What is Regulus, and where is it located in the night sky?

Regulus is the brightest object in the constellation Leo and is recognized as one of the brightest stars visible in the night sky. A constellation is a group of stars that form a recognizable pattern or outline in the night sky, typically representing an animal, mythological person or creature, or an inanimate object.

What is the Bayer designation for Regulus?

Regulus carries the Bayer designation of Alpha Leonis, which is often abbreviated as Alpha Leo or α Leo. The Bayer designation is a system of stellar nomenclature in which a specific star is identified by a Greek letter followed by the genitive form of its parent constellation's Latin name.

How far is the Regulus star system from the Solar System?

The Regulus system is located approximately 79 light-years from our Solar System. A light-year is a unit of distance in astronomy, representing the distance light travels in one Earth year, which is about 9.46 trillion kilometers or 5.88 trillion miles.

What kind of star system is Regulus, despite appearing as a single star?

Regulus appears as a single star to the unaided eye, but it is actually a quadruple star system, meaning it is composed of four stars organized into two distinct pairs. A star system is a small number of stars that orbit each other, bound by gravitational attraction.

What are the primary components of the Regulus A spectroscopic binary?

The spectroscopic binary Regulus A consists of a blue-white main-sequence star and its companion, which is a pre-white dwarf. A main-sequence star is a star that is fusing hydrogen into helium in its core, like our Sun, while a white dwarf is the dense, compact remnant of a low-to-medium-mass star that has exhausted most of its nuclear fuel.

What is the traditional name 'Regulus' derived from, and what does it mean?

The traditional name Regulus is derived from Latin, meaning 'prince' or 'little king'. This name reflects its prominence and brightness in the night sky.

Which organization standardized the proper name 'Regulus' for this star?

In 2016, the International Astronomical Union (IAU) organized a Working Group on Star Names (WGSN) to catalog and standardize proper names for stars, and 'Regulus' was among the first names approved and entered into the IAU Catalog of Star Names.

What are some other historical and cultural names for Regulus?

Regulus has several historical and cultural names, including Qalb al-Asad from Arabic, meaning 'the heart of the lion,' and its Greek equivalent, Kardia Leontos. In Chinese astronomy, it is known as the Fourteenth Star of Xuanyuan, the Yellow Emperor, and in Indian astronomy, it corresponds to the Nakshatra Magha, meaning 'the bountiful' or 'the Mighty'.

What was Regulus called by the Babylonians and Persians?

The Babylonians referred to Regulus as Sharru, meaning 'the King,' and it marked the 15th ecliptic constellation. In Persia, it was known as Miyan, meaning 'the Centre,' and was also considered one of the four 'royal stars' of the Persian monarchy.

What is the overall apparent magnitude of the Regulus system, and which component contributes most to its brightness?

The Regulus system as a whole has an apparent magnitude of +1.35, making it the twenty-first brightest star in the night sky. The light output of the system is predominantly from Regulus A.

What are the individual apparent magnitudes of Regulus B and Regulus C?

If observed in isolation, Regulus B would have an apparent magnitude of +8.1, making it visible with binoculars, while Regulus C, the faintest of the directly observed stars, has an apparent magnitude of +13.5 and would require a substantial telescope to be seen. Apparent magnitude is a measure of how bright a star appears from Earth.

What is the angular distance between Regulus A and the Regulus BC pair, and can they be observed by amateur astronomers?

The Regulus BC pair is separated from Regulus A by an angular distance of 177 arc-seconds, which makes them visible in amateur telescopes. An arc-second is a unit of angular measurement, equal to 1/3600 of a degree.

How close is Regulus to the ecliptic, and what astronomical events does this proximity cause?

Regulus is located 0.465 degrees from the ecliptic, which is the closest of the bright stars to this plane. This proximity means it is frequently occulted by the Moon, and occasionally by planets and asteroids. The ecliptic is the apparent path of the Sun across the celestial sphere over the course of a year.

How often do lunar occultations of Regulus occur?

Lunar occultations of Regulus occur in spates approximately every 9.3 years, a cycle influenced by lunar precession. Lunar precession refers to the slow, gradual change in the orientation of the Moon's orbit over time.

When was the last planetary occultation of Regulus, and when is the next one predicted?

The last occultation of Regulus by a planet occurred on July 7, 1959, by Venus. The next predicted planetary occultation will also be by Venus, on October 1, 2044.

What significant observation was made during the occultation of Regulus by asteroid 166 Rhodope in 2005?

During the occultation of Regulus by the asteroid 166 Rhodope on October 19, 2005, differential bending of light was measured, and these measurements were found to be consistent with the predictions of general relativity. General relativity is Albert Einstein's theory of gravity, which describes gravity not as a force, but as a curvature of spacetime caused by mass and energy.

When is Regulus best observed in the northern hemisphere, and when is it obscured by the Sun?

Regulus is best seen in the evening during the northern hemisphere's late winter and spring. It is obscured by the Sun's glare for about a month on either side of August 22–24, making it difficult to observe during that period.

What is the heliacal rising of Regulus, and when does it typically occur?

The heliacal rising of Regulus, which is its first pre-sunrise appearance after a period of invisibility due to the Sun's glare, typically occurs late in the first week of September or in the second week. This event was historically significant for ancient civilizations in marking seasons or agricultural cycles.

What is the evolutionary stage of Regulus A?

Regulus A is classified as a blue straggler, which is a star that appears to be hotter and bluer than other stars in its cluster that formed at the same time, suggesting it has either gained mass or merged with another star.

What is the spectral type of Regulus A?

The spectral type of Regulus A is B8 IVn. Spectral type is a classification system for stars based on their spectral characteristics, which are indicative of their surface temperature and other properties.

What are the U-B and B-V color indices for Regulus A?

Regulus A has a U-B color index of -0.36 and a B-V color index of -0.11. Color indices are differences in the magnitudes of a star measured at different wavelengths, used by astronomers to determine a star's temperature and spectral type.

Is Regulus A considered a variable star?

Regulus A is suspected to be a variable star, meaning its brightness as seen from Earth may fluctuate over time. Variable stars can change in luminosity due to intrinsic physical processes or external factors like eclipses.

What is the evolutionary stage of the Regulus BC pair?

The Regulus BC pair is in the main sequence evolutionary stage. Main sequence stars are those that are actively fusing hydrogen into helium in their cores, representing the longest and most stable phase of a star's life.

What are the spectral types of Regulus B and Regulus C?

Regulus B has a spectral type of K2 V, and Regulus C has a spectral type of M4 V. These classifications indicate that both are main-sequence stars, with K2 V being an orange dwarf and M4 V being a red dwarf, both cooler and less massive than the Sun.

What are the U-B and B-V color indices for Regulus BC?

Regulus BC has a U-B color index of +0.51 and a B-V color index of +0.86. These positive values indicate cooler temperatures compared to Regulus A.

What is the radial velocity of Regulus A?

The radial velocity of Regulus A is 4.39 ± 0.09 kilometers per second. Radial velocity measures the speed at which a star is moving towards or away from an observer, determined by shifts in its spectral lines.

What is the proper motion of Regulus A?

Regulus A exhibits a proper motion of -248.73 ± 0.35 milliarcseconds per year in Right Ascension and 5.59 ± 0.21 milliarcseconds per year in Declination. Proper motion is the apparent angular motion of a star across the celestial sphere as seen from Earth, independent of its radial velocity.

What is the parallax of Regulus A, and what does it indicate about its distance?

The parallax of Regulus A is 41.13 ± 0.35 milliarcseconds. Parallax is the apparent displacement of an object due to a change in the observer's point of view, and in astronomy, it is used to calculate the distance to stars; a larger parallax indicates a closer star.

What is the absolute magnitude of Regulus A?

Regulus A has an absolute magnitude of -0.57. Absolute magnitude is a measure of a star's intrinsic brightness, defined as the apparent magnitude it would have if it were located at a standard distance of 10 parsecs from Earth.

What is the radial velocity of Regulus B?

Regulus B has a radial velocity of +6.72 kilometers per second. A positive radial velocity indicates that the star is moving away from the observer.

What is the proper motion of Regulus B?

Regulus B has a proper motion of -254.399 milliarcseconds per year in Right Ascension and 8.127 milliarcseconds per year in Declination.

What is the parallax of Regulus B?

The parallax of Regulus B is 41.2745 ± 0.0270 milliarcseconds.

What is the absolute magnitude of Regulus B?

Regulus B has an absolute magnitude of 6.20.

What is the proper motion of Regulus C?

Regulus C has a proper motion of -224.824 milliarcseconds per year in Right Ascension and +9.091 milliarcseconds per year in Declination.

What is the parallax of Regulus C?

The parallax of Regulus C is 41.2424 ± 0.0589 milliarcseconds.

What is the absolute magnitude of Regulus C?

Regulus C has an absolute magnitude of 11.56.

What are the primary and companion stars in the inner orbit of Regulus A?

The primary star in the inner orbit of Regulus A is designated α Leo Aa (HD 87901 A), and its companion is α Leo Ab (HD 87901 B). These designations help astronomers distinguish between components in multiple star systems.

What is the orbital period of Regulus Aa and Ab?

Regulus Aa and Ab complete an orbit around their common center of mass in approximately 40.102 ± 0.002 days. This relatively short period indicates a close binary system.

What is the semi-major axis of the orbit for Regulus Aa and Ab?

The semi-major axis of the orbit for Regulus Aa and Ab is 74 solar radii. The semi-major axis is half of the longest diameter of an elliptical orbit, representing the average distance between the orbiting bodies.

What is the eccentricity of the orbit for Regulus Aa and Ab?

The eccentricity of the orbit for Regulus Aa and Ab is assumed to be 0, indicating a perfectly circular orbit. Eccentricity is a measure of how much an orbit deviates from a perfect circle, with 0 being a circle and values closer to 1 being more elongated.

What is the semi-amplitude (K1) of Regulus Aa?

The semi-amplitude (K1) of Regulus Aa is 7.58 ± 0.12 kilometers per second. In spectroscopy, K1 refers to the semi-amplitude of the radial velocity curve for the primary star in a binary system, which helps determine orbital parameters.

What is the mass of Regulus A's primary star?

The primary star of Regulus A has a mass of approximately 4.15 ± 0.06 solar masses. A solar mass is a standard unit of mass in astronomy, roughly equal to the mass of the Sun.

What are the equatorial and polar radii of Regulus A?

Regulus A has an equatorial radius of 4.21 solar radii (with a margin of +0.07/-0.06) and a polar radius of 3.22 solar radii (with a margin of +0.05/-0.06). This difference highlights its oblate shape due to rapid rotation.

What is the luminosity of Regulus A?

Regulus A has a luminosity of 341 solar luminosities (with a margin of +27/-28). Luminosity is the total amount of energy emitted by a star per unit time, often expressed in terms of the Sun's luminosity.

What is the surface gravity (log g) of Regulus A?

The surface gravity (log g) of Regulus A is 3.54 ± 0.09 cgs. Surface gravity is the gravitational acceleration experienced at the surface of a celestial body, and log g is its logarithm, commonly used in stellar astrophysics.

What are the equatorial and polar temperatures of Regulus A?

Regulus A has an equatorial temperature of 11,010 Kelvin and a polar temperature of 14,520 Kelvin. This temperature difference is a result of gravity darkening caused by its rapid rotation.

What is the metallicity [Fe/H] of Regulus A?

The metallicity [Fe/H] of Regulus A is +0.21 dex. Metallicity in astronomy refers to the abundance of elements heavier than hydrogen and helium in a star, often expressed as a logarithmic ratio relative to the Sun.

What is the rotation period of Regulus A's primary star, and how does it compare to the Sun's rotation?

The primary star of Regulus A spins extremely rapidly, with a rotation period of only 15.9 hours, which is significantly faster than the Sun's rotation period of 25 days. This rapid rotation causes its highly oblate shape.

What is 'gravity darkening' in the context of Regulus A?

Gravity darkening is a phenomenon where the photosphere (the visible surface) at Regulus A's poles is considerably hotter and five times brighter per unit surface area than its equatorial region. This occurs because the rapid rotation causes the equator to bulge and be further from the star's center, resulting in lower surface gravity and thus lower temperature and brightness.

Why does Regulus A emit polarized light?

Regulus A emits polarized light due to its extremely rapid rotation, which causes it to have a highly oblate shape. Polarization refers to the orientation of light waves, and in this case, it's influenced by the star's distorted shape and gravity darkening.

What is the mass of Regulus Ab?

Regulus Ab has a mass of 0.31 ± 0.10 solar masses. This mass is consistent with its classification as a pre-white dwarf.

Regulus Wiki: Regulus: Unveiling the Celestial Monarch of Leo

Dive in with Flashcard Learning!

When you are ready...
🎮 Play the Wiki2Web Clarity Challenge Game🎮

Overview

The Brightest in Leo

Regulus, formally designated Alpha Leonis (α Leonis), stands as the preeminent luminary within the constellation Leo, and is recognized as one of the brightest stars observable in the nocturnal sky. This seemingly singular point of light is, in fact, an intricate quadruple star system, comprising four distinct stellar bodies organized into two gravitationally bound pairs. Positioned approximately 79 light-years from our Solar System, Regulus offers a fascinating case study in stellar multiplicity and evolution.

The Lion's Head Asterism

Regulus is not merely a solitary star but a pivotal component of a prominent asterism known as 'the Sickle'. This distinctive pattern, which delineates the head of the constellation Leo, includes Regulus alongside five slightly fainter stellar counterparts: Zeta Leonis, Mu Leonis, Gamma Leonis, Epsilon Leonis, and Eta Leonis. The collective brilliance and arrangement of these stars have long captivated observers and served as a celestial marker.

Nomenclature

Etymological Roots

The traditional name "Rēgulus" originates from Latin, signifying 'prince' or 'little king', a fitting appellation for the dominant star in the celestial lion. Its Greek equivalent, "Basiliskos," also carries the connotation of royalty or a diminutive sovereign. This regal association underscores its historical importance and prominent position in the night sky.

Cross-Cultural Designations

Regulus has been known by various names across diverse ancient cultures, each reflecting its perceived significance:

Arabic: "Qalb al-Asad," translating to 'the heart of the lion,' a name that echoes the Greek "Kardia Leontos" and its Latin counterpart "Cor Leōnis."
Babylonian: Referred to as "Sharru," meaning 'the King,' and was instrumental in marking the 15th ecliptic constellation.
Indian: Known as "Maghā," or 'the Mighty,' within Indian astronomy, corresponding to a specific Nakshatra.
Persian: Designated "Miyan," meaning 'the Centre,' and was revered as one of the four 'royal stars' of the Persian monarchy.

Furthermore, Regulus was recognized as one of the fifteen Behenian fixed stars by medieval astrologers, associated with specific terrestrial elements like granite and mugwort, and a unique Kabbalistic symbol.

Observation

Apparent Brightness

The Regulus system collectively ranks as the twenty-first brightest star in the night sky, boasting an apparent magnitude of +1.35. The majority of this luminosity emanates from Regulus A. Its companions, Regulus B and C, are considerably fainter; Regulus B presents as a magnitude +8.1 object, discernible with binoculars, while Regulus C, at magnitude +13.5, necessitates a substantial telescope for direct observation. The Regulus BC pair, however, is separated from Regulus A by an angular distance of 177 arc-seconds, making them resolvable with amateur astronomical equipment.

Celestial Alignments & Occultations

Regulus holds a unique position, being merely 0.465 degrees from the ecliptic, making it the closest bright star to this celestial path. Consequently, it is frequently occulted by the Moon, an event that occurs in recurring cycles approximately every 9.3 years due to lunar precession. The most recent series of lunar occultations spanned from December 2016 to July 2017, with each event visible from specific regions on Earth.

Occultations by planets such as Mercury and Venus are considerably rarer. The last recorded planetary occultation of Regulus occurred on July 7, 1959, by Venus, with the next predicted for October 1, 2044, also involving Venus. Other planets are not expected to occult Regulus for several millennia due to their orbital node positions.

Asteroid occultations, while less common, have also been observed. On October 19, 2005, the asteroid 166 Rhodope occulted Regulus, an event filmed in Italy where differential light bending consistent with general relativity was measured. Another occultation by the asteroid 163 Erigone was predicted for March 20, 2014, with its shadow path crossing New York and eastern Ontario; however, due to extensive cloud cover, no observations were successfully recorded.

Annual Visibility

While Regulus is best observed in the evening skies during the late winter and spring in the Northern Hemisphere, it remains visible at some point during the night throughout most of the year. There is a brief period, approximately a month on either side of August 22–24, when the Sun's proximity makes observation challenging due to glare. In late February, Regulus can be seen traversing the entire night sky. Its heliacal rising, the first pre-sunrise appearance, typically occurs in the late first or early second week of September. Notably, Venus passes very near Regulus around or just before its heliacal rising every 8 years, as observed on September 5, 2022.

Stellar System

Regulus A: The Rapid Rotator

Regulus A is the dominant component of the system, a blue-white subgiant star of spectral type B8 IVn. It is a spectroscopic binary, orbited by a companion star of at least 0.3 solar masses, which is believed to be a pre-white dwarf. These two stars complete an orbit around their common center of mass in approximately 40 days. The primary star, Regulus A, possesses about 4.15 times the mass of our Sun and exhibits an extraordinarily rapid rotation, completing a full rotation in just 15.9 hours (compared to the Sun's 25 days). This extreme rotational velocity causes Regulus A to adopt a highly oblate, or flattened, spheroid shape.

The rapid rotation leads to a phenomenon known as "gravity darkening," where the star's poles are considerably hotter and five times brighter per unit surface area than its equatorial region. The surface at the equator rotates at approximately 320 kilometers per second, which is 96.5% of the critical angular velocity at which the star would begin to break apart. This extreme distortion also causes Regulus A to emit polarized light. Initially, Regulus A was estimated to be a relatively young star, between 50 and 100 million years old. However, the presence of a white dwarf companion implies a system age of at least 1 billion years to account for the white dwarf's formation. This age discrepancy is resolved by a history of mass transfer from the companion onto a once-smaller Regulus A.

Regulus BC: The Distant Pair

Located approximately 5,000 Astronomical Units (AU) from Regulus A, the Regulus BC pair (also known as HD 87884) shares a common proper motion with Regulus A, suggesting a gravitational bond and a mutual orbital period spanning several million years. This pair itself is a close binary system, consisting of Regulus B, a K2V star, and Regulus C, an M4V star. Their orbital period around each other is estimated to be around 600 years, with a separation of 2.5 arcseconds recorded in 1942.

Candidate Brown Dwarf Companion

A more widely separated brown dwarf, SDSS J1007+1930, located 7.55 degrees from Regulus, is a candidate for being gravitationally bound to the Regulus system. This object exhibits a proper motion and radial velocity similar to Regulus B, along with a comparable metal abundance, hinting at a physical connection. Its estimated distance from Regulus is approximately 3.9 parsecs (about 12.6 light-years). If it were in a circular orbit, its orbital period would be around 200 million years, a duration comparable to the Sun's galactic year.

SDSS J1007+1930 is estimated to have a mass of roughly 60 Jupiter masses (0.06 solar masses), placing it below the hydrogen burning limit, thus classifying it as a substellar object incapable of sustained hydrogen fusion. Its effective temperature is approximately 1,600 Kelvin, with a spectral type of L9 or T0, categorizing it as an L dwarf or T dwarf. The extreme distance between this candidate and the main Regulus system makes its gravitational binding uncertain, and it may be susceptible to being stripped away by future stellar encounters due to its weak gravitational connection.

Regulus System Components Summary

The following table provides a concise summary of the key characteristics for the primary components of the Regulus stellar system:

Component	Separation (arcsec)	Projected Separation (AU)	Orbital Period	Spectral Type	Mass (M_☉)	App. Mag. (V)
Regulus A	0.015	0.356	40.1 days	B8 IVn	4.15	1.4 (combined)
Regulus A	0.015	0.356	40.1 days	pre-WD	0.31	1.4 (combined)
Regulus BC	2.1	60	600 years	K2V	0.78	8.1
Regulus BC	2.1	60	600 years	M4V	0.32	13.5
SDSS J1007+1930	27,200	800,000	200 million years (candidate)	L9	0.06	26

Orbital Dynamics

Regulus A's Inner Dance

The primary component, Regulus A, is a spectroscopic binary where the visible blue-white subgiant (Regulus Aa) is accompanied by a pre-white dwarf (Regulus Ab). These two stars are locked in a relatively tight orbit, completing a revolution around their common barycenter in approximately 40.102 days. The semi-major axis of this inner binary is estimated to be around 74 solar radii. Due to the highly distorted, oblate shape of Regulus Aa, the orbital motion of this pair may experience notable long-term perturbations, deviating from a purely Keplerian scenario, which typically assumes point-like masses.

The BC Pair's Mutual Orbit

Regulus B and Regulus C form a distinct binary system, orbiting each other with a period of approximately 600 years. Observations from 1942 indicated a separation of 2.5 arcseconds between these two stars. This pair, in turn, orbits the more massive Regulus A at a much greater distance. The combined Regulus A and Regulus BC system is thought to have an approximate orbital period of 130,000 years, with a projected separation of about 4400 AU (or 0.07 light-years).

Distant Companion's Trajectory

The candidate brown dwarf, SDSS J1007+1930, if indeed gravitationally bound to the Regulus system, would possess an extraordinarily wide orbit. Its estimated orbital period, assuming a circular path, would be around 200 million years. This immense distance and prolonged orbital period highlight the weak gravitational coupling, making its long-term association with Regulus subject to further verification and potentially vulnerable to disruption by other stellar encounters over cosmic timescales.

Cultural Associations

Ancient Royal Star

Regulus has held significant cultural and astrological importance across various civilizations. In ancient Persia, it was revered as one of the four 'royal stars,' celestial markers believed to govern the heavens and influence earthly affairs. This designation underscores its perceived power and prominence in the night sky, aligning with its Latin name meaning 'little king'.

Astrological Significance

Medieval astrologers recognized Regulus as one of the fifteen Behenian fixed stars, a group of stars believed to possess particular magical properties and influences. These stars were associated with specific gemstones, herbs, and Kabbalistic symbols, with Regulus linked to granite, mugwort, and a distinct Kabbalistic emblem. Such associations reflect a deep historical belief in the star's mystical and symbolic power.

Babylonian Astronomy

In the ancient Babylonian MUL.APIN, a comprehensive compendium of astronomical observations and celestial lore, Regulus was explicitly listed as "Lugal," meaning 'king.' It was further described as the "star of the Lion's breast," indicating its central and vital position within the constellation Leo. This early astronomical record highlights the enduring recognition of Regulus as a celestial monarch across millennia.

Teacher's Corner

Edit and Print this course in the Wiki2Web Teacher Studio

Edit and Print Materials from this study in the wiki2web studio

Click here to open the "Regulus" Wiki2Web Studio curriculum kit

Use the free Wiki2web Studio to generate printable flashcards, worksheets, exams, and export your materials as a web page or an interactive game.

True or False?

Test Your Knowledge!

Gamer's Corner

Are you ready for the Wiki2Web Clarity Challenge?

Learn about regulus while playing the wiki2web Clarity Challenge game.

Unlock the mystery image and prove your knowledge by earning trophies. This simple game is addictively fun and is a great way to learn!

Play now

Explore More Topics

Discover other topics to study!

heaven in christianity

interstate 69 in texas

opportunity zone

national wildlife area

list of wrestling observer newsletter awards

university of washington

manius aquillius consul 101 bc

rosslyn south africa

edmunds company

takedda

References

Regulus A and B are separated by 180 arcseconds, resulting in a projected separation of 4400 AU/0.07 light years. The combined binary system may have an approximate orbital period of 130,000 years.

A full list of references for this article are available at the Regulus Wikipedia page

Feedback & Support

To report an issue with this page, or to find out ways to support the mission, please click here.

Disclaimer

Important Notice

This page was generated by an Artificial Intelligence and is intended for informational and educational purposes only. The content is based on a snapshot of publicly available data from Wikipedia and may not be entirely accurate, complete, or up-to-date.

This is not professional astronomical or scientific advice. The information provided on this website is not a substitute for consulting peer-reviewed scientific literature, official astronomical databases, or seeking advice from qualified astrophysicists or astronomers for specific research or observational needs. Always refer to authoritative scientific sources and consult with experts for precise data and interpretations. Never disregard professional scientific advice because of something you have read on this website.

The creators of this page are not responsible for any errors or omissions, or for any actions taken based on the information provided herein.

Regulus: Unveiling the Celestial Monarch of Leo

💡 Dive in with Flashcard Learning! 💡

Overview 🌌

👑 The Brightest in Leo

🦁 The Lion's Head Asterism

Nomenclature 📜

👑 Etymological Roots

🌍 Cross-Cultural Designations

Observation 🔭

✨ Apparent Brightness

🌙 Celestial Alignments & Occultations

🗓️ Annual Visibility

Stellar System ✨

🌀 Regulus A: The Rapid Rotator

👯 Regulus BC: The Distant Pair

🔭 Candidate Brown Dwarf Companion

📊 Regulus System Components Summary

Orbital Dynamics 🛰️

🔄 Regulus A's Inner Dance

🤝 The BC Pair's Mutual Orbit

❓ Distant Companion's Trajectory

Cultural Associations 🏛️

👑 Ancient Royal Star

✨ Astrological Significance

📜 Babylonian Astronomy

Teacher's Corner 🧑‍🏫

Edit and Print this course in the Wiki2Web Teacher Studio

True or False? 🤔

❓ Test Your Knowledge! ❓

Gamer's Corner 🎮

Are you ready for the Wiki2Web Clarity Challenge?

Explore More Topics

📜 Discover other topics to study!

References

📜 References

Feedback & Support 👍

To report an issue with this page, or to find out ways to support the mission, please click here.

Disclaimer ⚠️

📜 Important Notice

Dive in with Flashcard Learning!

Overview

The Brightest in Leo

The Lion's Head Asterism

Nomenclature

Etymological Roots

Cross-Cultural Designations

Observation

Apparent Brightness

Celestial Alignments & Occultations

Annual Visibility

Stellar System

Regulus A: The Rapid Rotator

Regulus BC: The Distant Pair

Candidate Brown Dwarf Companion

Regulus System Components Summary

Orbital Dynamics

Regulus A's Inner Dance

The BC Pair's Mutual Orbit

Distant Companion's Trajectory

Cultural Associations

Ancient Royal Star

Astrological Significance

Babylonian Astronomy

Teacher's Corner

True or False?

Test Your Knowledge!

Gamer's Corner

Discover other topics to study!

References

Feedback & Support

Disclaimer

Important Notice