in cell (PIC) code, was used to model the Parker Solar Probe (PSP) spacecraft and FIELDS instrument and their interactions with the Solar wind. Our SPIS modeling relied on material properties of new spacecraft materials that we had obtained in previous work. The model was used to find the floating potentials of the spacecraft and FIELDS antennas at different distances from the Sun (from 1AU to 0.046AU). We find the following results: At greater distances from the Sun, the shadowed spacecraft charges negatively while the illuminated Thermal Protection System (TPS) charges positive due to the high resistance of the TPS Alumina shield at low temperatures. As the spacecraft approaches the Sun, the temperature of the TPS increases, the resistance between it and the spacecraft drops, and its photoemission increases, driving the spacecraft more positive. At the same time, an electrostatic barrier forms near the illuminated surface of the TPS and reflects the photoelectrons back leading to negative charging of some surfaces. The FIELDS antennas and shield also see this barrier forming but on a smaller scale. The FIELDS antennas charge positively at all distances modeled when no current bias is applied. Current biasing of the antennas affects their floating potential.

  PublisherDOI

• Progress Towards a Pragmatic Interstellar Probe

  AGU Fall Meeting Abstracts · 2020-12-01

  article
  Publisher

• Parker Solar Probe FIELDS instrument charging in the near Sun environment: Part II - Comparison of In-Flight Data and Modeling Results

  2020-09-19

  preprintOpen accessSenior author

  This research shows Part II of the Spacecraft Interaction Plasma Software (SPIS) used to model the Parker Solar Probe (PSP) FIELDS instrument and its interactions with the Solar Wind. Flight data was used to run the PSP model and compared with models using past predicted parameters. The effect of voltage biasing between the antenna, its shield, and the spacecraft on the current balance of each surface was investigated at first perihelion (0.16AU). The model data was reduced to I-V curves to find current saturations (analysis results 52µA versus flight results 54-72 µA), and sheath resistances (analysis results of 307 kΩ versus flight results of 51 kΩ). The recommended bias current to ensure optimal sensitivity of the FIELDS antenna was between -52 µA and -22 µA, which corresponded to a differential potential with respect to the spacecraft between -5V and 5V. The analysis also shows that plasma sheath of the FIELDS antenna and the plasma sheath of the FIELDS shield interacted between each other with an impedance of ~220kΩ.

  PublisherDOI

• Planning for a Pragmatic Interstellar Probe: Requirements, Desirements, Realities

  AGUFM · 2019-12-01

  article
  Publisher

Frequent coauthors

• H. O. Funsten

  New Mexico Consortium

  75 shared

• D. J. McComas

  Princeton University

  71 shared

• E. C. Roelof

  Johns Hopkins University Applied Physics Laboratory

  63 shared

• N. A. Schwadron

  University of New Hampshire

  53 shared

• S. M. Krimigis

  Johns Hopkins University Applied Physics Laboratory

  48 shared

• V. Izmodenov

  45 shared

• M. Bzowski

  Centrum Badań Kosmicznych

  42 shared

• F. Allegrini

  38 shared

Education

• Ph.D., Astronautical Engineering

  California Institute of Technology

  1986

• M.S., Astronautical Engineering

  California Institute of Technology

  1983

• B.S., Aeronautical Engineering

  Moscow Institute of Physics and Technology

  1979

Awards & honors

• 2020 Citation, Long Island Section, American Institute of Ae…
• 2020 Certificate of Appreciation, Los Angeles – Las Vegas Se…
• 2017 Distinguished Educator Award, Orange County Engineering…
• 2011 NASA Group Achievement Award
• 2006 International Academy of Astronautics Luigi Napolitano…