A star which of the following apparent magnitudes appear brightest from Earth?
E---- the bigger the POSITIVE number the dimmer the star
If 2 stars have the same magnitude, why does one appear brighter?
It is likely the magnitude is being expressed as absolute magnitude, as opposed to apparent magnitude. Apparent magnitude is how bright the star appears to the observer. Quite often apparent magnitude measurements are done with the naked eye (as opposed to uisng instruments). For this reason a star that appears to be brighter won’t be given the same magnitude as a dimmer star.Absolute magnitude is a measurement of the brightness of a star if it were 10 parsecs (32 ly) from earth. This scale was created so that we could compare apples to apples when asertaining the actual brightness of stars relative to each othger. For example, two stars at 10 parsecs are at magnitude 6M (by convention absolute magnitude is represented by M and apparent magnitude by m). However, neither star is actually 10 parsecs distance. One may actually be 20 lightyears distant and the other may be 40 lightyears. Since both stars are equal in brightness, the one that is 40 lightyears away would have an apparent magnitude of 6.44m andthe star that is only 20 lightyears away would have an apparent magnitude of 4.93m causing the closer star to appear brighter.If one of the stars is a variable it will often be catalogued with a magnitude range such as 5.5–6m. Once in while a star that was thought to have a stable luminosity might actually prove to be otherwise, in which case follow measurements may modify the catalogue magnitude value.
Why is the absolute magnitude of some stars greater than their apparent magnitude?
That is the case for most stars. They are a long way away. It is the brightness of a star as it would appear if it were 10 parsecs (32.6) light years away. So stars at that distance would have equal absolute magnitude and apparent magnitude. Less than that distance, apparent magnitude is greater. And further than 10 parsecs, Absolute magnitude is brighter.
What is the apparent and absolute magnitude of a star?
Absolute magnitude is a concept that was invented after apparent magnitude when astronomers needed a way to compare the intrinsic, or absolute brightness of celestial objects.The apparent magnitude of an object only tells us how bright an object appears from Earth. It does not tell us how bright the object is compared to other objects in the universe. For example, from Earth the planet Venus appears brighter than any star in the sky. However, Venus is really much less bright than stars, it is just very close to us. Conversely, an object that appears very faint from Earth, may actually be very bright, but very far away.Absolute magnitude is defined to be the apparent magnitude an object would have if it were located at a distance of 10 parsecs. So for example, the apparent magnitude of the Sun is -26.7 and is the brightest celestial object we can see from Earth. However, if the Sun were 10 parsecs away, its apparent magnitude would be +4.7, only about as bright as Ganymede appears to us on Earth.
Question about absolute and apparent magnitude, please help. (No mathematics required)?
The absolute magnitude of star X (2) is brighter than its apparent magnitude (9), meaning it is greater than 10 parsecs from earth. Star Y's absolute magnitude, on the other hand, is fainter than its apparent magnitude, placing it less than 10 parsecs from earth. X is further from the earth than Y, so the answer is (d). In more general terms, the relative distances of a group of stars can be determined by subtracting the absolute magnitude from the apparent magnitude. The larger the answer, the further the star. For your example, star X has a magnitude difference of 9 - 2 = 7, while the figures for star Y are 4 - 6 = -2. Since 7 > -2, X is more distant than Y. Any effect that spectral type has on magnitude can be eliminated by using bolometric magnitudes, which indicate an object's total radiation in all wavelengths, as opposed to color magnitudes, which are determined at a specific wavelength of light.
Apparent and Absolute Magnitudes?
exactly correct. Absolute Magnitude is a standard. "Just how bright would that star be in the night sky IF it was 10 Parsecs away?" Apparent Magnitude is a measure of what we see. A star with an Absolute Magnitude of -2 would be VERY bright 10 pc away, and still visible many times that farther. Most red dwarf stars have an Absolute Magnitude of less than 5.5... and since MOST stars are red dwarfs... that implies that we can't see MOST stars farther away than 10pc. hmmmpf... i feel cheated.
Star A appears brighter than star B, as seen from Earth. Therefore, star A must be closer to Earth than star B?
False Stars B may be brighter in absolute magnitude. Stars A also may be bigger which is why it appears brighter, they may be the same distance from the Earth.
Apparent Magnitude vs Absolute Magnitude?
Stars are classified into magnitudes, according to their brightness as we see them. Stars of magnitude 1 are about 2½ times as bright as those of magnitude 2; those of magnitude 2 are 2½ times as bright as those of magnitude 3, and so on for each of the magnitudes. Stars of magnitude 6 are the faintest stars we can see with the naked eye. How bright a star looks depends on two thing: (1) how much light it radiates and (2) how far away it is. In Absolute Magnitude, this is considered the true brightness of a star at a set distance of 10 parsecs. (32.6 light years away) The distance of 10 parsecs is a constant distance that is set and never changes. So what this means is that if you were 10 parsecs away from a number of stars, you would know the Absolute Magnitude of each star regardless of how far away the really are from you. Apparent Magnitude is the brightness of a star and it all depends on how far you are from it. With Apparent Magnitude, there is no constant distance. For example, One particular star, Sirius, is twice as bright as Canopus. Actually, Canopus gives off 65 times as much light as Sirius. But Canopus is 100 light-years away, and Sirius is less than 9 light-years away. But regardless of size, Sirius would have a greater Apparent Magnitude than Canopus. If it helps, use this formula to find the distance when the Absolute and Apparent Magnitudes are known: 10^m-M+5/5 = distance m=apparent magnitude M=absolute magnitude You can also use this formula to find the absolute magnitude when the distance is known: M = m + 5 - 5 log (d)
What is the difference between apparent magnitude and absolute magnitude?
Apparent Magnitude is the star's brightness as it appears from earth. absolute magnitude is the apparent brightness of a star if viewed from a distance of 32.6 light years away.