Quasar Spotted in the Milky Way!

The James Webb Space Telescope has captured a stunning image of the cosmos, revealing nearby stars in the Milky Way and distant galaxies. Among these celestial objects, quasars stand out as exceptionally bright sources, visible from billions of light years away. These are powered by supermassive black holes at the centers of galaxies. Interestingly, the Milky Way hosts 'microquasars,' smaller versions of quasars that form around ordinary black holes. The first microquasar, SS 433, was discovered in 1979 and consists of a type-A supergiant and a stellar-mass black hole. Recent studies using gamma rays have shed light on the acceleration of electrons in the jets of SS 433, suggesting a process called diffusive shock acceleration. Microquasars provide valuable insights into the workings of quasars and the extreme physics near black holes.

Takeaways

• 🌌 The James Webb Space Telescope captured an image showing nearby stars in the Milky Way and distant galaxies.
• 🌟 Quasars are extremely bright objects that can be seen from billions of light years away, standing out from the stars in their host galaxies.
• ✨ Scientists have discovered that microquasars, smaller versions of quasars, can exist within our own Milky Way galaxy.
• 🔭 Astronomers began mapping the universe in radio waves in the 1950s, leading to the discovery of quasars which emit strong radio signals.
• 🖇️ Quasars are associated with supermassive black holes, which can be millions or billions of times the mass of the Sun and are often found at the centers of galaxies.
• ⚫️ The center of the Milky Way, Sagittarius A*, is a supermassive black hole but is not active enough to be considered a quasar.
• 💫 Microquasars form around ordinary black holes when a nearby star gets sucked into its gravitational pull, creating a smaller, less intense version of a quasar.
• 🛰️ The first microquasar, SS 433, was discovered in 1979 and has been extensively studied to understand the properties and dynamics of quasars.
• ⚡ The outer jets of SS 433 emit gamma rays, which are thought to be produced by high-energy electrons through inverse Compton scattering.
• 🚀 High-energy electrons in the jets of SS 433 are believed to be accelerated to near the speed of light due to diffusive shock acceleration caused by magnetic fields.
• 🌟 Microquasars in the Milky Way provide valuable insights into the workings of massive quasars at the centers of distant galaxies.

Q & A

What is the primary subject of the video script?

The primary subject of the video script is the discovery and explanation of quasars, specifically microquasars, within our own Milky Way galaxy.

What is the James Webb Space Telescope's role in the script?

The James Webb Space Telescope is mentioned as the instrument that captured the beautiful image discussed in the script, which includes nearby stars and distant galaxies.

What are the two types of objects visible in the image from the James Webb Space Telescope?

The two types of objects visible are the nearby stars within our Milky Way galaxy, which appear as points of light with diffraction spikes, and the more distant galaxies that appear as smeared out elliptical or spiral blurs.

What is a quasar and why is it significant?

A quasar is an extremely bright and distant object, powered by a supermassive black hole actively accreting matter. It is significant because it is one of the brightest objects in the universe and can be observed from billions of light years away.

What is a microquasar and how does it differ from a regular quasar?

A microquasar is a smaller, less powerful version of a quasar, formed around ordinary black holes that are a few times more massive than the Sun. It differs from a regular quasar, which is powered by supermassive black holes at the centers of galaxies.

How did astronomers initially discover quasars?

Astronomers initially discovered quasars in the 1950s by mapping the universe in radio waves and finding bright radio sources that were not visible in the optical spectrum.

What is the name of the first microquasar discovered and in what year?

The first microquasar discovered was named SS 433, and it was documented in 1979.

How do microquasars help scientists understand quasars?

Microquasars, being closer to Earth, allow scientists to study the properties and dynamics of both microquasars and their larger counterparts in more detail, providing insights into the inner workings of massive quasars in distant galaxies.

What is the process called that is believed to be responsible for the acceleration of electrons in the jets of SS 433?

The process believed to be responsible for the acceleration of electrons in the jets of SS 433 is called diffusive shock acceleration.

What is the role of gamma rays in understanding the outer jets of SS 433?

Gamma rays emitted by SS 433 provide clues about the energy of the electrons in the jets, supporting the inverse Compton scattering theory and helping scientists understand the dynamics and energy transfer within the jets.

What is the significance of the HESS collaboration's findings on SS 433?

The HESS collaboration's findings on SS 433 are significant because they provide evidence supporting the inverse Compton scattering theory and shed light on the acceleration of electrons to high energies, which is crucial for understanding the production of high-energy gamma rays.

Outlines

00:00

🌌 Introduction to Quasars and Microquasars

The video script begins with an introduction to the James Webb Space Telescope's stunning image of the cosmos, highlighting the contrast between nearby stars of our Milky Way and distant galaxies. It introduces the concept of quasars, which are incredibly bright objects visible from billions of light years away, and teases the idea of microquasars hidden within our own galaxy. The script then delves into the history of astronomy and the discovery of radio waves in the universe, leading to the identification of quasars as quasi-stellar radio sources. It explains that quasars are associated with supermassive black holes and their accretion disks, which emit enormous amounts of energy. The video promises to explore how scientists have used microquasars to understand quasars throughout the universe.

05:02

🌟 The Mystery and Discovery of Quasars

This paragraph discusses the initial observations of quasars as points of light that were brighter than any star but smaller than galaxies. It explains that these objects were later understood to be powered by supermassive black holes at the centers of galaxies. The script describes the process by which matter spirals into the black hole, emitting light and sometimes producing relativistic jets. The paragraph also touches on the Milky Way's own supermassive black hole, Sagittarius A*, which is currently not active enough to be considered a quasar. It then introduces the concept of microquasars, which are similar phenomena but occur around ordinary black holes, and mentions the first microquasar discovered, SS 433.

10:06

🚀 Studying Microquasars to Understand Quasars

The script continues by detailing the study of microquasars, specifically SS 433, to gain insights into the behavior of quasars. It explains the structure of SS 433, which consists of a type-A supergiant star and a stellar-mass black hole in a binary system. The paragraph describes the two types of jets emitted by SS 433 and the mystery surrounding their formation and termination. The script then discusses a recent study that suggests the presence of high-energy photons, or gamma rays, being emitted by the outer jets of SS 433, hinting at a process known as inverse Compton scattering as the source of these gamma rays.

15:10

🌕 The Role of Microquasars in Astronomical Research

The final paragraph emphasizes the importance of microquasars in understanding the processes occurring in quasars across the universe. It describes how the study of SS 433's outer jets and the high-energy gamma rays they emit can provide valuable information about the behavior of electrons and the acceleration processes within these jets. The script also discusses the phenomenon of diffusive shock acceleration, which may explain the extreme energies of electrons in the jets. The paragraph concludes by highlighting the potential of microquasars as beacons in the sky, offering astronomers a wealth of information about the cosmos.

Keywords

Quasar

A quasar is an extremely bright and distant celestial object, which is powered by a supermassive black hole at the center of a galaxy. They are among the most luminous objects in the universe and emit vast amounts of energy, primarily due to the accretion of matter onto the black hole and the subsequent ejection of this matter in the form of relativistic jets. In the video, the concept of quasars is central as it discusses how these objects, though incredibly bright, can be found within our own Milky Way in the form of microquasars.

James Webb Space Telescope

The James Webb Space Telescope (JWST) is a large, space-based observatory that is considered the successor to the Hubble Space Telescope. It is designed to capture images of the universe in the infrared spectrum, allowing for the observation of objects that are too distant or faint for visible light telescopes. In the video, the JWST is credited with capturing the image that introduces the topic of quasars and the various celestial objects discussed.

Milky Way

The Milky Way is the galaxy that contains our Solar System, consisting of billions of stars, planets, and other celestial bodies. It is a spiral galaxy, and its structure is highlighted in the video when discussing the difference between nearby stars and distant galaxies. The video also mentions the presence of microquasars within the Milky Way, which are analogous to quasars but on a smaller scale.

Microquasar

A microquasar is a type of celestial object that is similar to a quasar but is formed around a smaller, stellar-mass black hole rather than a supermassive one. These objects can be found in binary star systems and emit jets of matter, similar to quasars, but on a smaller scale. The video discusses microquasars as a way to study the properties of quasars without having to look at distant galaxies, as they are closer and more easily observed.

Supermassive Black Hole

A supermassive black hole is a black hole with a mass that is millions or even billions of times greater than that of our Sun. These black holes are typically found at the centers of galaxies, including the Milky Way, where they play a significant role in the dynamics and evolution of the galaxy. The video explains that quasars are associated with supermassive black holes and their accretion disks, which are responsible for the immense luminosity of quasars.

Accretion Disk

An accretion disk is a structure formed by matter that is spiraling inwards towards a massive object, such as a black hole. The matter in the disk is heated due to friction, causing it to emit radiation, including visible light and radio waves. In the context of the video, the accretion disk around a black hole is the source of the intense light emitted by quasars.

Relativistic Jets

Relativistic jets are high-speed outflows of matter that are ejected from the vicinity of a black hole. These jets move at speeds close to the speed of light and are a key feature of quasars and microquasars. The video describes how these jets are produced by the interaction of the black hole's magnetic field with the surrounding matter and how they emit radio signals as they propagate through the universe.

Cosmic Rays

Cosmic rays are high-energy particles, mainly protons and atomic nuclei, that originate from outer space and travel through the universe at nearly the speed of light. In the video, it is mentioned that the particles in the jets of quasars can propagate as cosmic rays, influenced by intergalactic magnetic fields.

Sagittarius A*

Sagittarius A* (pronounced 'A-star') is the supermassive black hole located at the center of the Milky Way galaxy. It is not considered a quasar because its accretion disk is too thin and faint. The video contrasts Sagittarius A* with the more active quasars found in other galaxies, noting that a quasar of that nature close to Earth could be harmful to life.

SS 433

SS 433 is the first discovered microquasar and is a binary star system consisting of a type-A supergiant star and a stellar-mass black hole. The black hole accretes material from the star, producing jets that emit light at various wavelengths. The video discusses SS 433 as an important object for studying the properties of microquasars and, by extension, quasars.

Inverse Compton Scattering

Inverse Compton scattering is a process in which a low-energy photon collides with a high-energy electron, transferring energy to the photon and boosting its frequency. This process is mentioned in the video as a mechanism that could explain the emission of gamma rays from the outer jets of SS 433.

Diffusive Shock Acceleration

Diffusive shock acceleration is a mechanism by which particles can gain energy by repeatedly crossing a shock front, similar to how a vehicle might gain speed by driving over a series of speed bumps. In the context of the video, this process is proposed to explain how electrons in the jets of SS 433 reach extremely high speeds and energies, resulting in the production of high-energy gamma rays.

Highlights

The James Webb Space Telescope captures an image showing nearby stars and distant galaxies.

Quasars are extremely bright objects visible from billions of light years away.

Microquasars are tiny versions of quasars that can be found within our own Milky Way.

Astronomers used radio waves to map the universe, leading to the discovery of quasars.

Quasars are quasi-stellar radio sources that emit a lot of radio waves but are not stars.

Supermassive black holes at the centers of galaxies are associated with quasars.

Quasars outshine hundreds of billions of stars in their host galaxies.

The Milky Way's supermassive black hole, Sagittarius A*, is not active enough to be a quasar.

Microquasars are formed around ordinary black holes and can be studied more easily due to their proximity.

SS 433 is the first microquasar discovered, consisting of a type-A supergiant and a stellar-mass black hole.

SS 433 emits two types of jets with different properties and extents.

Gamma rays from SS 433's outer jets are produced through inverse Compton scattering.

Electrons in SS 433's jets are accelerated to extremely high energies.

Diffusive shock acceleration is the process responsible for the high-energy electrons in SS 433's jets.

Microquasars in the Milky Way provide insights into the workings of massive quasars in distant galaxies.

The video discusses the potential dangers of a close quasar to Earth and the unique opportunity to study microquasars.