Video Experimental Relacionado
Updated: Jul 29, 2026
09:36
The Use of High-resolution Infrared Thermography (HRIT) for the Study of Ice Nucleation and Ice Propagation in Plants
Published on: May 8, 2015
Observaciones infrarrojas térmicas desde tierra del cometa Hale-Bopp (C/1995 O1) durante 1996
1Center for Radiophysics and Space Research, Cornell University, Ithaca, NY 14853, USA. hayward@astrosun.tn.cornell.edu
Science (New York, N.Y.)
|March 28, 1997
Resumen
Las primeras observaciones en infrarrojo térmico (IR) del cometa Hale-Bopp revelaron el desarrollo de estructuras de coma de polvo y olivino cristalino. Estos hallazgos proporcionan información sobre la actividad cometaria meses antes del perihelio.
Área de la Ciencia:
- Ciencia de los Cometas Ciencia de los Cometas
- Astronomía por infrarrojos Astronomía por infrarrojos
- Ciencias planetarias Ciencias planetarias.
Sus antecedentes:
- El cometa Hale-Bopp (C/1995 O1) es un cometa periódico significativo.
- Comprender el desarrollo del polvo cometario es crucial para la ciencia planetaria.
Objetivo del estudio:
- Para rastrear el desarrollo del coma de polvo del cometa Hale-Bopp antes del perihelio.
- Para analizar las emisiones infrarrojas térmicas y las características espectrales.
Principales métodos:
- Utilizó imágenes térmicas infrarrojas (IR) y espectroscopia.
- Datos recogidos en junio, agosto y septiembre de 1996.
Principales resultados:
- Variaciones nocturnas observadas en el brillo del coma interno y un chorro hacia el norte a principios de junio.
- Documentó un aumento de 8 veces en el flujo de IR central de junio a septiembre.
- Identificó chorros de infrarrojos que se correlacionan con estructuras visibles y una fuerte característica de emisión de silicatos, incluida la olivina cristalina, a 4,1 UA.
Conclusiones:
- Las observaciones térmicas de infrarrojos rastrearon efectivamente el desarrollo del coma de polvo cometario.
- La presencia de olivina cristalina a 4,1 UA sugiere procesos de formación temprana.
Videos de Conceptos Relacionados
01:09Infrared (IR) Spectroscopy: Overview
When electromagnetic radiation passes through a material, atoms or molecules transition from a lower to a higher energy state by absorbing radiation corresponding to the energy difference between the two states. The absorption of infrared (IR) radiation causes transitions between vibrational energy levels in a molecule. Therefore, IR spectroscopy is a useful analytical tool for determining the molecular structure of molecules.
Different compounds display unique properties due to their...
Different compounds display unique properties due to their...
01:23IR Spectrum Peak Broadening: Hydrogen Bonding
The vibrational frequency of a bond is directly proportional to its bond strength. As a result, stronger bonds vibrate at higher frequencies, while weaker bonds vibrate at lower frequencies. The stretching vibration of the strong O–H bond in alcohols and phenols (very dilute solution or gas phase) appears as a sharp peak at 3600–3650 cm−1.
However, the extent of hydrogen bonding influences the observed stretching frequency and band broadening. Intermolecular or intramolecular hydrogen bonding...
However, the extent of hydrogen bonding influences the observed stretching frequency and band broadening. Intermolecular or intramolecular hydrogen bonding...
01:25IR Spectrometers
There are two main infrared (IR) spectrophotometers: dispersive IR spectrometers and Fourier transform infrared (FTIR) spectrometers. In a dispersive IR spectrometer, a beam of infrared radiation produced by a hot wire is divided into two parallel equal-intensity beams using mirrors. One beam passes through the sample, while another is a reference beam. The beams then move through the monochromator, which separates the radiations into a continuous spectrum of different frequencies. The...
01:20IR Spectrum Peak Intensity: Dipole Moment
The dipole moment of a bond is the product of the partial charge on either atom and the distance between them. Dipole moments influence the efficiency of IR absorption and the peak intensity. When a bond with a dipole moment is placed in an electric field, the direction of the field determines if the bond is compressed or stretched. Electromagnetic radiation consists of an electric field component that rapidly reverses direction. It follows that polar bonds are alternately stretched and...
01:02Flame Photometry: Overview
Flame photometry, also known as flame emission spectrometry, is a technique used for the qualitative and quantitative analysis of elements present in a sample using a flame as the source of excitation energy. The concept of flame photometry was realized in the early 1860s by Kirchhoff and Bunsen, who discovered that specific elements emit characteristic radiation when excited in flames. The first instrument developed for this purpose was used to measure sodium (Na) in plant ash using a Bunsen...
01:16Flame Photometry: Lab
In a flame photometer, when a solution like potassium chloride is aspirated into the flame, the solvent evaporates, leaving behind dehydrated salt. This salt dissociates into free gaseous atoms in their ground state. Some of these atoms absorb energy from the flame, leading to their excitation. The excited atoms return to the ground state, emitting photons at characteristic wavelengths. Because only electronic transitions are involved, the resulting emission lines are very narrow. The intensity...