acrux constellation

acrux constellation插图

What type of star is Acrux?

Acrux is the most southern of the star s in the constellation. In addition to it being the brightest in the constellation, Acrux is also one of the brightest stars in the night sky, thirteenth brightest to be precise. Gacrux is a supergiant red star, in fact it is the nearest supergiant stars in the galaxy.

How many stars are in the Crux constellation?

Crux has one star with known planets and contains no Messier objects. The brightest star in the constellation is Acrux, Alpha Crucis, with an apparent magnitude of 0.77.

What is the origin of the constellation Acrux?

Unlike many star names, which are Arabic, Latin or Greek proper names, Acrux is simply a combination of “A” (for Alpha) and Crux as the name of the constellation. Not of classical derivation at all, it was a name coined by Elijah Hinsdale Burritt, a Connecticut farm boy turned celestial cartographer, circa 1835.

Where can Acrux be seen?

Acrux is the base of the constellation Crux, or the Southern Cross. It is best visible from Earth in areas that are farther south than 27 degrees N, such as Hawaii. Acrux’s location is:

What constellation is Acrux in?

Acrux, Alpha Crucis (α Cru), is a multiple star system located in the constellation Crux. It is the brightest of the stars that form the Southern Cross, one of the best known asterisms in the southern sky. Acrux lies at a distance of 320 light years from Earth. With a combined apparent magnitude of 0.76, it is the 12th brightest star in the sky. It shares the 12th place with Altair in the northern constellation Aquila. The two stars are usually only slightly brighter than the variable Aldebaran (Alpha Tauri), Antares (Alpha Scorpii) and Spica (Alpha Virginis), but are outshined by Achernar (Alpha Eridani), Betelgeuse (Alpha Orionis) and Hadar (Beta Centauri).

Why is Alpha Crucis D called Alpha Crucis D?

One of them has been designated Alpha Crucis D (or P) because it is separated by only 2’’ from Acrux C. It is a 15th magnitude star, likely of the spectral type M0 V.

Why is the star of Acrux visible?

Acrux was visible to most northern observers in ancient times. Due to the Earth’s axial pre cession, it has since shifted below the horizon. In ancient Greece and Rome, the stars of Crux were visible and considered part of Centaurus constellation. Acrux marked the Centaur’s right hind foot. In old Indian astronomy, the star was called Tri-shanku.

What are the three components of the optical system?

These two components are designated Alpha 1 Crucis and Alpha 2 Crucis and commonly referred to as Acrux A and Acrux B. The third component, Acrux C, is also visible in small telescopes. It is more distant from the two brighter …

How long is Acrux C?

The two components have an orbital period of 1 to 5 hours and a dim visual companion about 2.1’’ away. The estimated age of Acrux C is about 12 million years. The properties of the star’s spectroscopic companion are unknown, but it is believed to be more massive than the Sun.

How far is Acrux from Earth?

Acrux lies at a distance of 320 light years from Earth. With a combined apparent magnitude of 0.76, it is the 12th brightest star in the sky. It shares the 12th place with Altair in the northern constellation Aquila.

Which star is southernmost?

Acrux is the southernmost first magnitude star. At a declination of -63° 05’ 56.7343’’, it lies more than 2 degrees more southerly than its brighter neighbour Alpha Centauri (–60° 50′ 02.3737’’). Acrux and Gacrux are among the 58 stars selected for navigation.

What constellation is the Centaur?

Bayer outlined the constellation Crux over the hind feet of the Centaur ( Centaurus ), these now are alpha Crux (α, Acrux ), beta (β, Mimosa ), gamma (γ, Gacrux ), and delta (δ, unnamed), — alpha (α, Acrux) at the foot of the Cross, gamma (γ, Gacrux ), at the top, with beta (β, Mimosa ), and delta (δ, unnamed), as the transverse

Why are there no ancient legends or mythology associated with the stars in Crux?

There are no ancient legends or mythology associated with these large stars in Crux because the Cross constellation was unknown to the classicists by its present title, its four chief stars being noted by Ptolemy in Egypt where it was visible as a part of the Centaur Centaurus, which now surrounds it on three sides.

Why are there no legends about the stars in Crux?

There are no ancient legends or mythology associated with these large stars in Crux because the Cross constellation was unknown to the classicists by its present title, its four chief stars being noted by Ptolemy in Egypt where it was visible as a part of the Centaur Centaurus, which now surrounds it on three sides.

What is the meaning of the word "crux"?

“Crux is said to give perseverance, but many burdens, trials and responsibilities, together with much suffering and many hardships. In connection with rulerships of countries it may be noted that Brazil was named the Land of the Holy Cross by the discoverer Cabral on May 1st 1500, and that the constellation Crux has been represented on the postage stamps of that country”. [ Robson, p.41.]

Who wrote the book Fixed Stars and Constellations in Astrology?

Fixed Stars and Constellations in Astrology, Vivian E. Robson, 1923].

What is the name of the constellation Acrux?

History and mythology of Acrux. Unlike many star names, which are Arabic, Latin or Greek proper names, Acrux is simply a combination of “A” (for Alpha) and Crux as the name of the constellation.

Where can I see the star Acrux?

The star Acrux is the 13th brightest star in all the sky. Because it’s located far to the south of the sky’s equator, this star can’t be seen from much of North America. You need to be south of central Florida or south Texas. Observers in Hawaii sometimes tell us they’ve seen it.

What is the name of the star at the bottom of the Southern Cross?

The star Acrux marks the bottom of the Southern Cross. Image via Alain r/ Wikimedia Commons. The star Acrux – aka Alpha Crucis – is the brightest star in the constellation of the Southern Cross. This constellation’s official name is Crux. The star Acrux is the 13th brightest star in all the sky. Because it’s located far to the south …

What is the brightest star in Cygnus?

Interestingly, however, the brightest star in Cygnus, Deneb, is virtually the same apparent magnitude as Mimosa, the 2nd-brightest star in Crux. Both are bright blue stars of magnitude 1.25, ranking as the 19th (Mimosa) and 20th (Deneb) brightest stars in the sky. Many point out that Crux, of which Acrux is the primary star, …

How far south is Acrux?

Image via Starfield Observatory. How to see Acrux. You need to be south of about 27 degrees N. latitude – that is, no more north than 27 degrees north of the equator – to see Acrux and the Southern Cross. The farther south the better.

Which star is brighter, Mimosa or Acrux?

Nearby Mimosa, or Beta Crucis, is fainter than Acrux with a magnitude of 1.25; Mimosa is the 19th brightest star in all the heavens. Two nearby and brighter stars, Alpha Centauri (the most nearby star, in fact, and a triple star system at that) and Beta Centauri (Hadar), are known as the Southern Pointers. A line drawn from Alpha …

Which star is closest to the horizon?

If you are in the Northern Hemisphere, facing south to see them, the star Acrux marks the bottom of the Southern Cross and is thus the star nearest the horizon. At a magnitude of 0.77, Acrux is the southernmost 1st-magnitude star, that is, the southernmost of the brightest stars in our sky. Nearby Mimosa, or Beta Crucis, is fainter than Acrux with a magnitude of 1.25; Mimosa is the 19th brightest star in all the heavens.

What is the smallest constellation in the world?

Crux is the smallest of the 88 constellations, occupying an area of only 68 square degrees. It is located in the third quadrant of the southern hemisphere (SQ3) and can be seen at latitudes between +20° and -90°. The neighboring constellations are Centaurus and Musca.

Where is the coalsack nebula?

The Coalsack Nebula is a famous dark nebula, easily seen as a large dark patch in the southern region of the Milky Way. It stretches across nearly seven by five degrees of the sky, crossing over into the neighbouring constellations, Centaurus and Musca. It is between 30 and 35 light years in radius.

How many days does Theta-2 Crucis orbit?

It has a visual magnitude of 4.30. Theta-2 Crucis is also a spectroscopic binary star, composed of a pair of stars that orbit each other with a period of 3.4280 days. The star system has a stellar classification of B2 IV. It is about 750 light years distant from the solar system and has an apparent magnitude of 4.72.

How are Alpha and Crucis separated?

The two are separated by four arc seconds. Both stars are very hot, almost class O, and their respective luminosities are 25,000 and 16,000 times that of the Sun. Alpha-1 Crucis is a spectroscopic double, with 14th and 10th magnitude components orbiting each other with a period of 76 days.

What is the meaning of the word "crux"?

Crux means “the cross” in Latin. Ancient Greeks considered Crux to be a part of the constellation Centaurus. Even though its stars were charted on most celestial globes, it was not until 1679 that it became a constellation in its own right. It was the French astronomer Augustin Royer who formally separated Crux from Centaurus. Some historians credit the Dutch astronomer Petrus Plancius for creating the constellation in 1613, as it was published by Jakob Bartsch in 1624.

What is the Southern Cross?

Crux, or the Southern Cross, is a prominent constellation in the southern sky. It is the smallest of all 88 constellations. In spite of its size, Crux is one of the best known constellations in the southern hemisphere. It is easily recognizable for the cross-shaped asterism, the Southern Cross, formed by its five brightest stars.

How many stars are in the constellation Crux?

Crux contains six named stars. The proper names of stars that have been officially approved by the International Astronomical Union (IAU) are Acrux, Gacrux, Ginan, Imai, Mimosa, and Tupã. Crux constellation map by IAU and Sky&Telescope magazine.

Why is Acrux so bright?

Acrux is one of the brightest stars in the sky, but its brightness gets a boost because it is actually a multiple-star system. Three stars make up the system, and astronomers debate whether or not a fourth star "belongs" to the trio.

How many stars are there in Alpha 1?

The main star, Alpha-1, is actually two stars — a spectroscopic binary, meaning that the two stars can only be resolved individually by looking at their orbital motions’ effects on the spectrum, according to astronomer Jim Kaler. The other star is Alpha-2.

Where is Crux in the constellation Octans?

Crux points almost due north-south. You follow the line south through Gamma Crucis and Acrux (Alpha Crucis) to arrive near the South Celestial Pole in the constellation Octans.

What would happen if two stars were so close to each other?

With two stars so close to each other in the system, interesting things could happen at the end of their lifespan. The masses of the twin Alpha-1 stars suggest they could go supernova, said Kaler.

Where is the Southern Cross visible?

The star system has been viewed for hundreds of years on Earth. About 2,000 years ago, the Southern Cross was visible from the latitude of Jerusalem (almost 32 degrees N). Some people say Acrux was the star of Bethlehem that led the Magi to the baby Jesus.

Where is the constellation Acrux?

Acrux is the base of the constellation Crux, or the Southern Cross. It is best visible from Earth in areas that are farther south than 27 degrees N , such as Hawaii. Acrux’s location is:

Is the B subgiant related to Alpha 1?

Astronomers have also noted a B-subgiant that is 90 arcseconds away from the triplet in Earth’s sky, but it likely is unrelated to Alpha-1 and Alpha-2, Darling said. Astronomer Jim Kaler disagrees: "It more or less shares Acrux’s motion through space, and appears as if it might be gravitationally bound to the inner trio," he wrote on his website.

Did you know?

In the year 400 AD, the constellation of Crux was invisible for most of Europe, and thus the Europeans did not rediscover Crux until the great naval expeditions of the late 15 th and early 16 th centuries.

What is the smallest constellation in the sky?

The constellation of Crux is the smallest out of all the 88 modern constellations, stretching for around 68 square degrees in the sky. The name, Crux, comes from Latin and it translates to “Cross” – since the constellation is dominated by a cross-shaped or kite-shaped-like asterism commonly known as the Southern Cross.

What is the name of the constellation that is centered on four stars in the southern sky?

July 14, 2020. Crux is a constellation centered on four stars in the southern sky, in a bright portion of the Milky Way. It is among the most easily distinguishable constellations since its asterism stars have an apparent magnitude brighter than +2.8.

What are the stars in the Southern Cross?

The five main stars of Crux that comprise the Southern Cross asterism are Acrux, Mimosa, Gacrux, Imai, and Ginan. The brightest star in the constellation of Crux is Acrux, which is a triple star system having a visual magnitude of 0.8.

How far away is Imai from the Sun?

Imai is located at around 345 light-years away from us. It is 10,000 times brighter than our Sun, having 890% of its mass, and 800% of its radius. Imai has an effective temperature of around 22,570 K. It is a candidate Beta Cephei variable, exhibiting subtle changes in brightness over 3.7 hours.

How far out is Crux in the sky?

Crux spreads out for around 68 square degrees in the sky. Crux is not visible north of “20 o in the northern hemisphere, and it is circumpolar south of 34 o S, this means that it never sets below the horizon. On the celestial sphere, Crux is exactly opposite the constellation Cassiopeia. Right Ascension: 12.6h.

How many stars are brighter than magnitude 6.5?

Within the borders of Crux, there are around 49 stars that are brighter or equal to apparent magnitude 6.5. Unusually, a total of 15 of the 23 brightest stars in Crux are spectrally blue-white B-type stars.

What is the closest star to the Sun in 2021?

July 12, 2021. Alpha Centauri is the nearest star system to the Sun, located at a distance of only 4.37 light years or 1.34 parsecs from Earth. It is the brightest star in Centaurus constellation and the third brightest star in sky.

How far is Alpha Centauri from the Sun?

Alpha Centauri is the nearest star system to the Sun, located at a distance of only 4.37 light years or 1.34 parsecs from Earth. It is the brightest star in Centaurus constellation and the third brightest star in sky.

What is the name of the dark nebula in the sky?

Coalsack Nebula. The Coalsack Nebula is one of the best known dark nebulae in the sky, along with the nearby Dark Doodad Nebula and the Horsehead Nebula. The Coalsack is located in the southern constellation Crux and overlaps into the neighbouring constellations Musca and Centaurus.

Where is the Jewel Box Cluster located?

The Jewel Box Cluster, also known as the Kappa Crucis Cluster, is an open star cluster located in the southern constellation Crux. The cluster has…. Read More ».

How far away is Gamma Crucis from Earth?

YouTube. Gamma Crucis (Gacrux) is a red giant that is approximately 88 light years distant from Earth. It is the third brightest star in the Crux constellation and the 26th brightest star in the sky. Located about 400 light years distant from Earth, this binary star is composed of a M4 red dwarf star and a A3 white dwarf star.

Which star was used to mark due south?

It is known that Amerigo Vespucci mapped the stars of Crux on his expedition to South America in 1501, and with good reason! Two of the stars of Crux (Alpha and Gamma, Acrux and Gacrux respectively) are commonly used to mark due south.

How many stars are in the Kappa Crucis Cluster?

the “Jewel Box” or “Herschel’s Jewel Box”), an open star cluster that is located approximately 6,440 light years from Earth. It contains roughly 100 stars and is one of the youngest clusters ever discovered (only 14 million years old).

What is the meaning of the Crux constellation?

Name and Meaning: For the people of the Southern Hemisphere, the Crux constellation has a great deal of cultural significance. The Incas knew the constellation as Chakana (Quechua for “the stair”), and a stone image of the stars was found in Machu Picchu, Peru. To the Maori, the constellation was known as Te Punga, or “the anchor”, …

What constellation is Tammy Plotner?

Welcome to another edition of Constellation Friday! Today, in honor of the late and great Tammy Plotner, we take a look at the “Southern Cross” – the Crux constellation. Enjoy!

How many constellations are there in the southern hemisphere?

Today, it has gone on to become one of the 88 modern constellations currently recognized by the International Astronomical Union (IAU).

What is the significance of the Southern Cross?

Because of this significance, the Southern Cross is represented on the flags of Australia, Papua New Guinea, New Zealand Brazil, and Brazil.

What is the name of the constellation that means the Southern Cross?

Crux is the 88th largest in terms of size in the night sky. The constellation name means The Southern Cross . It was not one of the original constellations that had been devised by Ptolemy, instead it was created by Johann Bayer years later. There are 4 stars that make up the main constellation.

Which constellation is closest to the Northern Hemisphere?

There is no specific northern hemisphere equivalent although the constellation Cygnus comes close due to its near cross shape. The constellation is surrounded on three sides by the more famous Centaurus constellation which contains the closest stars to us, Rigil Kentaurus and Proxima Centauri.

How many degrees does Crux take up?

The sky is not divided up equally between the constellations. Crux takes up 68.447 sq. degrees of the night sky which equates to 0.17% of the night sky.

Why can’t you go to one location and arrive at the constellation?

You can’t just go to one location and arrive at the constellation because the constellation is made up of stars at different locations and different distances. The nearest main star in the constellation is at a distance of 88.56 light years and the furthest main star is a distance of 345.15 light years.

What is the furthest star in the constellation?

The furthest star that is located in the constellation is HIP 58278 and it is 108721.1 light years away from the Sun. The furthest figure is derived from either the 1997 or 2007 Hipparcos star catalogue parallax figure and it has been known to produce distances that are wrong.

Why is Ursa Minor used in nagivation?

In the northern hemisphere, Ursa Minor is the navigation constellation because it contains Polaris, the Pole Star.

What is the equator of the zodiac?

The Celestial Equator is the projection of the terrestrial equator into space. The Ecliptic is the path that the Earth takes round the Sun. The Earth is titled at 23.44° which is why the two differ. The Zodiac constellations are based on the Ecliptic.

How to find the south celestial pole?

The star’s faintness makes it less useful than its northern counterpart Polaris, Alpha Ursae Minoris, for locating true south. The bright stars of Centaurus and Crux are used instead. The southern celestial pole can be found by extending an imaginary line from Gacrux through Acrux and drawing another line at a right angle to the imaginary line connecting the Southern Pointers. The point where the two lines intersect is close to the pole.

What constellation is Gacrux in?

Gacrux, Gamma Crucis (γ Cru), is a red giant star located in the southern constellation Crux. With an apparent magnitude of 1.63, it is the third brightest star in Crux and the 25th brightest star in the sky. It is only slightly fainter than Shaula in Scorpius and Castor in Gemini, and it just outshines Bellatrix in Orion, Elnath in Taurus and Miaplacidus in Carina constellation. At an approximate distance of 88.6 light years from Earth, Gacrux is the nearest red giant to the solar system and the brightest star of its class in the sky.

How far is Gacrux from Earth?

At an approximate distance of 88.6 light years from Earth, Gacrux is the nearest red giant to the solar system and the brightest star of its class in the sky. Gacrux is one of the four stars that form the Southern Cross, one of the most prominent asterisms in the southern celestial hemisphere. It is the northernmost (top) star …

What does the star on the Brazilian flag mean?

On the flag of Brazil, each star represents a Brazilian Federative Unit and Gacrux symbolizes the state of Bahia. In the culture of the Aranda and Luritja people of the Northern Territory in Australia, Gacrux is part of an asterism known as Iritjinga, meaning “the eagle-hawk.”.

What type of star is Gacrux?

Star type. Gacrux is a red giant of the spectral type M3.5 III. It has a mass about 1.5 times that of the Sun and has expanded to a size of 84 solar radii. With a temperature of 3,626 K, it shines with about 820 solar luminosities and appears distinctly reddish.

Where is Gacrux located?

Gacrux lies in the far southern sky and is invisible from most locations in the northern hemisphere. For southern observers, Gacrux is very easy to find because it is bright, part of the Southern Cross, and it has a pair of exceptionally bright stars, Alpha and Beta Centauri (the Southern Pointers) pointing at it.

Which star is the brightest in the sky?

Gacrux and Acrux are among the 58 stars selected for celestial navigation. Navigational stars are some of the brightest stars in the sky, selected because they are bright and can be easily identified. They stretch across 38 constellations, covering the area from the declination +89° to -70° of the celestial sphere.