Video Experimental Relacionado
Updated: Apr 19, 2026
10:35
Bringing the Visible Universe into Focus with Robo-AO
Published on: February 12, 2013
20.3K
No hay polvo frío dentro del remanente de supernova Cassiopeia A
Oliver Krause1, Stephan M Birkmann, George H Rieke
1Steward Observatory, University of Arizona, 933 N Cherry Avenue, Tucson, Arizona 85721, USA. krause@as.arizona.edu
Nature
|December 4, 2004
Resumen
Los restos de supernovas como Cassiopeia A no producen grandes cantidades de polvo frío. La mayor parte del polvo previamente atribuido a este remanente en realidad se origina en nubes interestelares, desafiando las teorías de producción de polvo de supernova.
Área de la Ciencia:
- La astronomía es la astronomía.
- La astrofísica es la astrofísica.
- Estudios del polvo cósmico Estudios del polvo cósmico
Sus antecedentes:
- Observaciones anteriores sugirieron que las supernovas de tipo II, como Casiopea A, producen un polvo frío significativo.
- Se pensó que este polvo explicaba las grandes cantidades de polvo observadas en cuásares distantes dentro del universo temprano.
Objetivo del estudio:
- Reevaluar el origen del polvo frío atribuido al remanente de supernova Cassiopeia A.
- Para determinar si las supernovas de tipo II son una fuente significativa de polvo cósmico.
Principales métodos:
- Observaciones en el infrarrojo lejano.
- Observaciones de líneas moleculares.
Principales resultados:
- La mayoría de la emisión submilimétrica previamente vinculada a Casiopea A se origina en el polvo interestelar.
- Este polvo se encuentra en una nube molecular de primer plano, no dentro del remanente en sí.
Conclusiones:
- El Cassiopeia A remanente no es una fuente significativa de polvo frío.
- La hipótesis de que las supernovas de Tipo II producen copiosas cantidades de polvo no está respaldada por este caso, lo que desafía las explicaciones para el polvo del universo temprano.
Videos de Conceptos Relacionados
02:39Emission Spectra
79.7K
When solids, liquids, or condensed gases are heated sufficiently, they radiate some of the excess energy as light. Photons produced in this manner have a range of energies, and thereby produce a continuous spectrum in which an unbroken series of wavelengths is present.
79.7K
01:21Schwarzschild Radius and Event Horizon
3.1K
No object with a finite mass can travel faster than the speed of light in a vacuum. This fact has an interesting consequence in the domain of extremely high gravitational fields.
The minimum speed required to launch a projectile from the surface of an object to which it is gravitationally bound so that it eventually escapes the object’s gravitational field is called the escape velocity. The escape velocity is independent of the mass of the object. Merging the idea of escape...
The minimum speed required to launch a projectile from the surface of an object to which it is gravitationally bound so that it eventually escapes the object’s gravitational field is called the escape velocity. The escape velocity is independent of the mass of the object. Merging the idea of escape...
3.1K
01:10Detection of Black Holes
2.6K
Although black holes were theoretically postulated in the 1920s, they remained outside the domain of observational astronomy until the 1970s.
Their closest cousins are neutron stars, which are composed almost entirely of neutrons packed against each other, making them extremely dense. A neutron star has the same mass as the Sun but its diameter is only a few kilometers. Therefore, the escape velocity from their surface is close to the speed of light.
Not until the 1960s, when the first neutron...
Their closest cousins are neutron stars, which are composed almost entirely of neutrons packed against each other, making them extremely dense. A neutron star has the same mass as the Sun but its diameter is only a few kilometers. Therefore, the escape velocity from their surface is close to the speed of light.
Not until the 1960s, when the first neutron...
2.6K
01:27Atomic Spectroscopy: Effects of Temperature
1.2K
Atomization, converting samples into gas-phase atoms and ions, is essential for atomic spectroscopy. The flame temperature required for atomization affects the efficiency of the atomic spectroscopic methods by increasing the atomization efficiency and the relative population of the excited and ground states.
At thermal equilibrium, the relative populations of excited and ground state atoms can be estimated using the Maxwell–Boltzmann distribution. For example, an increase in temperature...
At thermal equilibrium, the relative populations of excited and ground state atoms can be estimated using the Maxwell–Boltzmann distribution. For example, an increase in temperature...
1.2K
01:20Atomic Emission Spectroscopy: Overview
4.5K
Atomic emission spectroscopy (AES) is an analytical technique used to determine the elemental composition of a sample by analyzing the light emitted from excited atoms. In AES, atoms in a sample are excited to higher energy levels by thermal energy from high-temperature sources, such as plasma, arcs, or sparks. When these excited atoms return to lower energy states, they emit light at specific wavelengths characteristic of each element. The resulting atomic emission spectrum, which consists of...
4.5K
01:30Atomic Emission Spectroscopy: Interference
784
In atomic emission spectroscopy (AES), high-temperature atomizers excite a broad range of elements and molecules that generate complex emissions from sources such as oxides, hydroxides, and flame combustion products in the flame or plasma. Several strategies can be employed to minimize spectral interferences caused by overlapping emission lines or bands. These include increasing instrument resolution, choosing alternative emission lines, optimally placing the detector in low-background regions,...
784