NGC 1514, also known as the Crystal Ball Nebula, is a

planetary nebula A planetary nebula is a type of emission nebula consisting of an expanding, glowing shell of ionized gas ejected from red giant stars late in their lives. The term "planetary nebula" is a misnomer because they are unrelated to planets. The ...

in the

zodiac The zodiac is a belt-shaped region of the sky that extends approximately 8° north and south celestial latitude of the ecliptic – the apparent path of the Sun across the celestial sphere over the course of the year. Within this zodiac ...

constellation A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object. The first constellati ...

Taurus Taurus is Latin for 'bull' and may refer to: * Taurus (astrology), the astrological sign ** Vṛṣabha, in vedic astrology * Taurus (constellation), one of the constellations of the zodiac * Taurus (mythology), one of two Greek mythological ch ...

, positioned to the north of the star

Psi Tauri Psi Tauri, which is Latinized from ψ Tauri, is a solitary star in the zodiac constellation of Taurus. It has a yellow-white hue and is visible to the naked eye with an apparent visual magnitude of +5.22. The distance to this system, as d ...

along the constellation border with

Perseus In Greek mythology, Perseus (, ; Greek language, Greek: Περσεύς, Romanization of Greek, translit. Perseús) is the legendary founder of the Perseid dynasty. He was, alongside Cadmus and Bellerophon, the greatest Greek hero and slayer of ...

. Distance to the nebula is 455 pc, according to its

Gaia In Greek mythology, Gaia (; , a poetic form of ('), meaning 'land' or 'earth'),, , . also spelled Gaea (), is the personification of Earth. Gaia is the ancestral mother—sometimes parthenogenic—of all life. She is the mother of Uranus (S ...

DR3 parallax. It was discovered by

William Herschel Frederick William Herschel ( ; ; 15 November 1738 – 25 August 1822) was a German-British astronomer and composer. He frequently collaborated with his younger sister and fellow astronomer Caroline Herschel. Born in the Electorate of Hanover ...

on November 13, 1790, describing it as "a most singular phenomenon" and forcing him to rethink his ideas on the construction of the heavens. Up until this point Herschel was convinced that all nebulae consisted of masses of stars too remote to resolve, but now here was a single star "surrounded with a faintly luminous atmosphere". He concluded: "Our judgement I may venture to say, will be, that the nebulosity about the star is not of a starry nature." This is a double-shell nebula that is described as, "a bright roundish amorphous PN" with a radius of around and a faint halo that has a radius of . It consists of an outer shell, an inner shell, and bright blobs. The inner shell appears to be distorted, but was likely originally spherical. An alternative description is of "lumpy nebula composed of numerous small bubbles" with a somewhat filamentary structure in the outer shell.

Infrared Infrared (IR; sometimes called infrared light) is electromagnetic radiation (EMR) with wavelengths longer than that of visible light but shorter than microwaves. The infrared spectral band begins with the waves that are just longer than those ...

observations show a huge region of dust surrounds the planetary nebula, spanning . There is also a pair of rings forming what appears to be a

diabolo The diabolo ( ; commonly misspelled ''diablo'') is a juggling or circus skills, circus juggling prop, prop consisting of an axle () and two cone, cups (hourglass/egg timer shaped) or cylinder, discs derived from the Chinese yo-yo. This object i ...

-like structure, similar to those found in MyCn 18, but these are extremely faint and only visible in the mid-infrared. Observations by the

James Webb Space Telescope The James Webb Space Telescope (JWST) is a space telescope designed to conduct infrared astronomy. As the largest telescope in space, it is equipped with high-resolution and high-sensitivity instruments, allowing it to view objects too old, Lis ...

shows filamentary and clumpy details in the rings. It is suggested the material from which the rings were formed was ejected during an early period of very heavy mass loss from the planetary nebula progenitor, then shaped by asymmetrical fast winds from the central binary pair. The combined mass of the gas and dust is estimated at The ionized gas is moderately excited, and the electron temperature is estimated to be 15,000 K. The nebula originated from a

binary star A binary star or binary star system is a system of two stars that are gravitationally bound to and in orbit around each other. Binary stars in the night sky that are seen as a single object to the naked eye are often resolved as separate stars us ...

system with the designation HD 281679 from the ''Henry Draper Catalogue''. The bright, visible component is a

giant star A giant star has a substantially larger radius and luminosity than a main-sequence (or ''dwarf'') star of the same surface temperature. They lie above the main sequence (luminosity class V in the Yerkes spectral classification) on the Hertzsp ...

on the

horizontal branch The horizontal branch (HB) is a stage of stellar evolution that immediately follows the red-giant branch in stars whose masses are similar to the Sun's. Horizontal-branch stars are powered by helium fusion in the core (via the triple-alpha proc ...

with a

stellar classification In astronomy, stellar classification is the classification of stars based on their stellar spectrum, spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a Prism (optics), prism or diffraction gratin ...

of A0III, while the nebula-generating companion is now a hot, sub-luminous

O-type star An O-type star is a hot, blue star of spectral type O in the Yerkes classification system employed by astronomers. They have surface temperatures in excess of 30,000 kelvins (K). Stars of this type have strong absorption lines of ionised h ...

. The two were originally thought to have an orbital period on the order of 10 days, but observations of the system over years showed that their orbit is actually one of the longest known for any planetary nebula, with a period of about 9 years. Their

orbital eccentricity In astrodynamics, the orbital eccentricity of an astronomical object is a dimensionless parameter that determines the amount by which its orbit around another body deviates from a perfect circle. A value of 0 is a circular orbit, values be ...

is about 0.5.

References

External links

Basic data on NGC 1514

{{sky, 04, 09, 16.984, +, 30, 46, 33.47, 600 Planetary nebulae

1514 Year 1514 ( MDXIV) was a common year starting on Sunday of the Julian calendar. Events January–March * January 10 – A great fire breaks out, in the Rialto of Venice. * February 12 – War of the League of Cambrai: In ...

Taurus (constellation) Discoveries by William Herschel 17901119