SN 1572 (Tycho's Supernova, Tycho's Nova), or B Cassiopeiae (B Cas), was a supernova of Type Ia in the constellation Cassiopeia, one of eight supernovae visible to the naked eye in historical records. It appeared in early November 1572 and was independently discovered by many individuals.
The remnant of the supernova has been observed optically but was first detected at radio wavelengths; it is often known as 3C 10, a radio-source designation, although increasingly as Tycho's supernova remnant.
|Other designations||SN 1572, HR 92, SN 1572A, SNR G120.1+01.4, SNR G120.2+01.4, 1ES 0022+63.8, 1RXS J002509.2+640946, V* B Cas, BD+63 39a, 8C 0022+638, 4C 63.01, 3C 10, 3C 10.0, 2C 34|
|Spectral class||Type Ia|
|Right ascension||0h 25.3m|
|Distance||between 8,000 ly (2.5 kpc) and 9,800 ly (3.0 kpc)|
|Peak apparent magnitude||−4|
|Preceded by||SN 1181|
|Followed by||SN 1604|
The appearance of the Milky Way supernova of 1572 belongs among the more important observation events in the history of astronomy. The appearance of the "new star" helped to revise ancient models of the heavens and to speed on a revolution in astronomy that began with the realisation of the need to produce better astrometric star catalogues (and thus the need for more precise astronomical observing instruments). It also challenged the Aristotelian dogma of the unchangeability of the realm of stars.
The supernova of 1572 is often called "Tycho's supernova", because of Tycho Brahe's extensive work De nova et nullius aevi memoria prius visa stella ("Concerning the Star, new and never before seen in the life or memory of anyone", published in 1573 with reprints overseen by Johannes Kepler in 1602, and 1610), a work containing both Tycho Brahe's own observations and the analysis of sightings from many other observers. Tycho was not the first to observe the 1572 supernova, although he was probably the most accurate observer of the object. Almost as accurate were his European colleagues, such as Wolfgang Schuler, Thomas Digges, John Dee, Francesco Maurolico, Jerónimo Muñoz, Tadeáš Hájek, or Bartholomäus Reisacher.
In England, Queen Elizabeth had the mathematician and astrologer Thomas Allen, come and visit "to have his advice about the new Star that appeared in the Cassiopeia to which he gave his Judgement very learnedly", as the antiquary John Aubrey recorded in his memoranda a century later.
In Ming dynasty China, the star became an issue between Zhang Juzheng and the young Wanli Emperor: in accordance with the cosmological tradition, the emperor was warned to consider his misbehavior, since the new star was interpreted as an evil omen.
The more reliable contemporary reports state that the new star itself burst forth soon after November 2, and by November 11 it was already brighter than Jupiter. Around November 16, 1572, it reached its peak brightness at about magnitude −4.0, with some descriptions giving it as equal to Venus when that planet was at its brightest. The supernova remained visible to the naked eye into early 1574, gradually fading until it disappeared from view.
The supernova was classified as type I on the basis of its historical light curve soon after type I and type II supernovae were first defined on the basis of their spectra. The X-ray spectrum of the remnant showed that it was almost certainly of type Ia, but its exact classification continued to be debated until the detection of a light echo in 2008 gave final confirmation that it is a normal type Ia.
The classification as a type Ia supernova of normal luminosity allows an accurate measure of the distance to SN 1572. The peak absolute magnitude can be calculated from the B-band decline rate to be −19.0±0.3. Given estimates of the peak apparent magnitude and the known extinction of 1.86±0.2 magnitudes, the distance is 3.8+1.5
The distance to the supernova remnant has been estimated to between 2 and 5 kpc (approx. 6,500 and 16,300 light-years), with recent studies suggesting a narrower range of 2.5 and 3 kpc (approx. 8,000 and 9,800 light-years).
The search for a supernova remnant was negative until 1952, when Hanbury Brown and Cyril Hazard reported a radio detection at 158.5 MHz, obtained at the Jodrell Bank Observatory. This was confirmed, and its position more accurately measured in 1957 by Baldwin and Edge using the Cambridge Radio Telescope working at a wavelength of 1.9 m. The remnant was also identified tentatively in the second Cambridge Catalogue of Radio Sources as object "2C 34," and more firmly as "3C 10" in the third Cambridge list (Edge et al. 1959). There is no dispute that 3C 10 is the remnant of the supernova observed in 1572–1573. Following a 1964 review article by Minkowski, the designation 3C 10 appears to be that most commonly used in the literature when referring to the radio remnant of B Cas, although some authors use the tabulated Galactic designation G120.7+2.1 and many authors commonly refer to it as Tycho's supernova remnant. Because the radio remnant was reported before the optical supernova-remnant wisps were discovered, the designation 3C 10 is used by some to signify the remnant at all wavelengths.
An X-ray source designated Cepheus X-1 (or Cep X-1) was detected by the Uhuru X-ray observatory at 4U 0022+63. Earlier catalog designations are X120+2 and XRS 00224+638. Cepheus X-1 is actually in the constellation Cassiopeia, and it is SN 1572, the Tycho SNR.
The supernova remnant of B Cas was discovered in the 1960s by scientists with a Palomar Mountain telescope as a very faint nebula. It was later photographed by a telescope on the international ROSAT spacecraft. The supernova has been confirmed as Type Ia, in which a white dwarf star has accreted matter from a companion until it approaches the Chandrasekhar limit and explodes. This type of supernova does not typically create the spectacular nebula more typical of Type II supernovas, such as SN 1054 which created the Crab Nebula. A shell of gas is still expanding from its center at about 9,000 km/s. A recent study indicates a rate of expansion below 5,000 km/s.
In October 2004, a letter in Nature reported the discovery of a G2 star, similar in type to our own Sun and named Tycho G. It is thought to be the companion star that contributed mass to the white dwarf that ultimately resulted in the supernova. A subsequent study, published in March 2005, revealed further details about this star: Tycho G was probably a main-sequence star or subgiant before the explosion, but some of its mass was stripped away and its outer layers were shock-heated by the supernova. Tycho G's current velocity is perhaps the strongest evidence that it was the companion star to the white dwarf, as it is traveling at a rate of 136 km/s, which is more than four times faster than the mean velocity of other stars in its stellar neighbourhood. This find has been challenged in recent years. The star is relatively far away from the center and does not show rotation which might be expected of a companion star.
In Gaia DR2, the star was calculated to be 6400+2000
−1200 light-years away, on the lower end of SN 1572's possible range of distances, which in turn lowered the calculated velocity from 136 km/s to only 56 km/s.
In the ninth episode of James Joyce's Ulysses, Stephen Dedalus associates the appearance of the supernova with the youthful William Shakespeare, and in the November 1998 issue of Sky & Telescope, three researchers from Southwest Texas State University, Don Olson and Russell Doescher of the Physics Department and Marilynn Olson of the English Department, argued that this supernova is described in Shakespeare's Hamlet, specifically by Bernardo in Act I, Scene i.
The protagonist in Arthur C. Clarke's 1955 short story "The Star" casually mentions the supernova. It is a major element in Frederik Pohl's spoof science article, "The Martian Star-Gazers", first published in Galaxy Science Fiction Magazine in 1962.
Neil DeGrasse Tyson mentions this 1572 and the 1604 incidents in his 2017 book Astrophysics for People in a Hurry. He emphasizes that although these visuals were widely reported, no one saw the invisible x-rays or gamma rays.
Year 1572 (MDLXXII) was a leap year starting on Tuesday (link will display the full calendar) of the Julian calendar.1572 in science
The year 1572 in science and technology included many events, some of which are listed here.Bayer designation
A Bayer designation is a stellar designation in which a specific star is identified by a Greek or Latin letter followed by the genitive form of its parent constellation's Latin name. The original list of Bayer designations contained 1,564 stars.
Most of the brighter stars were assigned their first systematic names by the German astronomer Johann Bayer in 1603, in his star atlas Uranometria. Bayer assigned a lower-case Greek letter (alpha (α), beta (β), gamma (γ), etc.) or a Latin letter (A, b, c, etc.) to each star he catalogued, combined with the Latin name of the star's parent constellation in genitive (possessive) form. (See 88 modern constellations for the genitive forms.) For example, Aldebaran in the constellation Taurus (the Bull) is designated α Tauri (pronounced Alpha Tauri), which means "Alpha of the Bull".Bayer used Greek letters for the brighter stars, but the Greek alphabet has only twenty-four letters, while a single constellation may contain fifty or more stars visible to the naked eye. When the Greek letters ran out, Bayer continued with Latin letters: upper case A, followed by lower case b through z (omitting j and v), for a total of another 24 letters. Bayer never went beyond z, but later astronomers added more designations using both upper and lower case Latin letters, the upper case letters following the lower case ones in general. Examples include s Carinae (s of the constellation Carina), d Centauri (d of the constellation Centaurus), G Scorpii (G of the constellation Scorpius), and N Velorum (N of the constellation Vela). The last upper-case letter used in this way was Q.
Bayer catalogued only a few stars too far south to be seen from Germany, but later astronomers (notably Lacaille and Gould) supplemented Bayer's catalog with entries for southern constellations.Beta Cassiopeiae
Beta Cassiopeiae (β Cassiopeiae, abbreviated Beta Cas or β Cas), officially named Caph , is a Delta Scuti variable star in the constellation of Cassiopeia. It is a giant star belonging to the spectral class F2. The white star of second magnitude (+2.27 mag) has an absolute magnitude of +1.16 mag.Chi Cassiopeiae
Chi Cassiopeiae (χ Cassiopeiae) is a solitary, yellow-hued star in the constellation Cassiopeia. It is visible to the naked eye with an apparent visual magnitude of +4.7. Based upon an annual parallax shift of 15.67 mas as seen from Earth, this system is located roughly 208 light years from the Sun. At that distance, the visual magnitude is diminished by an extinction of 0.18 due to interstellar dust.With a stellar classification of G9 IIIb, it has the spectrum of an evolved, G-type giant star. It has an estimated age of a billion years and is a red clump star that it is generating energy through helium fusion at its core. The star has about double the mass of the Sun and has expanded to 11 times the Sun's radius. It is radiating 67.6 times the Sun's luminosity from its photosphere at an effective temperature of 4,746 K.De Stella Nova
De Stella Nova in Pede Serpentarii (On the New Star in the Foot of the Serpent Handler), generally known as De Stella Nova was a book written by Johannes Kepler between 1605 and 1606, when the book was published in Prague.Kepler wrote the book following the appearance of the supernova SN 1604, also known as Kepler's Supernova. This star appeared in the constellation Ophiuchus, the Greek (Ὀφιοῦχος Ophioukhos) "serpent-bearer" which is also known in Latin as Serpentarii.
The SN 1604 supernova was observable for almost a year, from October 1604 to October 1605. Observation conditions were good, particularly when it was first visible. A conjunction of Jupiter and Mars happened to be taking place near the place where the supernova appeared, meaning that astronomers happened to be looking in its direction. As a result there were many witnesses to its appearance, but Kepler's observations were particularly meticulous. The care he took not only to record his own observations but to compile the observations of other astronomers make De Stella Nova a very important record both of the supernova itself, and of the astronomy of the early 17th century.Kepler's Supernova
SN 1604, also known as Kepler's Supernova, Kepler's Nova or Kepler's Star, was a supernova of Type Ia that occurred in the Milky Way, in the constellation Ophiuchus. Appearing in 1604, it is the most recent supernova in our own galaxy to have been unquestionably observed by the naked eye, occurring no farther than 6 kiloparsecs or about 20,000 light-years from Earth.List of supernova remnants
This is a list of observed supernova remnants.List of supernovae
This is a list of supernovae that are of historical significance. These include supernovae that were observed prior to the availability of photography, and individual events that have been the subject of a scientific paper that contributed to supernova theory.Nu Cassiopeiae
Nu Cassiopeiae, Latinized from ν Cassiopeiae, is a solitary star in the northern constellation of Cassiopeia. With an apparent visual magnitude of +4.89, it is a faint star but visible to the naked eye. Based upon an annual parallax shift of 7.92 mas as seen from Earth, this star is located around 410 light years from the Sun. Cowley et al. (1969) catalogued this star with a stellar classification of B9 III, indicating it has the spectrum of an evolved B-type giant star. However, Palmer et al. (1968) assigned it a class of B8 V, which would instead suggest it is an ordinary B-type main-sequence star.Pilar Ruiz-Lapuente
Pilar Ruiz-Lapuente (born 1964, Barcelona) is an astrophysicist working as a professor at the University of Barcelona. Her work has included research on type Ia supernovae. In 2004, she led the team that searched for the companion star to the white dwarf that became supernova SN 1572, observed by Tycho Brahe, among others. Ruiz-Lapuente's research on supernovae contributed to the discovery of the accelerating expansion of the universe.Psi Cassiopeiae
Psi Cassiopeiae (ψ Cassiopeiae) is a binary star system in the northern constellation of Cassiopeia.
The primary component, ψ Cassiopeiae A, is an orange K-type giant with an apparent magnitude of +5.0; it is a double star, designated CCDM J01259+6808AB, with a fourteenth magnitude star (component B) located 3 arcseconds from the primary. Located about 25 arcseconds distant there is a 9.8 magnitude optical companion CCDM J01259+6808CD, designated ψ Cassiopeiae B in older star catalogues, which is itself another double; CD comprises a 9.4 magnitude component C and a 10 magnitude component D.SN 1181
First observed between August 4 and August 6, 1181, Chinese and Japanese astronomers recorded the supernova now known as SN 1181 in eight separate texts.
One of only eight supernovae in the Milky Way observable with the naked eye in recorded history, it appeared in the constellation Cassiopeia and was visible in the night sky for about 185 days.
The radio and X-ray pulsar J0205+6449 (also known as 3C 58), which rotates about 15 times per second, is possibly the remnant from this event. If the supernova and pulsar are associated, the star is still rotating about as quickly as it did when it first formed. This is in contrast to the Crab pulsar, known to be the remnant of the SN 1054 supernova in the year 1054, which has lost two-thirds of its rotational energy in essentially the same time span. Recent radio surveys of 3C 58, however, indicate that this supernova remnant may be much older and thus not associated with SN 1181.SN 185
SN 185 was a transient astronomical event observed in AD 185, likely a supernova. The transient occurred in the direction of Alpha Centauri, between the constellations Circinus and Centaurus, centered at RA 14h 43m Dec −62° 30′, in Circinus. This "guest star" was observed by Chinese astronomers in the Book of Later Han (后汉书), and might have been recorded in Roman literature. It remained visible in the night sky for eight months. This is believed to be the first supernova for which records exist.
The Book of Later Han gives the following description:
In the 2nd year of the epoch Zhongping [中平], the 10th month, on the day Kwei Hae [December 7], a strange star appeared in the middle of Nan Mun [asterism containing Alpha Centauri], It was like a large bamboo mat. It displayed various colors, both pleasing and otherwise. It gradually lessened. In the 6th month of the succeeding year it disappeared.
The gaseous shell RCW 86 is probably the supernova remnant of this event and has a relatively large angular size of roughly 45 arc minutes (larger than the apparent size of the full moon, which varies from 29 to 34 arc minutes). The distance to RCW 86 is estimated to be 2,800 parsecs (9,100 light-years). Recent X-ray studies show a good match for the expected age.Infrared observations from NASA's Spitzer Space Telescope and Wide-field Infrared Survey Explorer (WISE) reveal how the supernova occurred and how its shattered remains ultimately spread out to great distances. The findings show that the stellar explosion took place in a hollowed-out cavity, allowing material expelled by the star to travel much faster and farther than it would have otherwise.Differing modern interpretations of the Chinese records of the guest star have led to quite different suggestions for the astronomical mechanism behind the event, from a core-collapse supernova to a distant, slow-moving comet – with correspondingly wide-ranging estimates of its apparent visual magnitude (−8 to +4). The recent Chandra results suggest that it was most likely a Type Ia supernova (a type with consistent absolute magnitude), and therefore similar to Tycho's Supernova (SN 1572), which had apparent magnitude −4 at a similar distance.Supernova remnant
A supernova remnant (SNR) is the structure resulting from the explosion of a star in a supernova. The supernova remnant is bounded by an expanding shock wave, and consists of ejected material expanding from the explosion, and the interstellar material it sweeps up and shocks along the way.
There are two common routes to a supernova: either a massive star may run out of fuel, ceasing to generate fusion energy in its core, and collapsing inward under the force of its own gravity to form a neutron star or a black hole; or a white dwarf star may accrete material from a companion star until it reaches a critical mass and undergoes a thermonuclear explosion.
In either case, the resulting supernova explosion expels much or all of the stellar material with velocities as much as 10% the speed of light (or approximately 30,000 km/s). These ejecta are highly supersonic: assuming a typical temperature of the interstellar medium of 10,000 K, the Mach number can initially be > 1000. Therefore, a strong shock wave forms ahead of the ejecta, that heats the upstream plasma up to temperatures well above millions of K. The shock continuously slows down over time as it sweeps up the ambient medium, but it can expand over hundreds or thousands of years and over tens of parsecs before its speed falls below the local sound speed.
One of the best observed young supernova remnants was formed by SN 1987A, a supernova in the Large Magellanic Cloud that was observed in February 1987. Other well-known supernova remnants include the Crab Nebula; Tycho, the remnant of SN 1572, named after Tycho Brahe who recorded the brightness of its original explosion; and Kepler, the remnant of SN 1604, named after Johannes Kepler. The youngest known remnant in our galaxy is G1.9+0.3, discovered in the galactic center.Thomas Hood (mathematician)
Thomas Hood (1556–1620) was an English mathematician and physician, the first lecturer in mathematics appointed in England, a few years before the founding of Gresham College. He publicized the Copernican theory, and discussed the nova SN 1572. (Tycho's Nova). He also innovated in the design of mathematical and astronomical instruments.Timeline of white dwarfs, neutron stars, and supernovae
Timeline of neutron stars, pulsars, supernovae, and white dwarfs
Note that this list is mainly about the development of knowledge, but also about some supernovae taking place. For a separate list of the latter, see the article List of supernovae. All dates refer to when the supernova was observed on Earth or would have been observed on Earth had powerful enough telescopes existed at the time.Tycho G
Tycho G has been proposed as the surviving binary companion star of the SN 1572 supernova event. The star is located about 6400±1500 light-years away in the constellation Cassiopeia. It is a subgiant, similar to our Sun in temperature, but more evolved and luminous.