Data Sonification: NASA | 25 Sep 2020
Why in News
The National Aeronautics and Space Administration’s (NASA) Chandra X-Ray Center (CXC) has unveiled a new ‘sonification’ project that transforms data from astronomical images into audio.
Key Points
- Data Sonification:
- It refers to the use of sound values to represent real data.
- It is the auditory version of data visualisation.
- In NASA’s Chandra (sonification) project, for instance, data is represented using a number of musical notes.
- The birth of a star, a cloud of dust or even a black hole can be ‘heard’ as a high- or low-pitched sound.
- Process of images into sound translation:
- Telescopes in space collect digital data, in the form of ones and zeroes (binary), before converting them into images.
- The images are visual representations of light and radiation of different wavelengths in space, that can’t be seen by the human eye.
- The Chandra project has created a celestial concert by translating the same data into sound. Pitch and volume are used to denote the brightness and position of a celestial object or phenomenon.
- Pitch is related to frequency of sound waves. Changing the number of vibrations per second changes the pitch.
- Volume, or loudness, is related to the strength, intensity, pressure, or power of the sound. Bigger/amplified vibrations result in bigger/louder sounds.
- The data has been collected by NASA’s Chandra X-Ray Observatory, Hubble Space Telescope and Spitzer Space Telescope.
- Thus far, Project Chandra has released three examples - the Galactic Centre, Cassiopeia A, and Pillars of Creation Nebula.
- The Galactic Centre
- It is the rotational centre of the Milky Way galaxy.
- It comprises a collection of celestial objects —
- Neutron and white dwarf stars,
- Clouds of dust and gas,
- A supermassive black hole called Sagittarius A*(weighs four million times the mass of the sun).
- Cassiopeia A
- Located around 11,000 light years away from Earth in the northern Cassiopeia constellation.
- Cassiopeia A is a well-known remnant of a once-massive star that was destroyed by a supernova explosion around 325 years ago.
- The Pillars of Creation
- The iconic Pillars of Creation is located in the centre of the Eagle Nebula (it is a constellation of stars), which is also known as Messier 16.
- Significance of Data Sonification:
- The sonification project was led by the Chandra X-ray Center in collaboration with NASA’s Universe of Learning Program (UoL), which aims to “incorporate NASA science content into the learning environment effectively and efficiently for learners of all ages”.
- Over the years, NASA has been working towards making data about space accessible for a larger audience.
- Sonification projects like this allow audiences - including visually-impaired communities - to experience space through data.
Chandra X-ray Project
- The Chandra X-ray Observatory was launched by Space Shuttle Columbia in 1999.
- The Chandra X-ray Observatory is part of NASA's fleet of "Great Observatories" along with the Hubble Space Telescope, the Spitzer Space Telescope.
- The "X-ray universe" refers to the universe as observed with telescopes designed to detect X-rays. X-rays are produced in the cosmos when matter is heated to millions of degrees. Such temperatures occur where high magnetic fields, or extreme gravity, or explosive forces exist in space.
- The telescope is named after the Nobel Prize-winning Indian astrophysicist Subrahmanyan Chandrasekhar.
- Subrahmanyan Chandrasekhar 's work implied that stars more massive than the so-called Chandrasekhar limit would eventually collapse to become objects so dense that not even light could escape it.
- Chandrasekhar limit is the theoretical maximum mass a white dwarf star can have and still remain a white dwarf.
- Although this finding was received with some skepticism at the time, it went on to form the foundation of the theory of black holes, eventually earning him a Nobel Prize in physics for 1983.
- Subrahmanyan Chandrasekhar 's work implied that stars more massive than the so-called Chandrasekhar limit would eventually collapse to become objects so dense that not even light could escape it.
The Hubble Space Telescope
- It is one of the largest and most versatile telescopes in service.
- It is a space telescope that was launched into low Earth orbit (540km above Earth) in 1990.
- Hubble’s four main instruments observe in the near ultraviolet, visible, and near infrared spectra.
Black Holes
- The term ‘black hole’ was coined in the mid-1960s by American Physicist John Archibald Wheeler.
- It refers to a point in space where the matter is so compressed as to create a gravity field from which even light cannot escape.
- Black-holes were theorized by Albert Einstein in 1915.
Supernova
- A supernova is the explosion of a star. It is the largest explosion that takes place in space.
- A supernova happens where there is a change in the core, or centre, of a star.
Neutron stars
- Neutron stars comprise one of the possible evolutionary end-points of high mass stars.
- Once the core of the star has completely burned to iron, energy production stops and the core rapidly collapses, squeezing electrons and protons together to form neutrons and neutrinos.
- A star supported by neutron degeneracy pressure is known as a ‘neutron star’, which may be seen as a pulsar if its magnetic field is favourably aligned with its spin axis.