#emission spectrum

[whats-in-a-sentence]

Figure 4.20 shows the emission spectra for selected atoms.

"Chemistry" 2e - Blackman, A., Bottle, S., Schmid, S., Mocerino, M., Wille, U.

[strictlyastronomy]

The Best Meteor Shower of 2017 Peaks Tonight

Brave the cold and head out tonight to see what may well turn out to be the year’s best display of bright meteors: the Geminids! Little bits of dusty debris from the oddball ‘rock comet’ 3200 Phaeton slam into the upper atmosphere of our planet at some 35 km/s (79,000 miles per hour), leaving glowing trails that appear to ‘radiate’ away from the constellation Gemini (the small red cross in the figure above). Like train tracks converging in the distance, these bright trails are actually more or less parallel to each other, and their apparent origin at a common ‘vanishing point’ is an illusion. As they encounter our atmosphere at high speed, they are heated by friction with air molecules until they briefly glow at a temperature of several thousand degrees, being almost completely vaporized while still dozens of kilometers above the ground. The meteor debris is ionized, emitting bright colors with the characteristic fingerprints of their constituent atoms.

(AccuWeather graphic)

2017 is an especially good year for this meteor shower because it occurs within a few nights of new moon, so the meteors won’t compete with moonlight for attention. The best time to see Geminids is within about two hours of local midnight. Look high in the east, but let your gaze wander around, for the meteors will be seen anywhere over roughly half of the night sky. No optical aid is necessary to see them, and your eyes are best equipped for the task: many Geminids are as bright as the brightest stars in the sky. Under good conditions and a dark sky, expect to see around 50-75 meteors per hour. So stay up late, keep warm, and enjoy this celestial holiday show!

[spacetime1969]

I feel like atomic emission spectrums are a valid gender

Like come on, that's amazing

[whats-in-a-sentence]

The emission spectrum for atomic hydrogen, shown in figure 4.22, shows several sharp emission lines of high intensity. (...) Figure 4.22 shows the energy level diagram for hydrogen atoms; arrows represent some of the possible absorption and emission transitions.

"Chemistry" 2e - Blackman, A., Bottle, S., Schmid, S., Mocerino, M., Wille, U.

[earthspirit10]

30 Day Pride Challenge - Day #3

Something rainbow

An emission spectrum! More specifically, our sun’s emission spectrum. Thought it’d be neat to use this for day 3.

[k-star-holic]

Lee Sung-kyung, Oriental Mood Han Gak...Attractiveness Big Emission Spectrum

Source: k-star-holic.blogspot.com

[sociedadcientificajuvenil]

¿Sabías que cada átomo es capaz de emitir o absorber radiación electromagnética (luz)?

Esto sucede solo en algunas frecuencias características propias de cada uno de los diferentes elementos químicos. Si a un elemento en estado gaseoso se le aplica calor, sus átomos emiten radiación en ciertas frecuencias específicas del espectro visible (la luz que podemos ver), a lo que se le llama espectro de emisión, pero si al mismo elemento, también en estado gaseoso, le hacemos incidir radiación electromagnética, absorbe también esta radiación en las mismas frecuencias en las que emite cuando se estimula mediante calor, esto se conoce como espectro de absorción. Conociendo ya que el espectro tanto de emisión como de absorción, es característico de cada elemento como su firma personal, visualizar este espectro sirve para identificar cada uno de los elementos presentes en toda clase de objetos, desde una roca hasta estrellas de las que nos encontramos muy lejos. En la imagen: Espectro de emisión de los elementos

[scinote]

Question:

This is a question regarding the recording & classification of stellar spectra. The radiation from stars travels through millions of light years to reach us. Would not the gas and dust lying between us and the stars contribute to its own absorption lines, thereby distorting the original light?

Asked by lastordovician

Answer:

The light from a star is a byproduct of thermonuclear fusion of elements inside the star. The resulting electromagnetic radiation is unique to the elements being fused. This radiation gives rise to spectral lines that enable astrophysicists to predict the chemical makeup of the star.

In other words, the different elements in stars give off different wavelengths, or colors, of light. These colors can be rather beautiful, as the emission spectrum below shows.

[Image source]

The light that comes from dust and gases, however, does not contribute to the radiation. Dust and gases don’t actually produce light; they reflect it. This reflection weakens and affects the direction of light, but it does not affect the wavelength, or color, of the light. 

It's like our moon-- the moon doesn't produce light itself; instead, it reflects the light of the Sun. This reflection weakens the light, which is why we're able to look directly at the moon but not the Sun. It doesn't, however, change the color of the Sun.

So overall, the net effect that the dust and gas have on the emission/absorption spectra of stars, if any, is very small.

Answered by Olivia D., Expert Leader

Edited by Peggy K.