Everything, be it living or non-living, has a lifespan. Even it goes right for planets, asteroids, and stars. NASA’s Hubble Telescope has captured an aging star’s images – Stingray nebula (also known as nebula Hen 3-1357). The images show that for the last two decades, the nebula is fading away. Such events are strange, as, in the universe, it takes to complete more than millions of years to complete a process. There is a drastic change observed in the level of brightness of the nebula.
About Hubble Telescope
Named after the famous astronomer Edwin Hubble, NASA (in association with European Space Agency) launched the Hubble Telescope in 1990 and is still in operation. It is one of the most remarkable observatories of our time, along with the Spitzer Space Telescope, Compton Gamma Ray Observatory, and the Chandra X-ray Observatory. The telescope has a 2.4-meter (7.9 ft) Cassegrain mirror of Ritchey–Chrétien design and four main instruments that observe the electromagnetic spectrum in the ultraviolet, visible, and near-infrared regions. The orbit (Low-Earth orbit) at which the telescope is placed allows it to capture extremely high-resolution images with substantially lower background light. The Hubble telescope’s primary computers are the 1.25 MHz DF-224 systems, containing three redundant CPUs and two redundant NSSC-1 (NASA Standard Spacecraft Computer, Model 1) using diode–transistor logic (DTL). It has done more than 1.3 million observations since its mission began in 1990.
Instruments in Hubble Telescope
High-speed photometer
Near-infrared camera and multi-object spectrometer (NICMOS)
Space telescope imaging spectrograph
Wide-field and planetary camera
Cosmic origins spectrograph (COS)
Corrective optics space telescope axial replacement (COSTAR)
Faint object camera
Faint object spectrograph
Fine guidance sensor
Achievements of Hubble Space Telescope
Determining the age of the universe.
Understanding the formation of planets.
Discovery of the first organic molecule on a planet outside our solar system.
Discovery of the four Plutonian moons.
Detecting a distant supernova suggesting that the universe only recently began speeding up.
About Stingray Nebula
It is the youngest planetary known nebula and situated in the southern constellation Ara (the Altar). Though the Stingray nebula’s size is 130 times the solar system’s size, it is merely one-tenth of the other nebulae’s dimensions. The reason behind the name is its shape, similar to a stingray fish. It has become ionized only in recent times. The mass-loss from the central star of the nebulas has ceased within the past few years. Stingray Nebula’s central star has become hotter and fainter as per the expectations when the star would become a DA white dwarf.
What can one depict from the recent images?
The real-time observation of the nebula in recent times is showing huge variations. There is a complete change in the shape and brightness of the Stingray nebula. Some of the observations regarding the nebula are:
The disappearance of bright blue fluorescent tendrils and filaments of gas (oxygen) toward the nebula center.
The absence of wavy edges from the nebula.
Stingray nebula no longer pops against the black velvet background of the universe.
Massive drop in temperature of the nebula.
One of the major causes that scientists estimate is the central star of the nebula, SAO 244567. Due to SAO 244567, the Stingray nebula is expanding. This expansion, along with temperature drop, in turn, is resulting in less ionizing radiation. Even the temperature drop is unique as observed between the years 1971 and 2002. At that time, the temperature at the nebula is nine times hotter than the Sun’s surface. Scientists affirmed that the temperature jump was a flash of helium fusion in a shell around the central star’s core.
Conclusion
In twenty years, the Stingray nebula has shown drastic changes. Some scientists say to stay cautious, and any consolidated inference can only come out after seeing more data in the future. Researchers estimate that the nebula will be undetectable in the next 20 or 30 years with the present fading rate.
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