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RSID: <<2023-05-25T23:31Z MFSK-32 @ 9265000+1500>>


Welcome to program 306 of Shortwave Radiogram.

I'm Kim Andrew Elliott in Arlington, Virginia USA.

Here is the lineup for today's program, in MFSK modes as noted:

  1:40 MFSK32: Program preview (now)
  2:45 MFSK32: High-speed orbital data using lasers
  6:56 MFSK64: Tonga volcano disrupted satellite communications
11:02 MFSK64: This week's images
28:39 MFSK32: Closing announcements

 

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From New Atlas:

High-speed orbital data link drags space communications out of
the '60s

By David Szondy
May 22, 2023

Finally, a promising upgrade to the antique space radio systems
that make orbital data transfer so ridiculously slow. Terran
Orbit has set a new record for transmitting at high-speed from
space to Earth as NASA's Pathfinder Technology Demonstrator 3
(PTD-3) CubeSat used an optical laser system to beam data from
300 miles (480 km) up to a ground station at a rate of 200
gigabits per second.

The advance of space travel since the first Sputnik launch in
1957 has been one of paradox. Humanity has gone from lofting
crude orbital packages that couldn't do more than go "beep beep"
with monotonous regularity, to sending robotic rovers to Mars,
probing the atmospheres of Jupiter and Titan, visiting every
planet in the solar system, and sending our uncrewed emissaries
on one-way voyages into interstellar space.

Despite this, space communications have been stuck decades in the
past, still relying on X-band radio. Set at 7.25 GHz to 7.75 GHz
and 7.9 GHz to 8.4 GHz, it has been the standard for satellite
transmissions for a number of reasons – not the least of which is
that it can penetrate through water-laden clouds.

However it also has ridiculously little bandwidth. The rates vary
with transmitter and receiver configuration, but a 45-cm (18-in)
antenna can achieve a data rate of 10 Mbit/s and the Hubble Space
Telescope can only handle about 10 terabytes per year.

To overcome this, NASA and its commercial partners are developing
laser-based alternatives. In this case, the TeraByte InfraRed
Delivery (TBIRD) payload, which is funded by the NASA Space
Communications and Navigation (SCaN) and developed by the MIT
Lincoln Laboratory.

According to Terran Orbital, this new capability will allow
satellites to transmit terabytes of data with each pass over a
ground station. In addition it will allow for major advances in
existing technologies, including space-based earth observation
systems and synthetic aperture radars.

"The completion of the 200 gigabits per second link is both
monumental and record-breaking," said Marc Bell, Terran Orbital's
Co-Founder, Chairman and Chief Executive Officer. "Terran Orbital
is honored to have worked alongside NASA on this groundbreaking
mission and is grateful to MIT Lincoln Laboratory for creating
the payload. We look forward to working with NASA and MIT Lincoln
Laboratory on future satellites as we continue to make
record-breaking in space commonplace."

Source: Terran Orbital

https://newatlas.com/space/orbital-data-link-space-communications/

 

Shortwave Radiogram now changes to MFSK64 ...

 

RSID: <<2023-05-25T23:37Z MFSK-64 @ 9265000+1500>>


This is Shortwave Radiogram in MFSK64

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From Phys.org:

Eruption of Tonga underwater volcano found to disrupt satellite
signals halfway around the world

by Nagoya University
May 22, 2023

An international team has used satellite- and ground-based
ionospheric observations to demonstrate that an air pressure wave
triggered by volcanic eruptions could produce an equatorial
plasma bubble (EPB) in the ionosphere, severely disrupting
satellite-based communications. Their findings were published in
the journal Scientific Reports.

The ionosphere is the region of the Earth's upper atmosphere
where molecules and atoms are ionized by solar radiation,
creating positively charged ions. The area with the highest
concentration of ionized particles is called the F-region, an
area 150 to 800 kilometers above the Earth's surface. The
F-region plays a crucial role in long-distance radio
communication, reflecting and refracting radio waves used by
satellite and GPS tracking systems back to the Earth's surface.

These important transmissions can be disrupted by irregularities
in the F-region. During the day, the ionosphere is ionized by the
Sun's ultraviolet radiation, creating a density gradient of
electrons with the highest density near the equator. However,
disruptions to this, such as the movement of plasma, electric
fields, and neutral winds, can cause the formation of a localized
irregularity of enhanced plasma density. This region can grow and
evolve, creating a bubble-like structure called an EPB. EPB can
delay radio waves and degrade the performance of GPS.

Since these density gradients can be affected by atmospheric
waves, it has long been hypothesized that they are formed by
terrestrial events such as volcanic activity. For an
international team led by Designated Assistant Professor Atsuki
Shinbori (he, him) and Professor Yoshizumi Miyoshi (he, him) of
the Institute for Space–Earth Environmental Research (ISEE),
Nagoya University, in collaboration with NICT, The University of
Electro-Communications, Tohoku University, Kanazawa University,
Kyoto University and ISAS, the Tonga volcano eruption [January
2022] offered them a perfect opportunity to test this theory.

The Tonga volcano eruption was the biggest submarine eruption in
history. This allowed the team to test their theory using the
Arase satellite to detect EPB occurrences, the Himawari-8
satellite to check the initial arrival of air pressure waves and
ground-based ionospheric observations to track the motion of the
ionosphere. They observed an irregular structure of the electron
density across the equator that occurred after the arrival of
pressure waves generated by the volcanic eruption.

"The results of this study showed EPBs generated in the
equatorial to low-latitude ionosphere in Asia in response to the
arrival of pressure waves caused by undersea volcanic eruptions
off Tonga," Shinbori said.

The group also made a surprising discovery. For the first time,
they showed that ionospheric fluctuations start a few minutes to
a few hours earlier than the atmospheric pressure waves involved
in the generation of plasma bubbles. This could have important
implications because it suggests that the long-held model of
geosphere-atmosphere-cosmosphere coupling, which states that
ionospheric disturbances only happen after the eruption, needs
revision.

"Our new finding is that the ionospheric disturbances are
observed several minutes to hours before the initial arrival of
the shock waves triggered by the Tonga volcanic eruption,"
Shinbori said. "This suggests that the propagation of the fast
atmospheric waves in the ionosphere triggered the ionospheric
disturbances before the initial arrival of the shock waves.
Therefore, the model needs to be revised to account for these
fast atmospheric waves in the ionosphere."

They also found that the EPB extended much further than predicted
by the standard models. "Previous studies have shown that the
formation of plasma bubbles at such high altitudes is a rare
occurrence, making this a very unusual phenomenon," Shinbori
said. "We found that the EPB formed by this eruption reached
space even beyond the ionosphere, suggesting that we should pay
attention to the connection between the ionosphere and the
cosmosphere when extreme natural phenomenon, such as the Tonga
event, occur."

"The results of this research are significant not only from a
scientific point of view but also from the point of view of space
weather and disaster prevention," he said. "In the case of a
large-scale event, such as the Tonga volcano eruption,
observations have shown that a hole in the ionosphere can form
even under conditions that are considered unlikely to occur under
normal circumstances. Such cases have not been incorporated into
space weather forecast models. This study will contribute to the
prevention of satellite broadcasting and communication failures
associated with ionospheric disturbances caused by earthquakes,
volcanic eruptions, and other events."

https://phys.org/news/2023-05-eruption-tonga-underwater-volcano-disrupt.html

See also:
https://www.space.com/tonga-undersea-volcano-eruption-disrupted-satellite-signals


 

This is Shortwave Radiogram in MFSK64

Please send your reception report to radiogram@verizon.net
 

Competitors pass a poppy field during the Giro d'Italia 2023
cycling race near Venice. https://t.ly/IyKq

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The sun rises behind the Empire State Building in New York City
and (closer) the Lackwanna clock tower in Hoboken, New Jersey, on
as seen from Jersey City, New Jersey, May 15. https://t.ly/zZhN
...

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The Popocatépetl volcano near Puebla, Mexico. https://t.ly/cZI_
...

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Artist and designer Morag Myerscough in front of the exterior
wall of a freestanding installation during Clerkenwell Design
Week in London. https://t.ly/nPe_ ...

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Lightscape, at the Royal Botanic Garden, is part of the Vivid
2023 light festival in Sydney. https://t.ly/5jL9O ...

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A raven lands on the roof of a barn in Cremona, Alberta, as thick
smoke from wildfires obscures the sun. https://t.ly/nto- ...

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From the BBC's "your pictures on the theme of 'three colours'."
https://t.ly/o0JP ...

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Sunset at Silver Beach on Lake Michigan in St. Joseph, Michigan.
https://t.ly/S_HUf ...

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The orange blend hybrid tea rose 'Tina Turner,' hybridized in the
1990s. https://t.ly/zcyUP ...

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Our painting of the week is "Lilacs" (2017) by Gerard Collins.
https://t.ly/9Cv2t ...

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Shortwave Radiogram returns to MFSK32 ...


 

RSID: <<2023-05-25T23:58Z MFSK-32 @ 9265000+1500>>