More Bucks for the Bang: New Space Solutions, Impact Tourism and one Unique Science & Engineering Opportunity at T-6 Months and Counting

For now, the Planetary Defense Conference Exercise 2021's incoming fictitious(!) asteroid, 2021 PDC, seems headed for impact on October 20th, 2021, exactly 6 months after its discovery. Today (April 26th, 2021), the impact probability is 5%, in a steep rise from 1 in 2500 upon discovery six days ago. We all know how these things end. Or do we? Unless somebody kicked off another headline-grabbing media scare or wants to keep civil defense very idle very soon, chances are that it will hit (note: this is an exercise!). Taking stock, it is barely 6 months to impact, a steadily rising likelihood that it will actually happen, and a huge uncertainty of possible impact energies: First estimates range from 1.2 MtTNT to 13 GtTNT, and this is not even the worst-worst case: a 700 m diameter massive NiFe asteroid (covered by a thin veneer of Ryugu-black rubble to match size and brightness) would come in at 70 GtTNT. In down to Earth terms, this could be all between smashing fireworks over some remote area of the globe and a 7.5 km crater downtown somewhere. Considering the deliberate and sedate ways of development of interplanetary missions it seems we can only stand and stare until we know well enough where to tell people to pack up all that can be moved at all and save themselves. But then, it could just as well be a smaller bright rock. The best estimate is 120 m diameter from optical observation alone, by 13% standard albedo. NASA's upcoming DART mission to binary asteroid (65803) Didymos is designed to hit such a small target, its moonlet Dimorphos. The Deep Impact mission's impactor in 2005 successfully guided itself to the brightest spot on comet 9P/Tempel 1, a relatively small feature on the 6 km nucleus. And 'space' has changed: By the end of this decade, one satellite communication network plans to have launched over 11000 satellites at a pace of 60 per launch every other week. This level of series production is comparable in numbers to the most prolific commercial airliners. Launch vehicle production has not simply increased correspondingly - they can be reused, although in a trade for performance. Optical and radio astronomy as well as planetary radar have made great strides in the past decade, and so has the design and production capability for everyday 'high-tech' products. 60 years ago, spaceflight was invented from scratch within two years, and there are recent examples of fastpaced space projects as well as a drive towards 'responsive space'. It seems it is not quite yet time to abandon all hope. We present what could be done and what is too close to call once thinking is shoved out of the box by a clear and present danger, to show where a little more preparedness or routine would come in handy - or become decisive. And if we fail, let's stand and stare safely and well instrumented anywhere on Earth together in the greatest adventure of science

Physics Research on the International Space Station

The International Space Station (ISS) is orbiting Earth at an altitude of around 400 km. It has been manned since November 2000 and currently has a permanent crew of six. On-board ISS science is done in a wide field of sciences, from fundamental physics to biology and human physiology. Many of the experiments utilize the unique conditions of weightlessness, but also the views of space and the Earth are exploited. ESA’s (European Space Agency) ELIPS (European Programme Life and Physical sciences in Space) manages some 150 on-going and planned experiments for ISS, which is expected to be utilized at least to 2020. This presentation will give a short introduction to ISS, followed by an overview of the science field within ELIPS and some resent results. The emphasis, however, will be on ISS experiments which are close to the research performed at CERN. Silicon strip detectors like ALTEA are measuring the flux of ions inside the station. ACES (Atomic Clock Ensemble in Space) will provide unprecedented global time accuracy and perform tests of Einstein’s general theory of relativity. SpaceQUEST is proposed to test Bell inequalities for distances over 1000 km and a possible de-coherence effect due to gravity. Q-WEP aims at an atom interferometry test of the weak equivalence principle to a few parts in 10-15 by using samples of ultra-cold atoms, possibly different isotopes of Rb. JEM-EUSO will study the ultra-high energy cosmic rays from space (E>7x10-19 eV) by measuring the fluorescence and Cherenkov radiation they create in the atmosphere. Although AMS was largely built in Europe and tested at an ESA’s facility, it is not part of ELIPS and will only be briefly mentioned

Satellite Image Compression Guided by Regions of Interest

Small satellites empower different applications for an affordable price. By dealing with a limited capacity for using instruments with high power consumption or high data-rate requirements, small satellite missions usually focus on specific monitoring and observation tasks. Considering that multispectral and hyperspectral sensors generate a significant amount of data subjected to communication channel impairments, bandwidth constraint is an important challenge in data transmission. That issue is addressed mainly by source and channel coding techniques aiming at an effective transmission. This paper targets a significant further bandwidth reduction by proposing an on-the-fly analysis on the satellite to decide which information is effectively useful before coding and transmitting. The images are tiled and classified using a set of detection algorithms after defining the least relevant content for general remote sensing applications. The methodology makes use of the red-band, green-band, blue-band, and near-infrared-band measurements to perform the classification of the content by managing a cloud detection algorithm, a change detection algorithm, and a vessel detection algorithm. Experiments for a set of typical scenarios of summer and winter days in Stockholm, Sweden, were conducted, and the results show that non-important content can be identified and discarded without compromising the predefined useful information for water and dry-land regions. For the evaluated images, only 22.3% of the information would need to be transmitted to the ground station to ensure the acquisition of all the important content, which illustrates the merits of the proposed method. Furthermore, the embedded platform’s constraints regarding processing time were analyzed by running the detection algorithms on Unibap’s iX10-100 space cloud platform

Operational radiation protection for astronauts and cosmonauts and correlated activities of ESA Medical Operations

Since the early times of human spaceflight radiation has been, besides the influence of microgravity on the human body, recognized as a main health concern to astronauts and cosmonauts. The radiation environment that the crew experiences during spaceflight differs significantly to that found on earth due to particles of greater potential for biological damage. Highly energetic charged particles, such as protons, helium nuclei (“alpha particles”) and heavier ions up to iron, originating from several sources, as well as protons and electrons trapped in the Earth's radiation belts, are the main contributors. The exposure that the crew receives during a spaceflight significantly exceeds exposures routinely received by terrestrial radiation workers. The European Space Agency's (ESA) Astronaut Center (EAC) in Cologne, Germany, is home of the European Astronaut Corps. Part of the EAC is the Crew Medical Support Office (CMSO or HSF-AM) responsible for ensuring the health and well-being of the European Astronauts. A sequence of activities is conducted to protect astronauts and cosmonauts health, including those aiming to mitigate adverse effects of space radiation. All health related activities are part of a multinational Medical Operations (MedOps) concept, which is executed by the different Space Agencies participating in the human spaceflight program of the International Space Station (ISS). This article will give an introduction to the current measures used for radiation monitoring and protection of astronauts and cosmonauts. The operational guidelines that shall ensure proper implementation and execution of those radiation protection measures will be addressed. Operational hardware for passive and active radiation monitoring and for personal dosimetry, as well as the operational procedures that are applied, are described

Geant4 Monte Carlo simulations of the galactic cosmic ray radiation environment on-board the international space station/columbus

A characterization of the Galactic Cosmic Ray (GCR) induced radiation environment on-board Columbus and the Inter-national Space Station (ISS) has been carried out using the Geant4 Monte Carlo particle transport toolkit and detailed geometry models of Columbus and ISS. Dose and dose equivalent rates, as well as penetrating particle spectra are presented. Simulation results indicate that the major part of the dose rates due to GCR protons are associated with secondary particles produced in the hull of ISS. Neutrons contribute about 15% of the GCR proton dose equivalent rate and mesons about 10%. More than 40% of the simulated GCR proton dose and dose equivalent rates are due to protons in the energy range above 10 GeV. Protons in the energy range above 50 GeV contribute only 5% to the dose rates. The total simulated dose and dose equivalent rates at solar maximum are 63 mu Gy/d and 123 mu Sv/d, respectively. The dose equivalent rate underestimates measurements made during the 2001 solar maximum. The discrepancy can be attributed to deficiencies in hadronic ion-nuclei interaction models for heavy ions and to the lack of such models above 10 GeV/N in Geant4

Geant4 Monte Carlo Simulations of the belt proton radiation environment on board the international space Station/Columbus

A detailed characterization of the trapped-proton-induced radiation environment on board Columbus and the International Space Station (ISS) has been carried out using the Geant4 Monte Carlo particle transport toolkit. Dose and dose equivalent rates, as well as penetrating particle spectra are presented. These results are based on detailed Geant4 geometry models of Columbus and ISS, comprising a total of about 1000 geometry volumes. Simulated trapped-proton dose rates are found to be strongly dependent on ISS altitude. Dose rates for different locations inside the Columbus cabin are presented, as well as for different models of the incident trapped-proton flux. Dose rates resulting from incident anisotropic trapped protons are found to be lower than, or equal to, those of omnidirectional models. The anisotropy induced by the asymmetric shielding distribution of Columbus/ISS is also studied. The simulated trapped-proton dose (equivalent) rates, averaged over different locations inside Columbus, are 120 mu Gy/d (154 mu Sv/d) and 79 mu Gy/d (102 mu Sv/d) for solar minimum and maximum conditions according to AP8 incident proton spectra and an ISS orbit of 380 km. The solar maximum dose rates are found to be of the same order as measurements in other modules in the present ISS

Summary of recent results obtained by the Sileye-3/Alteino detector in the Russian part of the International Space Station as part of the ALTCRISS project

The Sileye3/Alteino experiment is devoted to the investigation of the light flash phenomenon and particle composition of the cosmic ray spectrum inside the ISS. The particle detector is a silicon telescope consisting of eight planes, each divided into 32 strips. Data acquisition was initiated in 2002 in the Russian Pirs module. The data on nuclei from C to Fe in the energy range above about 60 MeV/n presented here were taken as part of the ESA Altcriss project [ 1] from late 2005 through 2007. Here we report on LET, from different locations and orientations, in both the Pirs and Zvezda modules. Taking solar modulation into account the results are in agreement with ALTEA measurements from USLab [ 2]. To convert the energy deposition in Si to the equivalent in water, the logarithmic relation between LET in Si and water adopted from [ 3]. In Fig. 1, the LET spectra in water for Alteino and ALTEA are compared with DOSTEL spectrum from 2001 [ 4], and we see a good overall agreement. We are currently in the process of preparing a detailed paper on the dose and dose equivalent rates in different places inside the Zvezda and Pirs modules and a novel analysis of the contribution to the different doses as a function of strip hit multiplicity

The JEM-EUSO Program for UHECR Studies from Space

International audienceTo take up the challenge of understanding the origin of the ultra-high-energy cosmic rays (UHECRs), new observational means appear necessary. The JEM-EUSO Collaboration has undertaken to open the space road to UHECR studies. For more than a decade, it has been developing a realistic program to measure the UHECRs from space with unprecedented aperture, together with complementary scientific objectives in a broader multidisciplinary context. Several intermediate missions have already been completed (on the ground: EUSO-TA; under stratospheric ballons: EUSO-Balloon and EUSO-SPB1; in space: TUS, and on-board the ISS: MINI-EUSO), and others are in preparation for flight (EUSO-SPB2), under review (K-EUSO: currently on hold), or proposed for the next decade (POEMMA). We report on the general status of the JEM-EUSO program, underlining that its technology has now reached operational maturity, and is ready for actual cosmic-ray shower detection from above