Sentences with phrase «bright emission lines»

Not exact matches

More accurate distances between the most common type of «planetary nebulae» and the Earth can be estimated simply with three sets of data: firstly, the size of the object on the sky taken from the latest high resolution surveys; secondly, an accurate measurement of how bright the object is in the red hydrogen - alpha emission line; and thirdly, an estimate of the dimming toward the nebula caused by so called interstellar - reddening.

We have found that the spatial distribution of this emission does not coincide with the spatial distribution of the bright collision lines.

Three images, left to right, of the same thundercloud depict a less - than -10-milliseconds-long sequence of events: (left) formation within the cloud of a small channel, or «leader,» of electrical conductivity (yellow line) with weak emission of radio signals (ripples), to (middle) a burst of both dark lightning (pink) and radio waves (larger ripples), to (right) a discharge of bright lightning and more radio waves.

A Seyfert galaxy is a spiral galaxy with a compact, very bright nucleus that produces a non-thermal continuous spectrum with broad (fat) emission lines on top.

Even though most of the visible radiation is concentrated in a few discrete emission lines, the total apparent brightness of the brightest is the equivalent of tens of thousands of solar luminosities.

Previously classed as spectral type M4.5 e (with emission lines), the object was observed to be four times brighter than would be expected for a dim red dwarf of that type based on a revised parallax measurement of its distance from the Solar System (Ken Croswell, Science@Now, September 6, 2011).

A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from emission or absorption of light in a narrow frequency range, compared with the nearby frequencies.

Some environmental groups are starting to soften their blanket opposition to nuclear power as an option for cutting coal use and emissions, but most still maintain that bright line in the sand.

After all, many climate advocates have variously selected 350 PPM or 1.5 °C as their «bright line» goal (outcomes we've long since overshot), and yet the core calculus for these advocates is again the same: we must nonetheless still strive to reduce emissions as quickly as possible.

Those nice Balmer spectra and the like from Mercury vapor lamps or Sodium lamps and the like are observed in VERY LOW DENSITY gases, where the mean time between molecular or atomic collisions is much longer than the lifetimes of the excited states, so that spontaneous emission can occur; only then do you get the bright line spectra as seen in those HOT gases.