Nozair Khawaja

• PhD
• PostDoc Position at Freie Universität Berlin

The Surface Dust Analyser (SUDA) is a mass spectrometer onboard the Europa Clipper mission for investigating the surface composition of the Galilean moon Europa. Atmosphereless planetary moons such as the Galilean satellites are wrapped into a ballistic dust exosphere populated by tiny samples from the moon’s surface produced by impacts of fast mic...

Results from the Cassini mission at Enceladus revealed the presence of a diverse organic inventory [1,2] in its subsurface ocean as well as ongoing hydrothermal activity at the water-rock interface [3,4]. Ice grains ejected into the plume are thought to contain compounds originating from the depths of the ocean, which are likely linked to hydrother...

Icy bodies with subsurface oceans are a prime target for astrobiology investigations, with an increasing number of scientists participating in the planning, development, and realization of space missions to these worlds. Within Germany, the Ocean Worlds and Icy Moons working group of the German Astrobiology Society provides an invaluable platform f...

We analyzed data recorded by the Cosmic Dust Analyzer on board the Cassini spacecraft during Enceladus dust plume traversals. Our focus was on profiles of relative abundances of grains of different compositional types derived from mass spectra recorded with the Dust Analyzer subsystem during the Cassini flybys E5 and E17. The E5 profile, correspond...

The DESTINY⁺(Demonstration and Experiment of Space Technology for INterplanetary voYage with Phaethon fLyby and dUst Science) Dust Analyser (DDA) is a state-of-the-art dust telescope for the in situ analysis of cosmic dust particles. As the primary scientific payload of the DESTINY⁺ mission, it serves the purpose of characterizing the dust environm...

The Cassini mission provided evidence for a global subsurface ocean and ongoing hydrothermal activity on Enceladus, based on results from Cassini’s mass spectrometers. Laboratory simulations of hydrothermal conditions on icy moons are needed to further constrain the composition of ejected ice grains containing hydrothermally altered organic materia...

The selected ice nanoparticle accelerator, SELINA, was used to prepare beams of single ice particles with positive or negative charge. Positively charged particles were prepared from deionized water and 0.05–0.2 molar solutions of sodium chloride in water, and negatively charged ice particles were generated from water without salt. Depending on the...

We performed experiments of implantation of energetic sulfur ions (105 keV) into 2:1 water:propane ices at 80 K and analyzed the resulting refractory organic matter with ultrahigh-resolution mass spectrometry. Our goal was to characterize the organic matter processed in the surface conditions of Europa, where it would receive a heavy flux of energe...

Characterizing the geochemistry of Europa and Enceladus is a key step for astrobiology investigations looking for evidence of life in their subsurface oceans. Transition metals with several oxidation states, such as iron, may be tracers of the oxidation state of icy ocean moon interiors. Their detection, as well as the characterization of their oxi...

Icy moons like Enceladus, and perhaps Europa, emit material sourced from their subsurface oceans into space via plumes of ice grains and gas. Both moons are prime targets for astrobiology investigations. Cassini measurements revealed a large compositional diversity of emitted ice grains with only 1 to 4% of Enceladus’s plume ice grains containing o...

Before the end of its mission, the Cassini spacecraft orbited Saturn in a series of highly inclined elliptical ‘Ring-Grazing’ orbits (RGO). During the RGO, the spacecraft passed repeatedly through the ring plane outside the F ring, near the orbits of Janus and Epimetheus, at an average relative speed of ∼20 km s–1. For the first time, Cassini's Cos...

Saturn's large and diffuse E ring is populated by microscopic water ice dust particles, which originate from the Enceladus plume. Cassini’s Cosmic Dust Analyser (CDA) sampled these ice grains, revealing three compositional particle types with different concentrations of salts and organics. Here we present the analysis of CDA mass spectra from sever...

The concept of a biosignature is widely used in astrobiology to suggest a link between some observation and a biological cause, given some context. The term itself has been defined and used in several ways in different parts of the scientific community involved in the search for past or present life on Earth and beyond. With the ongoing acceleratio...

The surface ice of Europa is known to contain high proportions of inorganic material that could heavily influence the compositional analysis of organic compounds in ejecta ice grains by the SUrface Dust Analyzer (SUDA) impact ionization mass spectrometer onboard NASA’s Europa Clipper mission. We previously have analyzed the effects of NaCl on the m...

We discuss the synergies between heliospheric and dust science, the open science questions, the technological endeavors and programmatic aspects that are important to maintain or develop in the decade to come. In particular, we illustrate how we can use interstellar dust in the solar system as a tracer for the (dynamic) heliosphere properties, and...

We discuss the synergies between heliospheric and dust science, the open science questions, the technological endeavors and programmatic aspects that are important to maintain or develop in the decade to come. In particular, we illustrate how we can use interstellar dust in the solar system as a tracer for the (dynamic) heliosphere properties, and...

Saturn’s moon Enceladus harbours a global ¹ ice-covered water ocean 2,3 . The Cassini spacecraft investigated the composition of the ocean by analysis of material ejected into space by the moon’s cryovolcanic plume 4–9 . The analysis of salt-rich ice grains by Cassini’s Cosmic Dust Analyzer ¹⁰ enabled inference of major solutes in the ocean water (...

Results from the Cassini‐Huygens space mission at Enceladus revealed a substantial inventory of organic species embedded in plume and E ring ice grains originating from a global subsurface and putative habitable ocean. Compositional analysis by the Cosmic Dust Analyzer indicated the presence of aromatic species and constrained some structural featu...

Europa and Enceladus, respective moons of Jupiter and Saturn, are prime targets in the exploration of potentially habitable extraterrestrial ocean worlds. Organic material could be incorporated from the ocean into ice grains ejected from the surface or in potential plumes and detected via spacecraft flybys with impact ionization mass spectrometers,...

The reliable identification of biosignatures is key to the search for life elsewhere. On ocean worlds like Enceladus or Europa, this can be achieved by impact ionization mass spectrometers, such as the SUrface Dust Analyzer (SUDA) on board NASA's upcoming Europa Clipper mission. During spacecraft flybys, these instruments can sample ice grains form...

Mass spectrometers on board spacecraft typically use either impact ionization or electron ionization (EI) as ion sources. Understanding the similarities and differences in the spectral signatures and fragmentation patterns produced by different techniques in mass spectrometry could elucidate the composition of organic compounds. Here we present a c...

Spaceborne impact ionization mass spectrometers, such as the Cosmic Dust Analyzer on board the past Cassini spacecraft or the SUrface Dust Analyzer being built for NASA's upcoming Europa Clipper mission, are of crucial importance for the exploration of icy moons in the Solar System, such as Saturn's moon Enceladus or Jupiter's moon Europa. For the...

The identification of biosignatures on extraterrestrial ocean worlds is key to the search for life on these bodies. Saturn’s icy moon Enceladus, and possibly Jupiter’s moon Europa, eject plumes containing gas and ice grains formed from subsurface salty water into space [1,2,3,4]. The emitted ice grains can be analyzed by impact ionization mass spec...

The plume of Enceladus is unique in the solar system in providing direct access to fresh material from an extraterrestrial subsurface ocean. The Cassini Mission, though not specifically designed for it, was able to take advantage of the plume to conduct the best characterization to date of an extraterrestrial ocean. Evidence gathered from multiple...

Here we highlight recent advances in our knowledge about Saturn’s ring system and bring forward the outstanding science issuesthat could be addressed by studying the ring systems of the ice giants. We focus on interactions between planetary rings and other elements in the system, including the moons, host planet, and its magnetosphere, and conclude...

Identifying and distinguishing between abiotic and biotic signatures of organic molecules such as amino acids and fatty acids is key to the search for life on extraterrestrial ocean worlds. Impact ionization mass spectrometers can potentially achieve this by sampling water ice grains formed from ocean water and ejected by moons such as Enceladus an...

Research on the origin of life is highly heterogeneous. After a peculiar historical development, it still includes strongly opposed views which potentially hinder progress. In the 1st Interdisciplinary Origin of Life Meeting, early-career researchers gathered to explore the commonalities between theories and approaches, critical divergence points,...

Reliable identification of biosignatures, such as amino acids, fatty acids, and peptides, on extraterrestrial ocean worlds is a key prerequisite for space missions that search for life or its emergence on these worlds. One promising approach is the use of high-performance in situ impact ionization mass spectrometers to sample water ice grains emerg...

Saturn’s moon Enceladus is erupting a plume of gas and ice grains from its south pole. Linked directly to the moon’s subsurface global ocean, plume material travels through cracks in the icy crust and is ejected into space. The subsurface ocean is believed to be in contact with the rocky core, with ongoing hydrothermal activity present. The Cassini...

Rationale: Detecting ice grains with impact ionization mass spectrometers in space provides information about the compositions of ice grains and their sources. Depending on the impact speeds of the ice grains onto the metal target of a mass spectrometer, ionization conditions can vary substantially, resulting in changes to the appearance of the re...

Cassini's last look at Saturn's rings During the final stages of the Cassini mission, the spacecraft flew between the planet and its rings, providing a new view on this spectacular system (see the Perspective by Ida). Setting the scene, Spilker reviews the numerous discoveries made using Cassini during the 13 years it spent orbiting Saturn. Iess et...

Cassini's final phase of exploration The Cassini spacecraft spent 13 years orbiting Saturn; as it ran low on fuel, the trajectory was changed to sample regions it had not yet visited. A series of orbits close to the rings was followed by a Grand Finale orbit, which took the spacecraft through the gap between Saturn and its rings before the spacecra...

Saturn's moon Enceladus harbours a global water ocean 1 , which lies under an ice crust and above a rocky core 2 . Through warm cracks in the crust 3 a cryo-volcanic plume ejects ice grains and vapour into space4-7 that contain materials originating from the ocean8,9. Hydrothermal activity is suspected to occur deep inside the porous core10-12, pow...

The general topic of this dissertation is the analysis of impact ionization time-of-flight mass spectra of ice grains in Saturn’s E ring sampled in-situ by the Cosmic Dust Analyzer (CDA) onboard the Cassini-Huygens spacecraft. The source of these E ring ice grains is the subsurface ocean of Saturn’s cryo-volcanically active icy moon Enceladus. The...

Cassini detects interstellar dust grains The interstellar medium contains an array of small solid particles known as dust grains. Altobelli et al. used the dust analyzer on the Cassini probe to detect 36 interstellar dust grains as they passed by Saturn, and they measured the grains' elemental abundances. The results show that, remarkably, these gr...

Pure water ice dominates the composition of the micron and sub-micron sized dust particles in Saturn’s E-ring, a ring constantly replenished by active ice jets of the moon Enceladus [1]. Details about the composition of this tenuous, optically thin ring can only be constrained by in situ measurements. The Cosmic Dust Analyzer (CDA) onboard Cassini...

Cassini’s Cosmic Dust Analyzer (CDA) generates time-of-flight mass spectra of individual grains impinging on the instruments target-plate. Following the analysis of salt rich ice grains emitted by Enceladus that indicated a salt-water ocean in contact with the moon’s rocky core [1,2] a recent CDA analysis of nano-phase silica particles pointed at h...

The Cosmic Dust Analyzer (CDA) aboard the Cassini spacecraft performs in-situ measurements of the chemical composition of icy dust grains impinging onto the target surface. The instrument recorded cationic Time-of-Flight (ToF) mass spectra of organic-bearing ice grains emitted from Enceladus at different impact velocities causing different molecula...

The ice and dust particles ejected into Saturn's E-ring provide direct insight into the composition of Enceladus' sub-surface ocean. This ocean is in contact with the rocky-core and there is evidence for hydrothermal activity [1][2]. Chemical species in the liquid are transported through vents and ejected out of Enceladus in the form of gas and ice...

ENIJA was developed to search for the prebiotic molecules and biogenic key compounds like amino acids in the plumes of Saturn's moon Ence-ladus. ENIJA records time-of-flight mass spectra in the range between 1 and 2000 u produced by high-velocity impacts of individual grains onto a metal target. The spectrometer has a measurement mode for cations o...

The major source of ice particles in Saturn's E-ring is Enceladus – a geological active moon of Saturn. Enceladus is emanating ice particles from its fractured south polar terrain (SPT), the so-called " Tiger Stripes ". The source of Enceladus activity and many of the ice particles is a subsurface ocean. The Cosmic Dust Analyzer (CDA) onboard the C...

ENIJA was developed to search for the prebiotic molecules and biogenic key compounds like amino acids in the plumes of Saturn's moon Enceladus. ENIJA records time-of-flight mass spectra in the range between 1 and 2000 u produced by high-velocity impacts of individual grains onto a metal target. The spectrometer has a measurement mode for cations or...

The Cassini spacecraft was launched in 2004 towards the Saturnian system to address major scientific questions about the planet, its magnetosphere, rings and icy moons. We have performed compositional mapping of Saturn's E-ring during the Cassini's flyby (R4) of Rhea, the second largest moon of Saturn, on 9th March 2013. The icy or rocky dust parti...

The Cosmic Dust Analyser (CDA) on board the Cassini spacecraft sampled Enceladus' plume ice particles emanated directly from Enceladus' fractured south polar terrain (SPT), the so-called "Tiger Stripes", during two consecutive flybys (E17 and E18) in 2012. The spacecraft passed through the dense plume with a moderate velocity of ~ 7.5km/s, horizont...

COSIMA Project: Overview COSIMA Instrument COSIMA Specification Comets are considered as the least processed leftover of the solar nebula. Exploring comets can unlock the mysterious nature and the origin of the cometary material. Ground based observations reveal limited information about the detailed composition of comets. The Rosetta space mission...