1. Monday, June 1, 2020; 7 pm PDT (9 pm CDT, 10 pm EDT: No special programming.
2. Tuesday, June 2, 2020; 7 pm PDT (9 pm CDT, 10 pm EDT): We welcome space engineerDr. Dana Andrews for his new book, Chasing The Dream, which “tells what really happened in our space program over the past 50 years”.
3. Wednesday, June 3, 2020: Hotel Mars TBA pre-recorded. See upcoming show menu on the home page for program details.
4. Thursday, June 4, 2020; 7-8:30 pm PDT (9-10:30 pm CDT, 10-11:30 pm EDT): No special programming.
5. Friday, June 5, 2020; 9:30-11 am PDT (11:30 am-1 pm CDT, 12:30-2 pm EDT): We welcome CEO Jaume Sanpera of Sateliot, a 5G Spanish company that aims to be “the first satellite telecom operator for global continuous IoT connectivity merging satellite and terrestrial networks under 5G protocol“.
6. Sunday, June 7, 2020; 12-1:30 pm PDT (3-4:30 pm EDT, 2-3:30 pm CDT): Welcome to OPEN LINES. All calls welcome, first time callers welcome. Space, STEM, STEAM, science, policy. Join the discussion.
** Fri. 05/29/2020 – Professor Madhu Thangavelu “spoke about SpaceX, returning to the Moon, commercial space, the USC back to school opening plans due to Covid 19 and more”.
discussed the SpaceX Demo-2 Crewed Dragon flight planned for the ISS but which was cancelled due to weather issues. I discussed what was shown for the mission on most all TV channels as the global interest in the mission and the launch was significant. During this short one segment 10 minute discussion, you will come away with a brief but accurate description of the SpaceX production for this launch. Those of you familiar with NASA launches, compare and contrast this SpaceX launch to what you saw for Apollo and later the Shuttle
** Tues.05/26/2020 – Dr. Michael Weil talked about “radiation exposure in deep space, cancer, NASA radiation requirements, strategies and more”. (See slides (pdf) discussed during the program.)
Astronomers using ESO telescopes have discovered giant spots on the surface of extremely hot stars hidden in stellar clusters, called extreme horizontal branch stars. This image shows an artist’s impression of what one of these stars, and its giant whitish spot, might look like. The spot is bright, takes up a quarter of the star’s surface and is caused by magnetic fields. As the star rotates, the spot on its surface comes and goes, causing visible changes in brightness.
Astronomers using European Southern Observatory (ESO) telescopes have discovered giant spots on the surface of extremely hot stars hidden in stellar clusters. Not only are these stars plagued by magnetic spots, some also experience superflare events, explosions of energy several million times more energetic than similar eruptions on the Sun. The findings, published today in Nature Astronomy, help astronomers better understand these puzzling stars and open doors to resolving other elusive mysteries of stellar astronomy.
The team, led by Yazan Momany from the INAF Astronomical Observatory of Padua in Italy, looked at a particular type of star known as extreme horizontal branch stars — objects with about half the mass of the Sun but four to five times hotter.
“These hot and small stars are special because we know they will bypass one of the final phases in the life of a typical star and will die prematurely,” says Momany, who was previously a staff astronomer at ESO’s Paranal Observatory in Chile. “In our Galaxy, these peculiar hot objects are generally associated with the presence of a close companion star.”
Spots on extreme horizontal branch stars (right) appear to be quite different from the dark sunspots on our own Sun (left), but both are caused by magnetic fields. The spots on these hot, extreme stars are brighter and hotter than the surrounding stellar surface, unlike on the Sun where we see spots as dark stains on the solar surface that are cooler than their surroundings. The spots on extreme horizontal branch stars are also significantly larger than sunspots, covering up to a quarter of the star’s surface. While sunspots vary in size, a typical size is around an Earth-size planet, 3000 smaller than a giant spot on an extreme horizontal branch star.
Surprisingly, however, the vast majority of these extreme horizontal branch stars, when observed in tightly packed stellar groups called globular clusters, do not appear to have companions. The team’s long-term monitoring of these stars, made with ESO telescopes, also revealed that there was something more to these mysterious objects. When looking at three different globular clusters, Momany and his colleagues found that many of the extreme horizontal branch stars within them showed regular changes in their brightness over the course of just a few days to several weeks.
“After eliminating all other scenarios, there was only one remaining possibility to explain their observed brightness variations,” concludes Simone Zaggia, a study co-author from the INAF Astronomical Observatory of Padua in Italy and a former ESO Fellow: “these stars must be plagued by spots!”
Spots on extreme horizontal branch stars appear to be quite different from the dark sunspots on our own Sun, but both are caused by magnetic fields. The spots on these hot, extreme stars are brighter and hotter than the surrounding stellar surface, unlike on the Sun where we see spots as dark stains on the solar surface that are cooler than their surroundings. The spots on extreme horizontal branch stars are also significantly larger than sunspots, covering up to a quarter of the star’s surface. These spots are incredibly persistent, lasting for decades, while individual sunspots are temporary, lasting only a few days to months. As the hot stars rotate, the spots on the surface come and go, causing the visible changes in brightness.
Beyond the variations in brightness due to spots, the team also discovered a couple of extreme horizontal branch stars that showed superflares — sudden explosions of energy and another signpost of the presence of a magnetic field.
“They are similar to the flares we see on our own Sun, but ten million times more energetic,” says study co-author Henri Boffin, an astronomer at ESO’s headquarters in Germany. “Such behaviour was certainly not expected and highlights the importance of magnetic fields in explaining the properties of these stars.”
After six decades of trying to understand extreme horizontal branch stars, astronomers now have a more complete picture of them. Moreover, this finding could help explain the origin of strong magnetic fields in many white dwarfs, objects that represent the final stage in the life of Sun-like stars and show similarities to extreme horizontal branch stars.
“The bigger picture though,” says team member, David Jones, a former ESO Fellow now at the Instituto de Astrofísica de Canarias, Spain, “is that changes in brightness of all hot stars — from young Sun-like stars to old extreme horizontal branch stars and long-dead white dwarfs — could all be connected. These objects can thus be understood as collectively suffering from magnetic spots on their surfaces.”
To arrive at this result, the astronomers used several instruments on ESO’s Very Large Telescope (VLT), including VIMOS, FLAMES and FORS2, as well as OmegaCAM attached to the VLT Survey Telescope at Paranal Observatory. They also employed ULTRACAM on the New Technology Telescope at ESO’s La Silla Observatory, also in Chile. The breakthrough came as the team observed the stars in the near-ultraviolet part of the spectrum, allowing them to reveal the hotter, extreme stars standing out bright amongst the cooler stars in globular clusters.
Red Giant stripped of mass during encounter with a black hole, leaving only a white dwarf in orbit. At closest point of its orbit, material from the white dwarf is pulled away by the black hole, resulting in X-ray pulses seen by Chandra X-Ray telescope. Credits: Chandra Observatory via Carnival of Space.
Here is the latest episode in NASA’s Space to Ground weekly report on activities related to the International Space Station:
** Some Space News – ISS/NASA Johnson
Space Anchor Chris Cassidy is here to deliver Some Space News🌠 It’s a big week for the crew on the International Space Station! They’ve had some dynamic operations on Station, and there’s more to come with the awaited arrival of NASA Astronauts Doug Hurley and Bob Behnken on the SpaceX Crew Dragon vehicle. Stay tuned for more space news and watch #LaunchAmerica Saturday May 30 at 3:22pm ET!
** Down to Earth – Some Place Special – NASA Johnson
“It is heart-stopping, it is soul-pounding, it is breathtaking.” In this episode of “Down to Earth – Some Place Special,” NASA Astronaut and Flight Director TJ Creamer discusses the impact of viewing the Earth’s natural wonders from space. #SpaceStation20th
** HTV-9 capture – SciNews
JAXA’s H-II Transfer Vehicle “KOUNOTORI9” (HTV-9) was captured with the International Space Station’s robotic Canadarm2 by Expedition 63 Commander Chris Cassidy of NASA, with assistance from Russian Flight Engineer Ivan Vagner of Roscosmos, on 25 May 2020, at 12:13 UTC 08:13 EDT. Kounotori 9 (こうのとり9) , meaning white stork in Japanese, was launched by JAXA’s H-IIB Launch Vehicle No. 9 (H-IIB F9, ロケット9) from the Yoshinobu Launch Complex, at JAXA’s Tanegashima Space Center, Japan, on 20 May 2020, at 17:31 UTC (21 May, at 02:31 Japan Standard Time – JST) and delivers a total of 6.2 metric tons of supplies, including six new lithium-ion batteries, to the International Space Station.
… you are asked to develop an algorithm to detect Geostationary orbiting objects from simple png images (or frames) acquired by an unknown, low-cost ground-based telescope. Can you learn on how to cope with cloud cover, atmospheric/weather effects, light pollution, sensor noise/defects, star occlusions and more?
Check out the problem description, the dataset and the starter-kit (the dataset and the starter kit will only be available at the competition start date).
The start date is June 8, 2020. Here’s the official announcement from ESA:
“Artificial objects in or near geostationary orbit appear stationary or nearly stationary compared to the background stars, which appear to move due to Earth’s rotation, as shown in this sequence of observed images.” Credits: ESA/Univ. Adelaide
ESA’s latest public competition challenges ‘citizen scientists’ to combine AI with observations from low-cost telescopes to pick out mystery objects in and around geostationary orbit, thousands of kilometres above Earth.
Geostationary orbit is also known as the ‘Clarke belt’ – science fiction writer Sir Arthur C Clarke forecast it back in 1945. The further up that satellites orbit, the slower they need to travel to overcome Earth’s gravity. Orbiting at approximately 36 000 km altitude directly above the equator, satellite velocity precisely matches Earth’s rotation, enabling them hover above the same spots in the sky.
The result has been called the most valuable real estate in our solar system: a 265 000 km ring of telecommunications, meteorology and other satellites around our planet, carefully regulated by the International Telecommunication Union.
Despite its economic value however, geostationary orbit – as well as adjacent ‘geosynchronous’ orbits – must contend with the same problems of space debris also seen in lower orbits. ESA and other space agencies perform regular monitoring to identify and track potentially-hazardous debris items. This is usually done using either high-power radar or high-performance astronomical telescopes.
“Geostationary orbit is generally well managed and documented, partly because of its immense practical and commercial value,” notes Tat-Jun Chin of the University of Adelaide, partnering with ESA on the competition. “However, precisely because of that value we should put more efforts into further understanding and protecting it.”
Dario Izzo of ESA’s Advanced Concepts Team (ACT) adds:
“So, for our new ‘spotGEO’ competition, we want to see how well low-cost telescopes combined with tailored AI algorithms can identify ‘resident space objects’ at these altitudes.”
Competition entrants will receive a dataset made up of sets of five sequential images of unspecified segments of the geostationary belt, then challenged to pick out artificial objects against the surrounding stars.
This small telescope at the Univ. of Adelaide was used to “gather imagery of geostationary artificial objects for ESA’s GEOspot competition”. Credits: Univ. Adelaide/ESA
In theory this is made easier because such objects will remain static (or nearly static) compared to the background starfield, which appears to move because of Earth’s rotation. In practice, with atmospheric distortion and an approximately 40-second exposure time for each single image the objects will be smeared out and dimmed. Clouds, light pollution and sensor noise also add to the challenge.
“The sheer distance between the observer and the target objects makes this a difficult problem,” adds Dario.
“Each pixel observed at this altitude corresponds to an arc length of about 800 m – so the objects of interest are much smaller than a single pixel. But success should help us keep better watch on this essential region of space around our planet.”
Tat-Jun Chin and his team made contact with the ACT after winning the Pose Estimation Challenge, their previous space-themed AI competition, on estimating the orientation of distant satellites from a dataset of still images.
“Deep learning algorithms can be trained through such datasets to detect visual features of interest,” he notes. “Researchers in AI – particularly computer vision and machine learning – understand that having common datasets is vital towards making progress. These allow different methods to be compared objectively, so that the community can learn the best practices then apply them for their respective problems.
“Generally speaking, sharing datasets in space research is not so common, but the excellent Kelvins competitions are changing this, and after getting to know the ACT we decided to contribute our own.”
The University of Adelaide team coincidentally acquired these images during an observing campaign during the last Australian summer, so that forest fire smoke adds to the observing difficulty.
This is the latest competition hosted at the ACT’s Kelvins website, named after the temperature unit of measurement – with the idea that competitors should aim to reach the lowest possible error, as close as possible to absolute zero. The spotGEO dataset will be available there from 8 June, at the start of the three-month competition.
