가지다. A모드(Amplitude, 진폭)는 초음파가 반사된 시간과 강도를 파형으로 표시한다. B모드(Brightness, 밝기)는 초음파의 강도에 따라 밝기가 다르게 보이는 방식으로 대부분의 복부초음파장치가 이런 방법을 사용한다. M모드(Motion, 운동)는 B모드 영상을 일정한 속도로 이동시키는 방식으로 심장처럼 ...
에서 UIT로 주로 관측한 대상은 M13 구상성단 외에 대마젤란은하 M31 M33 M101 LSB(Low Surface Brightness) 은하 등이다.이번 호에서는 아스트로1과 아스트로2가 촬영한 UIT 사진 가운데서 몇가지를 골라 봤다. 우리가 늘 봐왔던 눈에 익은 천체들이 자외선의 눈으로 어떻게 보일지, 그리고 여기에는 어떤 ...
촬영했다. UIT의 주 관측대상에는 M13 및 대마젤란은하, M31 M33 M101 외에 LSB은하(Low Surface Brightness galaxies:표면밝기가 어두운 은하) 등이 포함되었다. 노출시간은 아스트로1의 6백초 보다 훨씬 긴 2천초로 선택했다. 사이언스팀은 망원경의 넓은 시야를 이용, LSB 은하 외에 어두운 천체들까지 촬영할 수 ...
It could have been the kind of eruption in which young stars with unstable accretion disks can suddenly flare up in brightness. One star in that area, called FU Orionis, flared in 1936 and is still bright. Allen and Burton say that the other possible explanation for the explosion is a supernova deep within the molecular cloud in the Orion Nebula.Other astronomers have looked into Orion and ...
to be a galaxy's brightness and size. In the past, these studies have apparently come to erroneous conclusions about brightness and size because distance was not taken into account.Then there's the adventure of trying to find the reality that exists at the center of our Milky Way galaxy, shrouded in dust. Lately, astronomers are more certain that a black hole occupies the center. The question ...
t know.Asteroids also reflect infrared light that can be measured. That gives us two pieces of knowledge-the infrared brightness and the ordinary brightness. That, too, helps us decide how large an asteroid might be and how much light it reflects.What about the shape of asteroids? Every once in a while, an asteroid passes in front of a star and for a few seconds the starlight disappears ...
These are stars that pulsate. She noted in 1904 that the longer the period of light variation, the greater the average brightness of the star. In 1912, Leavitt had worked out a method for determining the relative distances of various Cepheids.The Cepheids offered the first method of determining really vast distances and man's knowledge of the universe was greatly enlarged as a consequence. It ...
are small stars and are of dim brightness.They are so small that they can only work up enough energy to have a surface brightness of 2,000 degrees-as compared with our sun's 5,700 degrees. These are "red dwarfs" and about three--quarters of all stars are red dwarfs.It is not at all likely that red dwarfs can support life. For that you need a sun-like star, but only 10 percent of the stars in ...
소련의 코카사스에 있는 '특수 천체물리 관측소'는 외계문명의 존재를 알아내기 위한 실험을 시작하겠다고 발표했다. 이 관측소는 세계에 ... 덧붙였다. 따라서 코카사스 관측소는 MANIA(multi channel analyser of nanosecond variation in brightness)라고 불리우는 장비와 컴퓨터를 사용해 광파를 찾기로 했다 ...
large. The Schaefers report that it is four times as bright at some times than at others.Usually, a periodic change in brightness means that an astronomical object is turning and, as seen from a certain angle, is brighter than when seen from other angles.One reason for this is that the object may be irregular in shape. The asteroid Eros, for instance, which can come as close as 14 million ...
동아사이언스
디라이브러리
DS스토어
팝콘플래닛
