Scanning electron image of monospecies biofilm isolated from the space 

station. The image was colored to visualize the bacterial cells (orange) 

embedded in the biofilm matrix (blue). The ESA-Biofilms investigation 

studies bacterial biofilm formation and antimicrobial properties of different 

metal surfaces under microgravity. NASA ID: jsc2023e010175
Publication Highlights

Earth and Space Science

The position of the space station in low Earth orbit provides a unique vantage point for collecting Earth and 

space science data. From an average altitude of about 400 kilometers, details in such features as glaciers, 

agricultural fields, cities, and coral reefs in images taken from the space station can be combined with data 

from orbiting satellites and other sources to compile the most comprehensive information available. Even 

with the many satellites now orbiting in space, the space station continues to provide unique views of our 

planet and the Universe. From the beginning of station to date, more than 900 articles have been published in 

the area of Earth and Space Science. 

The Roscomos-ASI-ESA

investigation Multiwavelength 

Imaging New Instrument for 

the Extreme Universe Space 

Observatory (Mini-EUSO) is 

a state-of-the-art multipurpose 

telescope designed to 

examine terrestrial, atmospheric, and cosmic 

ultraviolet emissions raining down on Earth. Its 

optical system of 36 multianode photomultiplier 

tubes capable of detecting single photons allow 

exceptional imaging during day/night and night/

day transitions (Figure 10). Mini-EUSO is the 

first mission of a larger program (JEM-EUSO) 

with about 300 scientists from 16 countries. 

In FY-23, five publications described the 

advanced technology of the telescope. In one 

of the publications, released in the Journal 

of Physics: Conference Series, researchers 

demonstrated the proper functionality of MiniEUSO, with regular collection of ultraviolet 

emissions data since 2019. 

Figure 10. Mini-EUSO mock-up displaying three main compartments (optics, focal 

surface, and data acquisition). Image adopted from Marcelli, Journal of Physics: 

Conference Series. 

Air showers, a cascade of ionized particles and 

electromagnetic radiation that produce a streak 

of fluorescent light when ultrahigh-energy 

cosmic rays enter the Earth’s atmosphere, 

have been studied by ground telescopes 

located in the Northern and Southern 

hemispheres. Observing the fluorescent light 

from space with a telescope such as MiniEUSO allows researchers to determine the 

energy of the cosmic rays, the arrival direction, 

and the position of the shower. 

The high spatial and temporal resolution of 

Mini-EUSO provides the capability to study 

Transient Luminous Events (TLEs), Emission 

of Light and Very Low Frequency perturbations 

due to Electromagnetic Pulse Sources 

(ELVES), meteors, strange quark matter, space 

debris, marine phytoplankton bioluminescence, 

marine pollution, geomagnetic disturbances, 

ultra-high energy cosmic rays, and climate 

effects. 

The ESA investigation 

Atmosphere-Space 

Interactions Monitor 

(ASIM), which has been 

installed externally on the 

station’s Columbus module 

since early 2018, monitors 

thunderstorm activity and its impact on the 

Earth’s atmosphere and climate. From the 

top of station without cloud obstacles, ASIM 

can better detect different types of transient 

luminous events such as blue jets, red sprites, 

green ghosts, halos, and ELVES to provide indepth data of these high energy emissions. 

Marcelli L, Battisti M, Belov A, Bertaina M, Cambiè G, et al. The Mini-EUSO telescope on board the ISS: in-flight operations and 

performances. Journal of Physics: Conference Series. 2022 November; 2374 (1): 012048. DOI: 10.1088/1742-6596/2374/1/012048 

15 
Publication Highlights

Earth and Space Science

Figure 11. Diagram showing the stages of in-cloud lightening development. Image adopted from Huang Geophysical Research 

Letters. 

This advanced technology provides weather 

information to alert communities, martime 

vessels, and aircraft in the path of dangerous 

storms. A NASA ScienceCast video

further demonstrated all the benefits of this 

investigation. 

In a new study published in the journal of 

Geophysical Research Letters, researchers 

combined radio signals and optical imaging 

to study the transition of 30 in-cloud flashes 

in detail. Researchers identified lightning 

changes that transitioned from upward leaders 

(i.e., positively charged “cold” lightning initiated 

and rising from a tall building, tower, or wind 

turbine) to scattered horizontal emissions 

across the clouds (Figure11). From space, 

this phenomenon was observed as blue 

radiance that rapidly dissipated at the onset 

of the transition compared to red radiance 

that remained virtually unchanged. An 

observation of reduced blue/red optical ratio 

coinciding with initial breakdown pulses (i.e., 

early electromagnetic field pulses emitted by 

lightning), led researchers to suggest that 

changes in the electromagnetic field form 

large currents of leader channels. Therefore, 

lightning transitions may begin when the 

electric charge in the 

main leader channel 

has reached its 

maximum. 

Additional 

cloud-to-ground 

measurements 

reported similar 

transitions from 

upward and 

stepped leaders 

(i.e., lightning 

that develops 

downward in quick 

steps), suggesting 

a connection. 

Researchers 

hypothesize that upward and stepped leaders 

have different physical properties. 

The NASA investigation 

Neutron star Interior 

Composition Explorer 

(NICER) analyzes neutron 

stars, bright star residues that 

remain after the explosion of 

massive stars, providing new 

insights into their nature and behavior. NICER 

also includes the Station Explorer for X-ray 

Timing and Navigation Technology (SEXTANT) 

to demonstrate a GPS-like capability by 

detecting bright millisecond pulses in the 

cosmos (i.e., pulsars) to enable autonomous 

navigation throughout the solar system and 

beyond. 

In a new study published in The Astrophysical 

Journal, researchers updated mathematical 

models of timing accuracy to investigate the 

rotational period of six pulsars. This study was 

a significant undertaking from an international 

collaboration of six countries (Chile, the 

Netherlands, France, Germany, Poland, Japan, 

and the US). The accurate measurement of 

Huang A, Cummer S, Pu Y, Chanrion O, Neubert T, et al. Transition in optical and radio features during the early development of negative 

intracloud leader. Geophysical Research Letters. 2022 November 28; 49(22): e2022GL100594. DOI: 10.1029/2022GL100594. 

16
Publication Highlights

Earth and Space Science

pulsars’ rotational period allows researchers 

to infer their properties and prompt their 

classification. Additionally, precise timing 

calculations allow researchers to examine 

the potential effects of pulsar rotation on 

gravitational waves. 

Figure 12. Two rotation cycles for one of the five pulsars examined by NICER 

and NuSTAR. Data from multiple space instruments allowed researchers to adjust 

previous calculations to better understand the spinning of neutron starts. Image 

adopted from Ho, The Astrophysical Journal. 

Through calculations of multiple data obtained 

from NICER, Chandra, and NuSTAR, 

researchers reported new, corrected rotation 

numbers for two pulsars by considering 

when the actual pulse occurred and the time 

of arrival of the pulse to Earth (Figure 12). 

Additionally, the timing baselines of three 

pulsars were extended three to four times over 

previous calculations. For a young energetic 

pulsar, researchers detected 15 glitches over 

4.5 years of data collection. These glitches in 

pulsar monitoring denote timing irregularities 

that may result from detached superfluid 

vortices. 

These advances in precise measurement 

enhances the understanding of pulsar 

properties and their effects on our solar system 

and planet. 

The JAXA investigation 

CALorimetric Electron 

Telescope (CALET) is 

a high-resolution particle 

detector able to distinguish 

different types of particles 

from cosmic rays and 

dark matter. It includes an imaging and a 

total absorption calorimeter to measure 

energy loss and to observe the paths of highenergy cosmic ray nuclei. The hardware was 

launched to station in 2015 and installed on 

the Japanese Experiment Module Exposure 

Facility. Analysis of CALET data provides 

new insight into the source of cosmic rays, 

the nature of energy particle acceleration 

mechanisms, and the characteristics of 

interstellar space in our galaxy. 

In a new study published in Physical Review 

Letters, through an extensive collaboration 

between Japan, Italy, and the United States, 

researchers examined helium particles from 

a large energy interval (~40 Giga-electronvolts to ~250 Tera-electron-volts) collected 

from 2015 to 2022. CALET measurements 

demonstrated that the helium spectrum 

fluctuates from lower to higher energy, and its 

Ho WC, Kuiper LM, Espinoza CM, Guillot S, Ray PS, et al. Timing six energetic rotation-powered X-ray pulsars, including the fast-spinning 

young PSR J0058-7218 and Big Glitcher PSR J0537-6910. The Astrophysical Journal. 2022 November 1; 939(1): 7pp. DOI: 10.3847/1538-

4357/ac8743. 

17 
Publication Highlights

Earth and Space Science

most significant deviation 

shows energy increases 

(Figure 13). These 

measurements agree with 

other space instruments 

such as PAMELA, AMS-02, 

DAMPE, and CREAM. 

Unexpectedly, researchers 

found that at lower 

energies (slow-moving 

particles), there was 

a “hardening” of the 

spectrum – more helium 

nuclei than expected were 

found, whereas at higher 

energies (fast-moving 

particles), less helium was 

found. The presence of 

these “features” (increase and decrease of the 

particle flux depending on the energy) allowed 

researchers to assess which statistical model 

best explained these trends. 

This study allows researchers to understand 

how cosmic rays travel and propagate through 

the galaxy, providing additional discrimination 

between the theoretical models proposed 

to explain their behavior and improve our 

understanding of cosmic ray origins. 

Figure 13. Cosmic ray helium spectrum as measured by multiple space instruments. Image adopted from Adriani, Physical 

Review Letters. 

Adriani O, Akaike Y, Asano K, Asaoka Y, Berti E, et al. Direct measurement of the cosmic-ray helium spectrum from 40 GeV to 250 TeV 

with the Calorimetric Electron Telescope on the International Space Station. Physical Review Letters. 2023 April 27; 130(17): 171002. DOI: 

10.1103/PhysRevLett.130.171002. 

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