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Quickie Questions - Astronomy Anomalies - Stars - Windows to the Universe

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Quickie Questions - Astronomy Anomalies - Stars

Date Answered Questioner (age, location) Question Answer

February 9, 2010jheszabel (age 17, philippines) why is the presence of large amount of helium in the spectrum of a star generally considered to be a sign of age ? Because helium is a product of the thermonuclear fusion inside a star. Thus, an old star has lost most or all of its hydrogen, leaving just a core of helium.
February 9, 2010jheszabel dela cruz (age 17, philippines) why is the presence of large amount of helium in the spectrum of a star generally considered to be a sign of age ? Because helium is a product of the thermonuclear fusion inside a star. Thus, an old star has lost most or all of its hydrogen, leaving just a core of helium.
February 5, 2010Erica (age 20, Michigan) If the stars appear to move clockwise and counterclockwise at the Poles, how do they appear to move at the equator? Stars move couterclockwise, rising from the east and setting in the west, following a kind of rotational path around an apparent "pole" formed by the North Star.
February 4, 2010Allie (age 16, Illinois) Who and when was the virgo constellation found? The Virgo Constellation has been known for a very long time. One of the earlier mentions was by Babylonian Mul.Apin (between 686 BC and 1000 BC), who mentioned that this constellation was known as "The Furrow" , representing the goddess Shala's ear of grain or corn. More information here.
February 3, 2010lyric (age 19, illinois) who discovered the constellation ursa minor Callimachus (D.L. I.22) reported that Thales 'discovered' Ursa Minor. This means only that he recognized the advantages of navigating by Ursa Minor, rather than by Ursa Major, as was the preferred method of the Greeks. Ursa Minor, a constellation of six stars, has a smaller orbit than does the Great Bear, which means that, as it circles the North Pole, Ursa Minor changes its position in the sky to a lesser degree than does the Great Bear. Thales offered this sage advice to the mariners of Miletus, to whom it should have been of special value because Miletus had developed a maritime trade of economic importance. (Extracted from http://www.utm.edu/research/iep/t/thales.htm#SH8e)
February 1, 2010sara (age 13, Georgia) Explain what effects the fusion of hydrogen brings about in a developing star. The Sun, like most stars, generates its energy by nuclear fusion of hydrogen nuclei into helium. Nuclear fusion is an atomic reaction in which many nuclei (the centers of atoms) combine together to make a larger one (a different element). The result of this process is the release of a lot of energy.
January 27, 2010stefano (age 56, ITALIA) .I see that there is a relation between the activity cycle and the rotation speed of a star.
Couldn't be that there is a relation between the activity cycle and the mass of a star too?Thank you very much.Regards.Stefano
Although the total mass of a star is the principal determinant in its evolution, I don't believe there are significant mass changes during a star's activity cycle.
January 27, 2010Nancy (age 13, tooele) Why do our constellations have myths anyway? What good will that do? Since long ago, people around the world have associated the heavens, the stars, and the patterns they make in the sky with their gods and goddesses. Links from this page will take you to descriptions of the role of selected stars, star patterns, and related gods and goddesses in various cultures
January 15, 2010miya (age 11, Michigan) what r 2 constellations scientific name and nikname that i could c n Michigan? There are many, for example, the constellations that form the Northern Circumpolar Sky are Cassiopeia, Cepheus, Draco, Ursa Major, and Ursa Minor.
January 12, 2010Gabbi (age 10, Colorado) what is special about constellations Constellations are formed of bright stars which appear close to each other on the sky, but are really far apart in space. The shapes you see all depend on your point of view. Many societies saw patterns among the stars with gods and goddesses or stories from their culture. More information can be found in our web page Constellations.
January 11, 2010Paige (age 17, Colorado Springs/Colorado) What are some latin sources for the Roman myth of Sagittarius, and were can I find them? Some information can be found in our web page Sagittarius and in Sagittarius in Myth.
January 11, 2010Corey (age 16, Pennsylvania) What is the Spectral Class of the three Brightest stars in the andromeda constellation The three brightest stars in the Andromeda Constellation are Alpha (Alpheratz, Spectral type B8IVpMnHg), Beta (Mirach, M0IIa), and Gamma (Almaak, K3IIb+A0V).
January 4, 2010Brenda (age 50, Georgia) Can the southern cross be seen from Jamaica/ Cayman Islands or while you are in the ocean south of Cuba? Yes!, if you live in the Northern Hemisphere, you must be south of latitude 30 degrees to begin observing Crux, one of the smallest, but most easily recognized constellations in the sky. Crux lies along the Milky Way and is surrounded by Centaurus, the Centaur, on three sides.
January 4, 2010Alexia (age 10, az) Does the constelation of Cetus still exist today? Yes, it does! Visit our web page Cetus for information on this constellation.
January 4, 2010jahnavi.s (age 10, india) who gave the stars these strange names? Most of the names we use for the stars are Arabic, Egyptian or Greek in origin, and are often tied to mythology. They generally originate from ancient times.
December 30, 2009Hunter (age 11, canada) what is the smallest star in the scorpius constellation ? The faintest star in Scorpius (so far detected) is OGLE-2007-BLG-368. It is located at least 19 200 light years away from Sun. This star has mass 0.65 solar masses which implies that it could probably be a late K-type star.
October 6, 2009siti hajar binti zulkifli (age 11, malaysia) why the stars only can be seen at night? They are there, in the sky, but because the Sun is so bright we can't see them. During total eclipses of the Sun they reappear in the middle of the day. It is a beautiful sight!
September 28, 2009Mike (age 61, New Zealand) If the CRUX points SOUTH, is it influenced by Magnetic North? I don't believe so. Constellations are formed of bright stars which appear close to each other on the sky, but are really far apart in space. The shapes you see all depend on your point of view.
September 17, 2009Kaysie (age 20, Arizona) how does the change in seasons affects the motion of the stars. The apparent motion of the stars is affected by the relative position of the observer, which changes from season to season. The following web pages offer more information about the change in position for the main constellations and its causes: As the World Turn The Changing Night Sky Northern Summer and Southern Winter Constellations Exploring the Southern Hemisphere Constellations Exploring the Northern Hemisphere Constellations
August 19, 2009Randall (age 72, Florida) How much larger is the planet Antares than Earth? Antares is not a planet, it is a red supergiant star in the Milky Way galaxy and the sixteenth brightest star in the nighttime sky. Its radius is 800 times the radius of our Sun!!!
August 19, 2009Grace (age 13, California) How far from Earth is Girtab (a star that forms the constellation Scorpius, also known as Scorpio)? Girtab distance to Earth is about 272 light years.
August 19, 2009Grace (age 13, California) How far from Earth is Jabbah? Jabbah distance from Earth is about 435 lightyears.
August 19, 2009Grace (age 13, California) How far from Earth is Shaula, a star that forms the constellation Scorpius? It has been recently determined that Shaula is "just" 365 16 light-years from Earth.
July 20, 2009princess (age 13, mississippi,u.s.a) who discovered the costallation libra? Constellations are formed of bright stars which appear close to each other on the sky, but are really far apart in space. The shapes you see all depend on your point of view. Many societies saw patterns among the stars with gods and goddesses or stories from their culture. Constellations don't have a particular finder associated with them.
July 20, 2009Jim (age 13, Ohio) Isn't Ophucius a Zodiac constellation. It meets all classifications. Is it omitted because of the "unlucky thirteen" phenomenon? The fact is that there are only 12 recognized Zodiac constellations, but it is also true that the ecliptic itself passes through an additional thirteenth constellation, Ophiuchus, situated between Scorpius and Sagittarius.
July 17, 2009princess (age 13, mississippi,u.s.a) who discovered the costallation libra? Constellations are formed of bright stars which appear close to each other on the sky, but are really far apart in space. The shapes you see all depend on your point of view. Many societies saw patterns among the stars with gods and goddesses or stories from their culture. Constellations don't have a particular finder associated with them.
July 17, 2009Jim (age 13, Ohio) Isn't Ophucius a Zodiac constellation. It meets all classifications. Is it omitted because of the "unlucky thirteen" phenomenon? The fact is that there are only 12 recognized Zodiac constellations, but it is also true that the ecliptic itself passes through an additional thirteenth constellation, Ophiuchus, situated between Scorpius and Sagittarius.
July 16, 2009deja (age 12, wisonsin) what are the celestial objects in the constellation capricorn???? Capricorn has several galaxies and clusters. Messier 30 is a globular cluster located 1 degree south of the galaxy group NGC 7103. The constellation also harbors the wide spiral galaxy NGC 6907.
June 2, 2009Tyler (age 12, Deer Lodge MT) What can you tell me about draco the dragon? Draco the dragon is a circumpolar constellation. It can be seen all year round in the Northern Hemisphere. It is not visible in the Southern Hemisphere. Much more information on our web page Draco the Dragon.
May 29, 2009Abby (age 10, indiana) what is the distance between earth and cetus the constellation? Constellation are formed by stars and grooup of stars that can be at very differentdistances from our system. There are many galaxies in the Cetus constellation. One of them, M77 (NGC1068) is at 46.9 million light years.
April 28, 2009Ally (age 15, Michigan, USA) What other constellations are by Scorpius? Sagittarius is relatively closed to Scorpius.
April 17, 2009Aaron (age 12, Philippines) how does a constellation form? The shape of the constellations is more cultural that scientific. Constellations are formed of bright stars which appear close to each other on the sky, but are really far apart in space. The shapes you see all depend on your point of view. Many societies saw patterns among the stars with gods and goddesses or stories from their culture. Please, visit our web page Constellations and links therein for more information.
April 15, 2009Sandy (age 50, PA/USA) How is the Balmer thermometer used to determine the spectral class of a star? The Balmer thermometer is based on the fact that the star photosphere's temperature is reflected in the strength and variety of absorption lines in the spectrum. The Balmer lines (hydrogen spectrum lines in the visible) reach peak strength at a temperature of 10,000 K. These peaks arise from transitions of the electron upward out of the second energy level (second orbit). This relation is what is called the 'Balmer thermometer', which, along spectral information for other atoms, help scientists to determine the star temperature and spectral class.
April 14, 2009alyana (age 12, philippines) Is Betelguese a red giant star or a red supergiant star? Betelgeuse is a red supergiant, relatively luminous, and one of the largest stars known.
March 11, 2009Bobby (age 29, NM) Which very small constellation contains the most distant globular star cluster in the Milky Way galaxy? I am not sure if this is the right answer to your question, but I believe the farthest "cluster" of named stars inside a spherical (gravitationally influenced) Milky Way Galaxy, is the globular cluster NGC 2419 in Lynx.
March 3, 2009Gwyn (age 15, Massachusetts) I need to make a diagram of the constellation Camelopardalis. I cannot find any information on how it looks, how many stars there are in the constellation, and how many light years each of the stars are away. Can you please tell me? All the information you need can be found here and here.
March 3, 2009Gwyn (age 15, Massachusetts) I need to make a diagram of the constellation Camelopardalis. I cannot find any information on how it looks, how many stars there are in the constellation, and how many light years each of the stars are away. Can you please tell me? All the infrmation you need can be found here and here.
February 25, 2009joseph (age 67, georgia/usa) because a blue star is much hotter than our sun would it's core consist of plasma or another form of matter Although blue stars are indeed much hotter than the Sun, both types, and in fact all stars, are made of plasma. In fact, plasmas are by far the most common phase of matter in the universe, both by mass and by volume.
February 20, 2009Jonathan (age 14, Texas) Does a star get colder as its life progresses? There are, at different stages of stellar evolution, changes in temperature. Over long periods of time the changes can be quite radical (both increasing and decreasing temperature).
February 2, 2009jason (age 11, NJ?USA) How do we see the constellation Cygnus during this month but not the constellation Sagittarius? There are constellations that are visible all year-round. They are called circumpolar. For example, see the The Northern Circumpolar Sky and The Southern Circumpolar Sky. Other constellations rise and set along the year.
January 22, 2009Carly (age 10, California) What is Orion's Belt? I could be related with what is known as "The Three Kings," part of the Orion constellation. Alnitak, Alnilam, and Mintaka make up the asterism known as "Orion's Belt," the three bright stars in a row.
January 22, 2009Carly (age 10, California) What is Orion's Belt? I could be related with what is known as "The Three Kings," part of the Orion constellation. Ori (Alnitak), Ori (Alnilam), and Ori (Mintaka) make up the asterism known as "Orion's Belt," the three bright stars in a row.
November 6, 2008Amber (age 21, MI/ USA) What major constellation is seen in Michigan but not in Bolivia? Our web page The Northern Circumpolar Sky shows that Cassiopeia, Cepheus, Draco, Ursa Major, and Ursa Minor are all North Hemisphere constellations.
November 4, 2008Alison (age 8, Charlotte, NC) What happens to one of our constellations, if one of it's stars die? Especially one of the major ones like our astrology signs. Nothing would happen. Constellations are just formed of bright stars which appear close to each other on the sky, but are really far apart in space. The shapes you see all depend on your point of view.
October 10, 2008Valerie (age No, Canada) Does the zodiac sign Aries have a constellation and myth?
Thank you!
There are a couple of myths about Aries. It is said that when Bacchus and his friends were lost in the desert, they were rescued by a ram. As a reward Bacchus put the ram in the stars. See this page for more information.
September 16, 2008Jeff (age 47, Florida) How can I find the constellations that would be most prevalent in Grand Cayman August 10-17,2008. I want to be able to identify them.THX Our website offers pictures and descriptions of the Northern Hemisphere constellations, Southern Hemisphere constellations, and Sky Maps for several locations.
September 15, 2008mohd (age 9, singapore) what constellation is v shaped The SCULPTOR constellation shape is very close to a V. See this map.
September 12, 2008Kyle (age 12, Philippines) What are the color and magnitude of stars in hercules constellation? Here is a table of notable stars in the constellation Hercules, sorted by decreasing brightness.
September 12, 2008Zita (age 17, Serbia) Is there any offical shape of the constellations? (if it is, where can I find it) I mean I found eleven kind of shape for the Lion with the same stars(or more)... Is it O.K. that everybody sees it other way? Constellations are formed of bright stars which appear close to each other on the sky, but are really far apart in space. The shapes you see all depend on your point of view. Many societies saw patterns among the stars with gods and goddesses or stories from their culture. PLease, visit our web page Constellations and links therein for more information.
September 12, 2008Zita (age 17, Serbia) Is there any offical shape of the constellations? (if it is, where can I find it) I mean I found eleven kind of shape for the Lion with the same stars(or more)... Is it O.K. that everybody sees it other way? The shape of the constellations is more cultural that scientific. Constellations are formed of bright stars which appear close to each other on the sky, but are really far apart in space. The shapes you see all depend on your point of view. Many societies saw patterns among the stars with gods and goddesses or stories from their culture. PLease, visit our web page Constellations and links therein for more information.
September 4, 2008Antoinette (age 18, Florida/United States) What object was used to observe the supernova in 1987 The SN1987A was observed from space, on March 4-12, 1987, by Astron, the largest ultraviolet space telescope of that time.
August 25, 2008Amy (age 13, qld) what ancient civilisations used the constellions as a way of life and can you please explain how the stars influenced there lives?? Almost all ancient civilizations developed myths around the shapes they saw formed by the stars. PLease, see our page Constellations and links therein for more details on this topic.
August 21, 2008Elizabeth (age 14, Texas) How far is the constellation Leo from earth? When talking about a constellation an exact distance is always hard to detrmine because constellation are formed of bright stars which appear close to each other on the sky, but are really far apart in space.
August 18, 2008Eilish (age 12, Texas, USA) At what time (cst) is the taurus constellation visible? Taurus is clearly visible in the Northern Hemisphere winter sky, between Aries to the west and Gemini to the east. It is best seen in January, at 9:00 PM.
August 15, 2008Jordan (age 14, New York) How does the position of a particular star vary from night to night in a 2 month period of time? Not enough to be detectable. It has been calculated that the position of a given stars varies at a rate of one degree in 72 years.
June 23, 2008joseph (age 9, Texas/USA) When was Aquarius discovered and who named it? Constellations are formed of bright stars which appear close to each other on the sky, but are really far apart in space. The shapes you see all depend on your point of view. Many ancient societies saw patterns among the stars with gods and goddesses or stories from their culture. More related information on this particula constellation in our web page Aquarius.
May 16, 2008nicole (age 11, philippine) can you please list down all the constellation in Northern and
Southern Hemesphere?
That would be a long list, we have compiled the information you want in our web pages Northern Hemisphere Constellations and Southern Hemisphere Constellations.
April 24, 2008Biarki (age 12, B.C. Canada) What is the legend of Leo the Lion. More than two thousand years ago, Greeks believed the god Zeus placed the figure of a gigantic lion in the sky with the rest of the stars. This lion lived in the city of Nemea. The people who lived in that region were terrorized by the Nemean Lion. Several times they tried to destroy the beast. Heracles, the most famous Greek hero, was ordered by the king, Euryshtheus, to kill the Nemean lion. Heracles was an incredibly strong man. The Romans called him Hercules. When Heracles reached the cave where the beast was living, he realized all his weapons were useless against the lion. Heracles killed the lion by strangling it with his bare hands. When the beast was dead, Heracles used its pelt as a coat and the head as a helmet.
March 27, 2008grace (age 10, missouri) what is the apparent cause of the movement of the stars? The different orbital positions of the Earth throughout the year cause us to view changes on the relative positions of the stars.
March 24, 2008Briana (age 12, Colorado) Is a Supernova hotter than the Sun? In a typical Type II supernova, the newly formed neutron core has an initial temperature of about 100 billion kelvins (100 GK); 6000 times the temperature of the sun's core. More information here.
March 20, 2008dwight (age 11, philippines) what are the 9 stars that constellate leo? Some of Leo's stars are Regulus, Leo, Denebola, Leo, Leo, Leo, Leo, Leo, Leo.
March 18, 2008john (age , ) In our web page Star Statistics you can find the distance to the nearest stars.
March 17, 2008vijaya (age 35, india) when we look at sky at night in winter season from the northern hemisphere ,we will see the constellation ORION,suppose if we want to look at day may be at the time of total solar eclipse ,then what can we see at day time because its dark from the ecclipse ,also what constellation we can see that time. If I understood your question, you should be able to see the constellation Scorpius.
March 3, 2008shandi (age 10, indianapolis,indiana) how many miles away from Earth is Cygnus the star?
thanks for answering my ?
The distance from our system to Cygnus X-1 is about 2500 parsecs or 8000 light years.
March 3, 2008stephanie (age 13, connetitcut) is venus the north star Venus is known as the morning and the evening star. The North Star (also known as the Pole Star) is the star that lies closest in the sky to the north celestial pole, currently Polaris.
February 15, 2008Grace (Northwood, NH) Who discovered the constellation Cepheus? Cepheus has been known since ancient times by many civilizations. Visit our web page Kin Cepheus for more information.
February 15, 2008Grace(Northwood, NH) Who discovered the constellation Cepheus? Cepheus has been known since the ancient times by many civilizations. Visit our web page Kin Cepheus for more information.
February 8, 2008lajuanda (wisconsin) where do i find the constellation leo Leo is one of the constellations visible to people living north of the equator in Spring and to people living south of the equator in Autumn. Leo is visible from February through June. Cancer sets to the east and Virgo is to the west. Hydra and Crater are below.
February 4, 2008Erin (Michigan) What are the 6 main stars in the Horologium constellation? The six main stars of the Horologium constellation (sorted by decreasing brightness) are: Hor Hor Hor Hor Hor Hor
February 3, 2008Dorian (Indiana, USA) Are all stars in galaxies, and if not what do you call the ones that aren't??? (we thought we had found the answer in an article about a 'rogue star', but we can no long find the article or any mention of rogue stars) An example of a rogue star is Eta Carinae. This NASA web page offers information, links and a picture of this star.
January 30, 2008Sam ( U.S.A) what myths r there for the Little Dipper? Ursa Minor, also called the Little Dipper, is a circumpolar constellation. This means it never sets in the northern sky. The true figure represented by the stars is the Little Bear. Its counterpart is Ursa Major, or the Great Bear. There are several mythological stories behind these famous constellations. In Greek myth, Zeus was having an affair with the lovely Callisto. When his wife, Hera, found out she changed Callisto into a bear. Zeus put the bear in the sky along with the Little Bear, which is Callisto's son, Arcas. In other myths, the constellation is not a bear at all, but is in fact a dog. More information in our web page Ursa Minor (Little Bear).
January 15, 2008Regum (swindon/country) i am from west england and i would like to know which group of stars can be seen at autumn? You can see the main constellations observed from the North Hemisphere during each season in our web page Northern Constellations.
December 26, 2007Ashley (GA, Macon) what are stars mainly made out of? what fuel does it brun? The Sun, considered an average star, is mainly made of Hydrogen and Helium (70% Hydrogen, 28% Helium, 2% other gases).
December 26, 2007Lizzy (Canada / Vancouver) How do stars twinckle and shine? The movement of air in the atmosphere of Earth causes the starlight to bent as it travels from the star through the atmosphere to us. Some of the light reaches us directly and some gets bent, and to our eyes, this makes the star seem to twinkle.
December 26, 2007christopher (philippines) what is the smallest star? The smallest known star is OGLE-TR-122b. This article offers more information about this star.
December 19, 2007Jenna(Maryland, United States) How far away is the Andromeda Galaxy from the Milky Way? The Andromeda galaxy is about 2.9 million light years away from us. 1 light year = 9 460 528 400 000 kilometers.
December 17, 2007Yan (Malta) Since the Sun is a Star, is it true that all stars are suns? Yes, the Sun is just an average star. There bigger stars, and smaller stars. Visit our page Stars for more information.
December 10, 2007Matthew (GA, USA) How far is Perseus from earth? The brightest star of Perseus is Per (Mirfak). Mirfak is at a distance of around 590 light-years from our system.
October 16, 2007veena (india) why the 'neutron star' has only 'neutron particle'? That statement is not exactly true. The matter at the surface of a neutron star is composed of ordinary atomic nuclei as well as electrons. As we proceed inward, we will encounter nuclei with ever increasing numbers of neutrons; such nuclei would quickly decay on Earth, but are kept stable by tremendous pressures.
October 16, 2007Conrad Our web page Constellations offers a wealth of information, including some celestial maps.
September 25, 2007sara ( uk) is it true that when you look at stars your seeing them as much as a billion years ago? In general, we are able to see the stars and other celestial bodies due to the light they emit. The speed of light, althoug a very high value (around 300 000 000 meter per second), is finite; and considering the distance to the stars, the light takes a certain amount of time to reach our planet. A couple of examples. The closest star to our system is Proxima Centauri, at a distance of 4.2 light years. This means that the ligth from Proxima Centauri takes 4.2 years to reach us. The Andromeda Galaxy, on the other hand, is approximately 2.5 megalight-years away, this is, light from this galaxy takes 2.5 million years to reach us!
September 17, 2007Rebekah (Victoria) How many constellations are there in the southern hemisphere? Our page Exploring the Southern Hemisphere Constellations list the constellations for each season of the year.
September 12, 2007William (Georgia) What are the four circumpolar constellations of North Carolina? Asuming a latitud of 350N, the circumpolar constellations are: Ursa Major, the Big Bear (includes the Big Dipper); Ursa Minor, the Little Bear; Cassiopeia, the Queen of Ethiopia; Cepheus, the King of Ethiopia; Draco, the Dragon.
July 26, 2007Gary (ohio) Is there a point at the north pole where there is no stars? No, with a clear sky (no clouds) the view of the star should be magnificent (due to the low light contamination). This map offers te stars and constellations visible from the North Pole.
July 21, 2007Ryan (Philippines) What is the life cycle of a star in H - R diagram? Stars spend most of their life in the main sequence (while burning hydrogen and helium). Once a star has stopped burning hydrogen in its core, it begins to expand, and moves off the main sequence towards the upper right (the giant region). The more massive stars sit on the hotter portion of the main sequence, live shorter lives than the less massive stars, and become larger giants. Less massive stars sit on the cooler portion of the main sequence, live much longer lives, and may never become giant stars at all. Adapted from Hertzsprung Russell Diagram and Stellar Evolution.
July 20, 2007Shannon (California) I'm a Scorpio, I was wondering if I can see the scorpion constellation from my house and when can I see it? Scorpius is a Northern Summer Constellation. If you live in the northern hemisphere of the Earth, Scorpius crawls across the southern sky, close to the horizon. But if you live in the southern hemisphere, it passes high in the sky. More information about this costellation in our web page Scorpius.
July 20, 2007siddharth (uttar pradesh/india) How can a new star form from an old dead star in which all the hydrogen has been converted into Carbon or any other heavy element through a Supernova Explosion? This explosion happens because the center, or core, of the star collapses in less than a second. The outer layers of the star are blown off in the explosion, leaving a contracting core of the star after the supernova. The shock waves and material that fly out from the supernova can cause the formation of new stars. There are many beautiful images of supernova remnants, the expanding shell of gas made up of the outer layers of the original star. For more information, visit our web page Exploding Stars.
July 19, 2007radhika (india) can you please give me an information about zodiacal consetellation Constellations are formed of bright stars which appear close to each other on the sky, but are really far apart in space. The shapes you see all depend on your point of view. Many societies saw patterns among the stars with gods and goddesses or stories from their culture. More information in our web page Constellations and the links therein.
July 17, 2007ian (New York/United States of America) what is th brightness of a star as seen from Earth? The apparent magnitude of a star is a measure of its apparent brightness. The brightest stars that can be seen by the naked-eye are defined as first magnitude. Slightly fainter stars are called "second magnitude". This scale continues down to sixth magnitude, that are he faintest stars we can see (naked-eye) in very good conditions (no light pollution, no Moon). Extracted from Astrometry.
July 16, 2007roxann (ms.) how far is a star whose apparent magnitude is 12.7 and absolute magitude is 2.7 "Absolute" (M) and "apparent" (m) magnitudes are related by the expression: m = M - 5(log10 d - 1) where d is the distance. Using the provided values we obtained about 100 parsecs.
July 13, 2007sherianne (singapore) Are there such things twin stars Most stars are members of multiple-star systems. Some stars are members of close binary systems where material from one star swirls around the other in an accretion disk. More information at NASA.
July 11, 2007daniela (texas) who could you look for in the summer sky? This webpage shows the constellation that can be seen in the summer sky. Also look for Mars over the southern horizon and Venus, which shows up before dawn in the eastern sky.
July 10, 2007jim Yes, the Northern Cross can be seen from the northern hemisphere. This webpage will help you to locate it.
July 10, 2007jim Yes, the Northern Cross can be seen from the northern hemisphere. webpage will help you to locate it.
July 6, 2007Bianca (Texas) What are the names of the five main groups of stars? One way to group stars is: Supergiants, Bright giants, Normal giants, Sub giants, Main sequence, and Subdwarfs.
July 3, 2007sunitha (india) how does a star be born and die,do they reproduce? Visit NASA-Star Lifecycle for a detailed explanation of the lifecycle of stars.
July 2, 2007QooBlack how do stars reroduce? Visit NASA-Life Cycles of Stars for a detailed explanation of the cycle.
June 28, 2007hunter (florida) What are the main stars of cancer? The main stars in Cancer are Alpha, a; Beta b; Gamma g; Delta d; and Iota i.
June 28, 2007kayla ( illinois) how did the white dwRF GET ITS NAME We already know that medium mass stars, like our Sun, become red giants. But what happens after that? Our red giant Sun is still eating up helium and cranking out carbon. But when it's finished its helium, it isn't quite hot enough to be able to burn the carbon it created. What now? Since our Sun isn't hot enough to ignite the carbon it its core, it succumbs to gravity again. When the core of the star contracts, it causes a release of energy that makes the envelope of the star expand. Now the star has become an even bigger giant than before! Our Sun's radius has become larger than Earth's orbit! The Sun is not very stable at this point and loses mass. This continues until the star finally blows its outer layers off. The core of the star, however, remains intact, and becomses the white dwarf. Extracted from NASA/White Dwarfs.
May 23, 2007Lucy (Vic) In the foot of the Aquarius constellation, can you please name the star? It depends what do you mean by "foot". If you are refering to the lower part of the constellation, then it is 88 Aquarii. If you want to know the starts at the feet of the "water bearer", then they are Epsilon Aquarii (right foot) and Iota Aquarii (left foot).
May 10, 2007Jerky (Indonesia) What is the little dipper Ursa Minor, also called the Little Dipper, is a circumpolar constellation. This means it never sets in the northern sky. The true figure represented by the stars is the Little Bear. Its counterpart is Ursa Major, or the Great Bear. More information in our web page Ursa Minor.
May 10, 2007Ally (Idaho, United States) WHat are the main stars that are in the constellation Andromeda? Some of th notable stars in Andromeda are Alpha Andromedae (Alpheratz or Sirrah), Beta Andromedae (Mirach), Gamma Andromedae, Pi Andromedae, 56 Andromedae, R Andromedae, RX Andromedae, and Groombridge 34.
May 10, 2007victoria (florida) what ia the whole background of the constellation columba? Columba is a small constellation just south of Canis Major and Lepus; it was cut out of the constellation Canis Major by Augustin Royer, in 1679. Before being designated as a full constellation, Columba Noachi was already to be seen as an asterism in Bayers Uranometria of 1603. Adapted from Wiki/Columba.
May 5, 2007Brian (British Columbia) Why a cooler star could actually appear brighter than a hotter star? How bright a star looks when viewed from Earth depends on two factors: (1) the actual brightness of the star -- that is, the amount of light energy the star emits (sends out) -- and (2) the distance from Earth to the star. A nearby star that is actually dim can appear brighter than a distant star that is really extremely brilliant. For example, Alpha Centauri A seems to be slightly brighter than a star known as Rigel. But Alpha Centauri A emits only 1/100,000 as much light energy as Rigel. Alpha Centauri A seems brighter because it is only 1/325 as far from Earth as Rigel is -- 4.4 light-years for Alpha Centauri A, 1,400 light-years for Rigel. Adapted from NASA - Star.
May 5, 2007Josh For summer solstice conditions Crux would be closer to the equator, while for winter solstice would be farther.
April 19, 2007Faunce ( united states) what are the stars in hydra A complete list of the stars in Hydra can be found here.
April 19, 2007Emily (PA) What does the name corona borealis mean? Corona Borealis is a small northern constellation whose main stars form a semicircular arc. It has been known for a long time: Ptolemy included Corona Borealis as one of the 48 constellations listed by him.
April 13, 2007bella (va) I would like to know ALL of the names of the constellations, can you please tell me? I need to do the reserch about three of them. Thank you To list all of the constellations here would take too long and too much space, but you can visit the web page NASA-Constellations for a comprehensive list.
April 7, 2007sophia (New Zealand) how old is the contellation aquarius? Aquarius has been known since long ago. In Greek myth, Aquarius was Ganymede, the young boy kidnapped by Zeus. Zeus sent his eagle, Aquila, to snatch Ganymede out of the fields where the boy was watching over his sheep. Ganymede would become the cupbearer for the Olympian gods. The constellation, Crater, is often thought to be Ganymede's cup. The Sumerians also believed that Aquarius brought on a sort of global flood. Also, many of the stars that make up Aquarius have names that refer to good luck. This is most likely due to the time of year when the Sun would rise in Aquarius. It happened to be at the same time when the rainy season began in the Middle East. For more information about this constellation visit our web page Aquarius.
April 7, 2007stephen (ca. usa) whatis the size of the southern cross As with any other constellation, the size and proposrtions of the Southern Cross depend of the season and location of the observer.
March 31, 2007Davit (california) how do earh's rotation revolution affect the way we see stars? There are two important movements that affect the Earth: the rotation of the Earth around an invisible axis (one full rotation is completed in 24 hours), and its revolution around the Sun (one full revolution takes 365 days.) The first motion is responsible for days and nights, and the slow changes of the night sky.
March 27, 2007Laura (Colorado, USA) what machines or materials do you use to figure out the distance from different objects in space to Earth? There are currently no direct method to measure the distance to from Earth to stars and other objects very far away. Astronomers use the method of triangulation or parallax to obtain the distances to stars. This method is based on the known diameter of Earth's orbit (about 300 million kilometers). If we have two, six month apart, values of the viewing angle for a given star, it is relatively easy to obtain the distance with a little trigonometry. This technique works for stars within about 400 light years of our planet.
March 26, 2007amber (florida,usa) What is the total number of stars in the lyra constellation? The five most brilliant stars in Lyra are; Vega, Gamma Lyrae, Beta Lyrae, R Lyrae, and Delta2 Lyrae. For a complete list of stars in Lyra constellations, visit Wiki/Lyra.
March 21, 2007Vanamali (Karnataka, India) Sir,
Those stars with mass less than or eaqual to that of our sun, after the MAIN SEQUENCE stage enter the RED GAINT phase. What will be the fate of such stars afterr the RED GAINT phase?
A star with a mass similar to that of our Sun and in the last phase of its life is a red giant. Hydrogen fusion reactions have become less efficient in the core region, and the fusion reactions now occur in a shell surrounding the core. The outer layers then cool to about 3000 K and becomes a red star of a huge size. After a few more millions of years, the star evolves into a white dwarf-planetary nebula system.
February 28, 2007William (California United States) Please do in less than 4 days.what is a speical feature found on the consellation Scorpius Scorpius is a large constellation located in the southern hemisphere near the center of the Milky Way. Scorpius contains many bright stars and, due to its location on the Milky Way, also contains many deep sky objects such as the open clusters Messier 6 and Messier 7.
February 28, 2007Harry (Victoria) How big are galaxies? Using our Milky Way as an example: most of the stars in our galaxy are in a disk that is about 100 000 light years across in diameter and 3 000 light years thick. But keep in mind that most of the dozens of galaxies in our Local Group are at least ten times smaller in diameter.
February 28, 2007tim (wisconsin, u.s.) what are constellations, how are they made and what are there purpose Constellations are formed of bright stars which appear close to each other on the sky, but are really far apart in space. The shapes you see all depend on your point of view. Many societies saw patterns among the stars with gods and goddesses or stories from their culture.
February 28, 2007sean (Iowa) What are constellations for? Constellations are formed of bright stars which appear close to each other on the sky, but are really far apart in space. The shapes you see all depend on your point of view. Many societies saw patterns among the stars with gods and goddesses or stories from their culture.
February 28, 2007dakota (IL) what is a star constellation? Constellations are formed of bright stars which appear close to each other on the sky, but are really far apart in space. The shapes you see all depend on your point of view. Many societies saw patterns among the stars with gods and goddesses or stories from their culture.
February 28, 2007jan (loundon) what are the 12 contellations I believe you are asking about the constellations that are part of the Zodiac. They are: Aquarius, Pisces, Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, and Capricorn.
February 28, 2007Ruby (UAE) Why is it that the HD93129A, cannot be seen just like the Sun? While HD93129A is 120 times our Sun mass, and has a luminosity between 2 500 000 and 5 500 000 solar luminosities; it is also about 10,000-11,000 light years (1 light year = 9 460 730 472 580.8 km) distant. In comparison, our Sun is only around 150 000 000 km from our planet.
February 24, 2007BRITTANY (NC/USA) DO YOU HAVE A PICTURE OF ORION? Please, visit our web page Images of Orion.
February 20, 2007Brent (Canada) What is an old, cold star called? A white dwarf is an astronomical object produced when a star of low or medium mass dies.
February 13, 2007Jeremy (ohio,us) Is Aquarius close to the big dipper? No, thay are in different sectors of the sky. Ursa Major (The Big Dipper) is a Northern Circumpolar constellation, Aquarius is a Northern Autumn constellation.
February 13, 2007Allison ( New York) When were constellations first studied? Constellations are formed of bright stars which appear close to each other on the sky, but are really far apart in space. The shapes you see all depend on your point of view. Many ancient societies saw patterns among the stars with gods and goddesses or stories from their culture. More related information in our web page Constellations.
February 12, 2007kalyan (india) stars twinkle, from wherever we see them,i am sure ! why ? Stars twinkle (when seen from the Earth's surface) because we are viewing them through thick layers of moving air in the Earth's atmosphere. The scientific name for this phenomenon is stellar scintillation.
January 23, 2007Vipul (India) How is the end of a white dwarf? A white dwarf core has no further source of energy, and will gradually cool down and becomes extremely dense. The maximum mass of a white dwarf, beyond which degeneracy pressure can no longer support it, is about 1.4 solar masses. A white dwarf which approaches this limit (typically by mass transfer from a companion star), may explode via a process known as carbon detonation.
More information can be found at Wikipedia, and at our web page White Dwarfs.
January 23, 2007Vipul (India) How is the end of a white dwarf? A white dwarf core has no further source of energy, and will gradually cool down and becomes extremely dense. The maximum mass of a white dwarf, beyond which degeneracy pressure can no longer support it, is about 1.4 solar masses. A white dwarf which approaches this limit (typically by mass transfer from a companion star), may explode via a process known as carbon detonation. More information can be found at Wikipedia, and our web page White Dwarfs.
January 23, 2007kelsey (USA) What is the and and size relative to our sun of the star Kuma, from the constellation Draco? Kuma, also known by its Greek letter name Nu Draconis, is a double star (Nu-1 and Nu-2) . Both stars shine with about 9 times the luminosity of the Sun and have masses 1.7 times the mass of our Sun.
January 23, 2007vanessa (Illinois) what season does cepheus the constellation come out ? In the north hemisphere, depending of your latitude, Cepheus is one of the circumpolar constellations (permanently visible).
January 23, 2007Nathan (Canada) Why do stars form constellations? Constellations are formed of bright stars which appear close to each other on the sky, but are really far apart in space. The shapes you see all depend on your point of view. Many societies saw patterns among the stars with gods and goddesses or stories from their culture. Fore more information visit our web page Constellations.
January 21, 2007kierra (IN) what are the stars names in the scorpius? More than any other constellation, Scorpius resembles its given name. If you live in the northern hemisphere of the Earth, Scorpius crawls across the southern sky, close to the horizon. But if you live in the southern hemisphere, it passes high in the sky. The bright star Antares marks the heart of the arachnid, and its long curving tail trails to the south. Scorpius contains many bright stars, including Antares, Graffias, Dschubba, Sargas, Shaula, Jabbah, Grafias, Alniyat, and Lesath. For more information, please visit our web page Scorpius.
January 16, 2007devon (kansas) what is cetus The constellation Cetus represents the Sea Monster. It is one of the largest constellations known. In classical civilizations, the figure was the giant sea monster that almost ate Andromeda. More information on this constellation can be found in our web page ,Cetus.
January 16, 2007Emerson ( Australia) What are the names of the two stars that point to the Southern Cross?
Thank you.
Alpha Centauri and Beta Centauri are used to localize the Southern Cross (the Crux). If a line is drawn between them,is easy to find the top of the Crux. The two stars are often referred to as the "Pointer Stars" or "White Pointers".
January 5, 2007maria (usa) I need to know 5 facts about the constellation Aquarius please Aquarius is a member of the Zodiac, a group of constellations that the Sun travels through each year. It is best viewed in the fall in the southern sky, although much of the northern hemisphere can see the Waterbearer in the spring. Aquarius is one of the oldest constellations in the sky. Fore more information about this topic, please visit our web page Aquarius.
January 5, 2007summer (denison) how did we find out that was other plantes The motion of the planets in the sky is quite different from the stars. For example, stars move with a very low pace, while planets move faster. Planets also have what is called Retrograde Motion, a reversed motion through the stars relative to average yearly motion.
January 3, 2007bob (NZ) I am doing a school topic on an aspect of space.Can you please tell me some info on scorpius? Some constellations do not really look like their names. It takes a lot of imagination to picture the stars of Pegasus as a winged horse, for example. But Scorpius really looks like a scorpion! It has a long, curving tail, and snapping claws, just like the real arachnid. The bright star Antares marks the heart of the scorpion. For more information about this constellation, please visit our web page Scorpius.
December 20, 2006Yoomin (Ontario, Canada) I'm doing a project on the stars.
What is a neutron star?
Neutron Stars are the end point of a massive star's life. When a really massive star runs out of nuclear fuel in its core the core begins to collapse under gravity. When the core collapses the entire star collapses. The surface of the star falls down unti l it hits the now incredibly dense core. It then bounces off the core and blows apart in a supernova. All that remains is the collapsed core, a Neutron Star or sometimes a Black Ho le, if the star was really massive. More information can be foun at our web page Neutron Stars.
December 14, 2006rija (united states) i need information on the constellation canis major, what is canis major? The constellation Canis Major is known as the Great Dog. In Greek myth, it is said that this constellation, along with Canis Minor, are Orion's hunting dogs. Canis Major was one of the most important constellations in ancient times because the brightest star in the sky is part of it. For more information about this constellation, please visit our web page Canis Major
December 13, 2006Karina (New Mexico) How mant myths does Hydra have? For a description of Hydra myths, visit our page The Lernaean Hydra.
December 9, 2006kenedi (scotland) how did the big dipper help people when they were travelling? Ursa Major is full of unique celestial objects. Two of the stars, Dubhe and Merak, are pointer stars. If you are looking at the Big Dipper, the outer edge stars that make up the "bowl" of the dipper are the two stars, with Merak being the one on top. Connect a line between the two, and extend it north a distance about five times the distance between them. It will connect with the North Star, Polaris. More information can be found at our web page Ursa Major.
December 9, 2006Allen How are constillations made? Constellations are formed of bright stars which appear close to each other on the sky, but are really far apart in space. The shapes you see all depend on your point of view. Many societies saw patterns among the stars with gods and goddesses or stories from their culture. Fore more information visit our web page Constellations

Last modified October 14, 2003 by Jennifer Bergman.

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