NUMBER THEME
Social networks

With old and new friends

The total number of users of all social networks in the world may be equal to the number of people on Earth, given that many of us use multiple social networks, even if we do not think of them that way.
Social networking, as we know it today, stems from a fundamental human need to connect with others. Its early origins can be traced back to the exchange of letters in Mesopotamia and ancient Egypt, while its technological predecessor was the telegraph, which emerged in the first half of the 19th century. While advancements in computer technology have significantly contributed to social networking, the development of an accessible Internet has been even more crucial.
Social networking and social media are overlapping concepts; however, social networking typically refers to the creation of communities by users, while "social media" often pertains specifically to platforms where users share information, ideas, personal messages, and other content to build an audience.
The competition in this market is intense, and not all ventures have succeeded, even when backed by tech giants. For example, Google had to shut down its Google+ platform in 2019 after eight years of operation.

COOPERATION BETWEEN SERBIAN AND CHINESE ASTRONOMERS

Laboratory, Lunar station, satellite...

The Memorandum of Understanding in the field of science, particularly in space research, signed with China during President Xi Jinping's visit to Serbia this year, is beginning to take shape in terms of cooperation. This was confirmed by the visit of a delegation from the People's Republic of China this autumn to the Astronomical Observatory, led by Prof. Dr. Luka Č.
During this trip, our delegation also stopped in Huangshan and Beijing, participating in various events related to space science. In Huangshan, representatives from the Astronomical Observatory attended the Second International Conference on Deep Space Research, part of the Tiandu Forum. Professor Popović was one of the few participants invited to give a lecture on "The Role of Quasars (Black Holes) in Deep Space Research." The conference was organized by the Deep Space Experiment Laboratory (DSEL), with which we signed a memorandum of cooperation regarding experiments on the Moon.

ASTROPHYSICS

Massive binary star systems

The dynamic development of astrophysical research at the Belgrade Astronomical Observatory, as noted by one of its chroniclers, began in the mid-20th century with the formal establishment of the Astrophysical Group in 1960, which included V. Oskanian, A. Kubicela, and J. Arsenijević. Over time, this group has expanded, and interest in scientific topics within this field has significantly increased.
Currently, key areas of focus include the astrophysics of stars and the Sun, astrophysical spectroscopy, and the study of stellar and galactic systems. The discovery of gravitational waves has led to the emergence of a new scientific branch known as gravitational or multi-stream astrophysics.
The Observatory is advancing in this new field through the MOBY project, which models the evolution of binary star systems as sources of gravitational waves. This project is led by astrophysicist Dr Jelena Petrović and is supported by the Science Foundation of the Ministry of Science, Technological Development, and Innovation of the Republic of Serbia through the Prism program. The concept for the MOBY project was inspired by Dr. Petrović's professional and scientific experiences from her work with institutes and collaborations in the Netherlands and Belgium.

TESLA

Great Scientist in Court Cases

Over its more than 70 years of existence, the Nikola Tesla Museum has published a significant number of important works that cover key periods of Nikola Tesla's life and inventive career. The museum houses Tesla's rich personal legacy, which includes tens of thousands of studies and handwritten notes from the brilliant physicist, engineer, and inventor, as well as numerous original photographs and photographic plates. These materials have served as a vital source for all publications to date, along with correspondence with leading scientists worldwide, friends, and family, a vast collection of press clippings, and various professional journals and books from his library.
However, there is one particularly valuable source that has yet to be published, which will offer future researchers a new perspective on Tesla's work. These are the records from court cases in which Tesla provided precise and detailed explanations of the various methods and devices he constructed for his laboratory research. Recognizing the immense value of these depositions, the Nikola Tesla Museum has launched a new publication titled "Tesla's Depositions in Court Cases." The publication begins with two cases: National Electric Signaling Company v. Atlantic Communication Company, where Tesla served as a defendant witness, and a case in which Tesla sued inventor Stead A. Asquith for infringing on his patent for a "speed indicator."

POLAR DAWN AND
INSPIRATION4 MISSIONS

Private for new space purposes

The first manned space flights and the first journeys around the Earth significantly altered human consciousness. These missions not only showcased the power of science and technology but also expanded humanity's living space beyond our planet.
Yuri Gagarin's historic flight in 1961 aboard the "Vostok-1" capsule lasted just 108 minutes and reached a maximum altitude of 327 km from Earth. This achievement stirred emotions across the globe. In the following years, flight durations and distances continued to increase. For instance, German Titov completed 16 orbits around the Earth in just 24 hours.
The United States entered the space race with the launch of the Mercury capsule carrying astronaut John Glenn, marking a pivotal moment in the competition between the USSR and the U.S. Another groundbreaking event was Alexei Leonov's first spacewalk from the "Voskhod-2" capsule, which was later mirrored by astronaut Edward White during the Gemini 4 mission.
Further advancements occurred with the Gemini spacecraft, which were linked to the Aegina rocket. In 1966, Gemini 11, with astronauts Conrad and Gordon, achieved a remarkable distance of 1,374 km from Earth. This was soon followed by the Apollo missions, which successfully reached the Moon and traveled over 400,000 km from Earth.
Ultimately, the earlier rivalry between the USSR and the USA transformed into collaboration with the establishment of the International Space Station (ISS). Scientific research became the focus, and setting new space records was no longer the primary goal.

UNIVERSE

Cleaning up a congested orbit

Orbital space debris, which includes a large accumulation of non-functioning satellites, discarded launch vehicles, and numerous small metal fragments from collisions of larger debris, poses a potential problem for the safe transportation of aircraft and satellites both within Earth’s orbit and in deep space. In recent years, startups and major space agencies have been working on ways to remove this debris and prevent a scenario in which humanity would be confined to Earth due to a dense belt of metal debris in orbit. The history of artificial objects entering orbit likely began with nuclear tests in the late 1950s. During these tests, significant amounts of material from the Earth's surface, including the famous metal cap, were inadvertently ejected by the force of the nuclear explosions, and some of this material likely reached orbit. The first artificial satellite, Sputnik 1, was launched in October 1957. It orbited Earth 1,440 times before burning up upon re-entry in January 1958. In the following decades, many satellites were launched, beginning with military projects and later transitioning to commercial ones. The United States launched its first satellite shortly after the Soviet Union's, and by 1961, there were 115 satellites already in orbit. Canada and Australia, with U.S. assistance, launched their first satellites, and France and Italy followed suit in the mid-1960s. By the end of the 20th century, the number of countries capable of launching satellites had increased to double digits, enabling a range of commercial satellites for television, telephone, internet signals, navigation, and various forms of surveillance. More recently, nanosatellites, which are roughly the size of a small home computer, have emerged, adding further challenges and potential future waste. Some of these satellites are in geostationary orbit at an altitude of about 36,000 km, while others are in low Earth orbit.

MEDICINE

Microorganisms We Depend On

Viruses are not only pathogenic; they can also act similarly to beneficial symbiotic bacteria, having a significant positive impact on human health. The immense importance of the microbiome—the diverse collection of bacteria and fungi that inhabit the human body—is widely recognized for its role in human life and the overall health of the planet. Additionally, scientific understanding of these microbial communities, which inhabit virtually all environments and play a central role in human health (and disease) as well as the biogeochemical processes of life on Earth, is considered a groundbreaking achievement in biological sciences.
A healthy microbiome is a vital part of human physiology, acting synergistically within the body and affecting every organ system. It aids in the breakdown, absorption, and assimilation of essential nutrients from food; influences metabolism—thereby impacting the risk of obesity and diabetes; plays a crucial role in regulating the immune system and preventing infections; and modulates inflammation, which may reduce the risk of chronic inflammatory diseases. Additionally, it affects skin function and may influence conditions such as eczema and acne. Notably, the microbiome can also impact mental health by influencing brain function and mood.
Less well known, however, is the equally essential part of this complex microbial community: the virome, a collection of various viruses that also inhabit the human body and the planet.

EVOLUTION

Homo sapiens vs. everyone

All people on this planet, from the Arctic in the north to Antarctica in the south, and from America in the west to Japan in the east, belong to a single species: Homo sapiens. Although we are often categorized into races - white, black, and yellow - this does not change the fact that we are fundamentally the same. We can mate with each other and produce fertile offspring, which is the defining characteristic of any species. Throughout history, we have come to understand our nature; we have often been more warlike than peace-loving, more materialistic than spiritually focused, and more inclined to seek an easy life than to engage in hard but rewarding work.
According to scientific research, Homo sapiens originated in East Africa and migrated to the Arabian Peninsula approximately 70,000 years ago. As our ancestors journeyed across these vast expanses, they would have noticed that much of Eurasia was already inhabited by other hominid species. This raises the question: why are we the only species that now rules the planet? What happened to the others? While there are several scientific theories explaining this phenomenon, two stand out most prominently.