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Russian Cosmonaut Oleg Artemyev's Sept 3, 2018 tweet has a narrated video of Earth from the ISS, at the time over the Nile river.

The video is also in YouTube (below).

At the bottom of the screen, shown in the screenshot below, there are what looks like two antennas, one on either side. They are in space and faciing towards the Earth. They might also be supports for other sensors, or something else entirely.

What are these structures called and what are their functions?

"bonus points" for identifying the name and location of the window where this was being filmed (perhaps this?)

below: Screenshot of the tweeted video. Click for full size.

enter image description here

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They appear to be associated with a plasma wave experiment called Obstanovka (lower left of this picture, in red). Source is this presentation.

enter image description here

More info on the experiment, and this image, here. (This web page is an interesting mash-up of English, Japanese, and Russian!)

enter image description here

Bonus: I believe the video was shot through the 16-inch Service Module window 9, the one you link to in the question. In the first image in my answer, this window and its cover are shown surrounded by purple color.

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To supplement @OrganicMarble's answer, there is a copy of a summary paper of the experiment “Obstanovka” Experiment Onboard International Space Station for Space Weather Research. Still looking for a proper citation, but here is an overview from Section 2:

The goals of “OBSTANOVKA-1” experiment can be formulated as follows:

  • study of plasma-wave processes arising in NSZ from the interaction of superlarge SC with the ionosphere;
  • improvement of Combined Wave Diagnostics (CWD) method of ionosphere plasma flows fluctuation on superlarge and long-lifetime SC;
  • identification of plasma flows disturbance sources and electromagnetic fields in NSZ;
  • geophysical research of plasma-wave processes connected to solar - magnetosphere - ionosphere - atmosphere - lithosphere interactions;
  • ecological monitoring of low-frequency electromagnetic radiation of anthropogenic character, and also connected with global hazard;
  • study of environmental plasma and electromagnetic fields disturbance levels from the injection of electron and plasma beams from ISS and mechanisms of artificial electromagnetic waves distribution;
  • study of the mass characteristics of heavy molecular ions (NO+ and O2+) in NSZ of ISS on the basis of the measured VLF noise and plasma concentration data;
  • research of space weather conditions in equatorial, middle-latitude and sub-aurora ionosphere.

The performance of the “OBSTANOVKA-1” experiment will permit us also to solve the following tasks of applied and fundamental importance:

  • to determine spectral density of electromagnetic, electrostatic and magnetic fields fluctuations in a range of frequencies from fractions of hertz up to tens megahertz resulting from the influence of the various natural NES factors and also from an artificial origin;
  • to measure vectors of intensity of magnetic fields and field-aligned currents (FACs);
  • to determine spectral fluctuation of the charged particles flows and density;
  • to estimate the change of distribution of electromagnetic waves in the disturbed ionosphere, caused by an ISS electromagnetic background and influence of active means, and also to estimate the range of electromagnetic disturbance of ionosphere around ISS;
  • to estimate the conformity of measured electromagnetic fields to the operational requirements of space engineering products and technology, service systems and useful payload;
  • to analyze the concentration of ionosphere plasma close to ISS.

The developed PWC scientific equipment is designed to measure in NES the following physical parameters:

  • current parameters of thermal plasma (in two points):
  • electrons and ions temperature, Te, Ti,
  • electrons and ions density, Ne, Ni;
  • current electromagnetic parameters (in two points):
  • DC electric and magnetic fields and currents;
  • AC electric and magnetic fields and currents;
  • current plasma potential and ISS potential;
  • electrons spectra with energy range 0,01-10 keV;
  • spectra of VLF electromagnetic fluctuations.

For the study of discharge effects in NES plasma the PWC structure includes also the device for discharge stimulation.

The experiment is quite complex! The paper has sections covering the following components. There are numerous figures and diagrams as well:

3.1.Langmuir Probe (LP)

The LP development is funded by National Space Program of Bulgaria. It is scheduled to be available for flight to the end of 2004. The given electrostatic probes have operated aboard numerous “Intercosmos” satellites, heavy geophysical rockets “Vertical”, and have been included in the payload of Mars-96 mission.

3.2.The potential difference measurements instrument (DP)

The potential difference measurement between a probe and ISS body is the main scientific aim of the device DP. This allows us to study of the ISS electric charging processes and the time variation of the electric potential. The existence of two identical devices DP1-1 and DP1- 2, which are mounted on every block CWD, allows us also to measure the spatial electric field in NSZ. The potential difference can be measured in the range ± 200 V. The existence of such high potential values admits charging mechanisms, different from collecting of conducting particles in the plasma. The device DP also provides an estimation of the contact layer resistance of the system plasma – probe. If there is an opportunity for the probe to be replaced by an astronaut, this will permit the study of the influence of the probe geometric and constructional characteristics on the potential difference measurement.

The device DP is an electronic module which measures the potential difference in range ± 200 V, which is divided in two sub-ranges: ± 20V and ± 200 V. The subranges are switched automatically. A 12-bit ADC (Fig. 3) provides potential difference measurements with resolution 10 mV (± 20 V) and 100 mV (± 200 V).

The device DP has three main operational modes:

  • ‘monitoring’ - measurement frequency of 1 Hz;
  • ‘event’ - measurement frequency OF 512 Hz;
  • ‘research’ - a selectable frequency of the measurements.

3.3 Correlating Electron Spectrograf 10eV – 10KeV (CORES)

The main purpose of the CORES is to study the electron population in the ISS vicinity. Electron velocity distribution functions are measured in fast time resolution as well as kilo-Hertz and Mega-Hertz modulations in the electrons resulting from waveparticle interactions. Electrons in the energy range 10eV up to 10keV are measured over a 360o field of view (FOV) with energy spectra resolved at typically at ~0.1s time resolution with simultaneous measurements of electron modulations in the frequency ranges: 0-10MHz (HF); 0-10kHz (VLF); and 0-150Hz (ELF). The CORES is a single module containing all of the components necessary for electron energy resolving and electron detection via microchannel plates (MCP) with associated High Voltage supplies (HV) and includes fast processing using field programmable gate arrays (FPGA) with a microcontroller Data Processing Unit (DPU) interfacing to the Telemetry (TM) and Telecommand (TC) interfaces, I/F of the On-Board Data Handling Unit, OBDH (Fig. 4).

3.4 Combined Wave Sensor

Combined wave sensors CWS1, CWS2 (LEMI-603) are intended for measurement of one component of magnetic field variations (B-channel), current density (I-channel) and electric potential (E-channel) of ionosphere space plasma. An additional channel for measurement of the sensor block temperature is included. Each of probes consists of two units. The first unit is a block of sensors CWD-PS and the second one is the set of electronic unit CWD-SC. The CWD operation block diagram is given on Fig. 5.

3.5.Flux-gate magnetometer DFM2

According to project requirements, a new model of space magnetometer DFM2 (LEMI-012) is developed. The magnetometer LEMI-012 is intended for automatic measurement of three components of DC magnetic field induction. The instrument represents measurements results in the digital form, has high accuracy of measurements and linearity, and has builtin correction of temperature error. It allows receiving authentic information about temporal variations of the Earth magnetic field vector components in orbital flight.

3.6.FLUX-GATE MAGNETOMETER DFM1.

DFM1 is one of two magnetometer using in the PWC of scientific instrumentation The instrument is three components flux-gate magnetometer measuring DC magnetic field induction. The measurement has high accuracy of measurements and linearity. Beside three components DC field the instrument give possibility to get data about magnetic field pulsation and fluctuation (one component) in five frequency band: 55, 110, 165, 400 and 800 Hz. There is possibility to use additionally two bands. The wide of bands is 10 Hz. The measurements region in the band is 0.1 – 100 nT.

3.7 SAS3 Instrument:

The continuous monitoring of ULF-VLF electromagnetic environment on board of ISS by an advanced SAS system (SAS3-ISS) and by simultaneous ground based measurements in ULF-VLF bands is important in the following areas: a) Investigation and verification of the direction of Poynting vector, wave normal and wave energy propagation, using the whole SAS3-ISS configuration. b) The investigation of the possible relationship between the seismic activity and ULF-VLF phenomena that may be related to earthquake events. c) The continuous monitoring of general ULF-ELFVLF activity in the near-Earth space ─ including ELF-VLF pollution. d) The monitoring of natural and man-made variations of the plasmasphere by whistlers. e) Investigation of electromagnetic background and space weather phenomena. f) Investigation of the effect of the large ISS structure to the propagating wave-front. The SAS3-ISS is a complex measuring system containing five main parts in the final configuration. This system measures, digitizes the incoming ULFELF-VLF signals in the 1 Hz − 25 kHz frequency range (at the actual position of ISS) using high and low sampling rates.

3.8.Digital radio-frequency analyzer (RFA):

The main purpose of this instrument is to measure natural and man-made electromagnetic emissions in the frequency range 100 kHz up to 15 MHz. This frequency range covers high frequency whistler waves, Langmuir and upper hybrid modes of the natural plasma. Thus, this instrument can be used as a versatile device for studying nonlinear effects of local plasma resonances, radio transmissions from the ground, and ISS generated noise in the above mentioned frequency range. The station-generated noise is largely unknown, and therefore the investigation in this area could bring interesting results with both scientific as well as technical aspects. Particularly, it is expected that interference between station-generated electromagnetic emissions and natural local resonances in plasma could provide new, unknown results. This instrument is a joint enterprise between the Space Research Centre in Warsaw, Poland and the Swedish Institute of Space Physics in Uppsala, Sweden. New digital technology of this instrument makes a fully programmable device that can be easily adapted to any scientific/technical objectives and telemetry capabilities. The functional block diagram of RFA is shown on Figure 8. and instrument main characteristic is given on Table 8.

3.9.Plasma discharge stimulator (SPP):

SPP is the original tool for realization of calibration practically of all PWC sensors. The electrical discharge gives a wide spectrum of electromagnetic radiation and also is a source of the accelerated particles. The concrete parameters SPP will be fulfilled during tests of laboratory models of the PWC sensors.


From dtic.mil: Report on FA8655-08-1-3006 Langmuir probes for “Obstanovka" Experiment Aboard the Russian Segment of the International Space Station; August 04, 2010

It's a technical summary of some of the electronics and signal processing. Here is a list of some references mentioned:

Presentations Acknowledging Grant FA8655-08-1-3006

  1. Kirov B., Batchvarov D., Krasteva R., Boneva A., Nedkov R., Klimov V., Grushin V., Georgieva K. An instrument for measuring the electrostatic charging of the International Space Station depending on space weather, Year of Astronomy: Solar and SolarTerrestrial Physics 2009, Proceedings of the All-Russian Yearly Conference on Solar Physics, 11-15 July 2009, St. Petersburg, Russia, p.67, ISSN, 0552-5829

  2. Kirov B., Batchvarov D., Krasteva R., Boneva A., Nedkov R., Klimov S., Grushin V., Langmuir probes for the International Space Station, IAGA 11th Scientific Assembly Sopron, Hungary 24-29 August, 2009 abstract No 306-THU-P1700-0316

  3. Kirov B., Space weather effects on surface charging of space vehicles, and an instrument for measuring the surface charging of the International Space Station. Conference “Heliophysical Phenomena and Earth’s Environment”, 7-13 September 2009, Sibenik, Croati,a http://www.zvjezdarnica.hr/meeting, abstract book p.24

  4. Kirov B., Georgieva K., Vassilev V., Spacecraft Charging and an Instrument for its monitoring aboard the International Space Station, 2010 EOS/ESD Symposium, October 3-8, 2010, John Ascuaga's Nugget Resort, Sparks (Reno), NV Abstract Accepted #71 http://www.esda.org/documents/2010SymposiumProgram.pdf

Papers Written and Submitted for Peer Review Acknowledging Grant FA8655-08- 1-3006

  1. Kirov B., „An instrument for measuring the surface charging of the International Space Station”, to be published in a special issue of Bulletin of the Faculty of Science, Cairo University, ISSN 1110-0966 with Proceedings of the IAGA Symposium “Space Weather and its Effects on Spacecraft”, October 5-9, 2008.

  2. Kirov B. “Space weather effects on surface charging of space vehicles, and an instrument for measuring the surface charging of the International Space Station.” Sun and Geosphere, ISSN 1819-0839, in press 2010


There is also an English version of a website for the experiment here: http://www.iki.rssi.ru/obstanovka/eng/index.htm and a description is as follows; from https://www.energia.ru/en/iss/researches/study/05.html

Obstanovka Experiment

Objective:

  • Organization and support of ecological low-frequency electromagnetic monitoring of environmental disturbances based upon facilities and hardware; taking plasma-wave measurements onboard the ISS under basic research programs devoted to Sun-Earth relations in the most active ionospheric area - F2 layer.

  • Generation of experimental database on Earth ionospheric electromagnetic state in order to detect and prevent its disastrous changes.

Tasks:

  1. Determining spectral density of electromagnetic, electrostatic and magnetic fields in the frequency range from a fraction of Hz to tens of megaHz in the stage of single-axis measurements on exposure to different orbital flight factors, including effects of artificial origin.

  2. Measurements of Earth magnetic field intensity vectors along flight course.

  3. Determining plasma particles flow density fluctuation spectra.

Scientific equipment in use:

  • Plasma-wave complex (PWC).

  • PWC complex incorporates KVD1 and KVD2 units attached to adapters and a set of sensors accommodated on two collapsible rods, as well as telemetry information storage unit (TISU) with replaceable recorder unit (RRU).

Expected results:

  • Study of the problem of ensured long-term sustained operation of superlarge SC in orbit by analyzing sufficiently large quantity of accumulated full-scale experimental data on electromagnetic environment (EME).

Experiment Results:

  • Service and scientific TMI downlinked to the ground over БИТС 2-12 channels, as well as recorded on БСПН hard disk and replaceable recorder unit (RRU).
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