Solar orbiter: mission to study the sun [Space innovation]

Context. The Solar Orbiter spacecraft will be equipped with a wide range of remote-sensing (RS) and in situ (IS) instruments to record novel and unprecedented measurements of the solar atmosphere and the inner heliosphere. To take full advantage of these new datasets, tools and techniques must be developed to ease multi-instrument and multi-spacecraft studies. In particular the currently inaccessible low solar corona below two solar radii can only be observed remotely. Furthermore techniques must be used to retrieve coronal plasma properties in time and in three dimensional (3D) space. Solar Orbiter will run complex observation campaigns that provide interesting opportunities to maximise the likelihood of linking IS data to their source region near the Sun. Several RS instruments can be directed to specific targets situated on the solar disk just days before data acquisition. To compare IS and RS, data we must improve our understanding of how heliospheric probes magnetically connect to the solar disk. Aims. The aim of the present paper is to briefly review how the current modelling of the Sun and its atmosphere can support Solar Orbiter science. We describe the results of a community-led effort by European Space Agency’s Modelling and Data Analysis Working Group (MADAWG) to develop different models, tools, and techniques deemed necessary to test different theories for the physical processes that may occur in the solar plasma. The focus here is on the large scales and little is described with regards to kinetic processes. To exploit future IS and RS data fully, many techniques have been adapted to model the evolving 3D solar magneto-plasma from the solar interior to the solar wind. A particular focus in the paper is placed on techniques that can estimate how Solar Orbiter will connect magnetically through the complex coronal magnetic fields to various photospheric and coronal features in support of spacecraft operations and future scientific studies. Methods. Recent missions such as STEREO, provided great opportunities for RS, IS, and multi-spacecraft studies. We summarise the achievements and highlight the challenges faced during these investigations, many of which motivated the Solar Orbiter mission. We present the new tools and techniques developed by the MADAWG to support the science operations and the analysis of the data from the many instruments on Solar Orbiter. Results. This article reviews current modelling and tool developments that ease the comparison of model results with RS and IS data made available by current and upcoming missions. It also describes the modelling strategy to support the science operations and subsequent exploitation of Solar Orbiter data in order to maximise the scientific output of the mission. Conclusions. The on-going community effort presented in this paper has provided new models and tools necessary to support mission operations as well as the science exploitation of the Solar Orbiter data. The tools and techniques will no doubt evolve significantly as we refine our procedure and methodology during the first year of operations of this highly promising mission.

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Dust observations with antenna measurements and its prospects for observations with Parker Solar Probe and Solar Orbiter

Annales Geophysicae ◽

10.5194/angeo-37-1121-2019 ◽

2019 ◽

Vol 37 (6) ◽

pp. 1121-1140 ◽

Cited By ~ 5

Author(s):

Ingrid Mann ◽

Libor Nouzák ◽

Jakub Vaverka ◽

Tarjei Antonsen ◽

Åshild Fredriksen ◽

...

Keyword(s):

Interplanetary Medium ◽

Subsequent Development ◽

Plasma Waves ◽

The Sun ◽

Electric And Magnetic Field ◽

The Impact ◽

Empirical Approaches ◽

Orbiter Mission ◽

Qualitative Discussion ◽

Inner Heliosphere

Abstract. The electric and magnetic field instrument suite FIELDS on board the NASA Parker Solar Probe and the radio and plasma waves instrument RPW on the ESA Solar Orbiter mission that explore the inner heliosphere are sensitive to signals generated by dust impacts. Dust impacts have been observed using electric field antennas on spacecraft since the 1980s and the method was recently used with a number of space missions to derive dust fluxes. Here, we consider the details of dust impacts, subsequent development of the impact generated plasma and how it produces the measured signals. We describe empirical approaches to characterise the signals and compare these in a qualitative discussion of laboratory simulations to predict signal shapes for spacecraft measurements in the inner solar system. While the amount of charge production from a dust impact will be higher near the Sun than observed in the interplanetary medium before, the amplitude of pulses is determined by the recovery behaviour that is different near the Sun since it varies with the plasma environment.

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Solar observations with the Nancay Radioheliograph in support of the Solar Orbiter and Parker Solar Probe missions

10.5194/egusphere-egu21-7107 ◽

2021 ◽

Author(s):

Karl-Ludwig Klein ◽

Keyword(s):

Active Regions ◽

Data Acquisition System ◽

Total Solar Eclipse ◽

The Sun ◽

Eclipse Observations ◽

Solar Observations ◽

Mass Ejection ◽

Orbiter Mission ◽

Probe Mission ◽

Perihelion Passage

The Nancay Radioheliograph is dedicated to imaging the solar corona at decimetre-to-metre wavelengths. The imaged structures are the quiet corona, through thermal bremsstrahlung, and bright collective emissions due to electrons accelerated in quiescent, flaring and eruptive active regions. The instrument produced nearly daily maps of the Sun between 1996 and 2015, at several frequencies in the 150-450 MHz range with sub-second cadence. The observations were stopped in 2015 for a major technical upgrade through the replacement of the correlator and the data acquisition system. They were resumed in November 2020, and at the time of writing the commissioning of the instrument is well underway. This contribution will give a brief overview of the technical changes and present observations at eight frequencies of solar activity since November 2020, including the coronal mass ejection (CME) of December 14 seen in some images of the total solar eclipse, observations conducted during the present perihelion passage of the Parker Solar Probe mission, as well as during periods of interest to the Solar Orbiter mission. The data are freely available, and special products of common visualisation with the space missions will be illustrated.

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The Solar Orbiter mission – Exploring the Sun and heliosphere

10.5194/egusphere-egu21-2981 ◽

2021 ◽

Author(s):

Daniel Mueller ◽

Yannis Zouganelis ◽

Teresa Nieves-Chinchilla ◽

Chris St. Cyr

Keyword(s):

High Spatial Resolution ◽

Ecliptic Plane ◽

Space Mission ◽

Polar Regions ◽

The Sun ◽

Very High Spatial Resolution ◽

New Perspective ◽

Orbiter Mission ◽

Very High

Solar Orbiter, launched on 10 February 2020, is a space mission of international collaboration between ESA and NASA. It is exploring the linkage between the Sun and the heliosphere and has started to collect unique data at solar distances down to 0.49 AU. By ultimately approaching as close as 0.28 AU, Solar Orbiter will view the Sun with very high spatial resolution and combine this with in-situ measurements of the surrounding heliosphere. Over the course of the mission, the highly elliptical orbit will get progressively more inclined to the ecliptic plane. Thanks to this new perspective, Solar Orbiter will deliver images and comprehensive data of the unexplored Sun&#8217;s polar regions and the side of the Sun not visible from Earth. This talk will highlight first science results from Solar Orbiter and provide a mission status update.

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Solar Orbiter: Europe's mission to the Sun

10.5194/egusphere-egu2020-22164 ◽

2020 ◽

Author(s):

Yannis Zouganelis ◽

Daniel Mueller ◽

Chris St Cyr ◽

Holly Gilbert ◽

Teresa Nieves-Chinchilla

Keyword(s):

High Spatial Resolution ◽

Solar Wind Plasma ◽

Ecliptic Plane ◽

Current Status ◽

Polar Regions ◽

The Sun ◽

Physical Processes ◽

New Perspective ◽

Orbiter Mission

ESA&#8217;s Solar Orbiter mission is scheduled for launch in February 2020, and will focus on exploring the linkage between the Sun and the heliosphere. It is a collaborative mission with NASA that will collect unique data that will allow us to study, e.g., the coupling between macroscopic physical processes to those on kinetic scales, the generation of solar energetic particles and their propagation into the heliosphere, and the origin and acceleration of solar wind plasma. By approaching as close as 0.28 AU, Solar Orbiter will view the Sun with high spatial resolution and combine this with in-situ measurements of the surrounding heliosphere. Over the course of the mission, the highly elliptical orbit will get progressively more inclined to the ecliptic plane. Thanks to this new perspective, Solar Orbiter will deliver images and comprehensive data of the unexplored Sun&#8217;s polar regions and the side of the Sun not visible from Earth. This talk will provide a mission overview, highlight synergies with NASA&#8217;s Parker Solar Probe and summarise current status.

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6. The future of solar physics

The Sun: A Very Short Introduction ◽

10.1093/actrade/9780198832690.003.0006 ◽

2020 ◽

pp. 149-154

Author(s):

Philip Judge

Keyword(s):

Solar Wind ◽

Magnetic Fields ◽

Coronal Mass Ejections ◽

Solar Physics ◽

Solar Telescope ◽

The Sun ◽

New Era ◽

The Future ◽

To Come ◽

Orbiter Mission

Solar physics is a historically data-starved science, but about to becomes less so. ‘The future of solar physics’ looks at new facilities, either online or about to come online, such as the Daniel K. Inouye Solar Telescope on Maui. This aims to see, through measurements of coronal magnetic fields and plasma, how the Sun’s magnetic fields generate flares, coronal mass ejections, and the solar wind. Other major missions include NASA’s Parker Solar Probe and the European Solar Orbiter mission, spacecraft intended to orbit the Sun in new ways and from different viewpoints on Earth. Supported by increasingly powerful computers, these missions are ushering in a new era.

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Dust observations with antenna measurements and its prospects for observations with Parker Solar Probe and Solar Orbiter

10.5194/angeo-2019-94 ◽

2019 ◽

Author(s):

Ingrid Mann ◽

Libor Nouzák ◽

Jakub Vaverka ◽

Tarjei Antonsen ◽

Åshild Fredriksen ◽

...

Keyword(s):

Interplanetary Medium ◽

Subsequent Development ◽

Plasma Waves ◽

The Sun ◽

Spacecraft Potential ◽

The Impact ◽

Empirical Approaches ◽

Orbiter Mission ◽

Qualitative Discussion ◽

Inner Heliosphere

Abstract. The electric and magnetic field instrument suite FIELDS on board the NASA Parker Solar Probe and the radio and plasma waves instrument RPWS on the ESA Solar Orbiter mission that explore the inner heliosphere are sensitive to signals generated by dust impacts. Dust impacts were observed using electric field antennas on spacecraft since the 1980s and the method was recently used with a number of space missions to derive dust fluxes. Here, we consider the details of dust impacts, subsequent development of the impact generated plasma and how it produces the measured signals. We describe empirical approaches to characterise the signals and compare to a qualitative discussion of laboratory simulations to predict signal shapes for spacecraft measurements in the inner solar system. While the amount of charge production from a dust impact will be higher near the sun than observed in the interplanetary medium before, the amplitude of pulses will be lower because of the different recovery behaviour that varies with the plasma environment. The photocurrent, that is expected to be higher near the Sun, is found to have moderate influence on the spacecraft potential.

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The Solar Orbiter EUI instrument: The Extreme Ultraviolet Imager

Astronomy and Astrophysics ◽

10.1051/0004-6361/201936663 ◽

2020 ◽

Vol 642 ◽

pp. A8 ◽

Cited By ~ 10

Author(s):

P. Rochus ◽

F. Auchère ◽

D. Berghmans ◽

L. Harra ◽

W. Schmutz ◽

...

Keyword(s):

High Resolution ◽

Extreme Ultraviolet ◽

Optical Element ◽

Radiation Environment ◽

The Sun ◽

Systematic Effort ◽

Resolution Imaging ◽

Outer Corona ◽

Vantage Points ◽

Orbiter Mission

Context. The Extreme Ultraviolet Imager (EUI) is part of the remote sensing instrument package of the ESA/NASA Solar Orbiter mission that will explore the inner heliosphere and observe the Sun from vantage points close to the Sun and out of the ecliptic. Solar Orbiter will advance the “connection science” between solar activity and the heliosphere. Aims. With EUI we aim to improve our understanding of the structure and dynamics of the solar atmosphere, globally as well as at high resolution, and from high solar latitude perspectives. Methods. The EUI consists of three telescopes, the Full Sun Imager and two High Resolution Imagers, which are optimised to image in Lyman-α and EUV (17.4 nm, 30.4 nm) to provide a coverage from chromosphere up to corona. The EUI is designed to cope with the strong constraints imposed by the Solar Orbiter mission characteristics. Limited telemetry availability is compensated by state-of-the-art image compression, onboard image processing, and event selection. The imposed power limitations and potentially harsh radiation environment necessitate the use of novel CMOS sensors. As the unobstructed field of view of the telescopes needs to protrude through the spacecraft’s heat shield, the apertures have been kept as small as possible, without compromising optical performance. This led to a systematic effort to optimise the throughput of every optical element and the reduction of noise levels in the sensor. Results. In this paper we review the design of the two elements of the EUI instrument: the Optical Bench System and the Common Electronic Box. Particular attention is also given to the onboard software, the intended operations, the ground software, and the foreseen data products. Conclusions. The EUI will bring unique science opportunities thanks to its specific design, its viewpoint, and to the planned synergies with the other Solar Orbiter instruments. In particular, we highlight science opportunities brought by the out-of-ecliptic vantage point of the solar poles, the high-resolution imaging of the high chromosphere and corona, and the connection to the outer corona as observed by coronagraphs.

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The Solar Orbiter mission

Astronomy and Astrophysics ◽

10.1051/0004-6361/202038467 ◽

2020 ◽

Vol 642 ◽

pp. A1 ◽

Cited By ~ 22

Author(s):

D. Müller ◽

O. C. St. Cyr ◽

I. Zouganelis ◽

H. R. Gilbert ◽

R. Marsden ◽

...

Keyword(s):

Remote Sensing ◽

Ecliptic Plane ◽

Trajectory Design ◽

The Sun ◽

Cosmic Vision ◽

Science Operations ◽

Heliospheric Physics ◽

And Performance ◽

Orbiter Mission

Aims. Solar Orbiter, the first mission of ESA’s Cosmic Vision 2015–2025 programme and a mission of international collaboration between ESA and NASA, will explore the Sun and heliosphere from close up and out of the ecliptic plane. It was launched on 10 February 2020 04:03 UTC from Cape Canaveral and aims to address key questions of solar and heliospheric physics pertaining to how the Sun creates and controls the Heliosphere, and why solar activity changes with time. To answer these, the mission carries six remote-sensing instruments to observe the Sun and the solar corona, and four in-situ instruments to measure the solar wind, energetic particles, and electromagnetic fields. In this paper, we describe the science objectives of the mission, and how these will be addressed by the joint observations of the instruments onboard. Methods. The paper first summarises the mission-level science objectives, followed by an overview of the spacecraft and payload. We report the observables and performance figures of each instrument, as well as the trajectory design. This is followed by a summary of the science operations concept. The paper concludes with a more detailed description of the science objectives. Results. Solar Orbiter will combine in-situ measurements in the heliosphere with high-resolution remote-sensing observations of the Sun to address fundamental questions of solar and heliospheric physics. The performance of the Solar Orbiter payload meets the requirements derived from the mission’s science objectives. Its science return will be augmented further by coordinated observations with other space missions and ground-based observatories.

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Chromospheric activity as a function of age in main-sequence stars

Symposium - International Astronomical Union ◽

10.1017/s0074180900053146 ◽

1966 ◽

Vol 24 ◽

pp. 40-43

Author(s):

O. C. Wilson ◽

A. Skumanich

Keyword(s):

Main Sequence ◽

The Sun ◽

Main Sequence Stars ◽

Tentative Conclusion ◽

Chromospheric Activity ◽

General Field ◽

Large Clusters

Evidence previously presented by one of the authors (1) suggests strongly that chromospheric activity decreases with age in main sequence stars. This tentative conclusion rests principally upon a comparison of the members of large clusters (Hyades, Praesepe, Pleiades) with non-cluster objects in the general field, including the Sun. It is at least conceivable, however, that cluster and non-cluster stars might differ in some fundamental fashion which could influence the degree of chromospheric activity, and that the observed differences in chromospheric activity would then be attributable to the circumstances of stellar origin rather than to age.

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