Posted on Sep 20, 2020
APOD: 2020 September 20 - Breaking Distant Light
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Good morning, Rallypoint. Today's Astronomy Picture of the Day (APOD) is titled "Breaking Distant Light." Our featured image from the Visible MultiObject Spectrograph (VIMOS) operating at the Very Large Telescope (VLT) array in Chile takes light from distant galaxies and breaks it into its constituent colors (spectra). This allows astronomers to measure the redshift of known spectral lines and estimate how far away the galaxies are from Earth.
What is redshift? And what does it have to do with distance? Recall the Doppler effect, where the pitch of a sound seems to get lower and lower the further away its source is from your vantage point (think train whistle). Over cosmological distances, light behaves the same way. Based on the extent that spectral lines shift toward infrared (e.g. redshift), astronomers have a means to determine how far away a light source is based on a known formula.
So while many of the galactic spectral lines in today's APOD look similar, there are slight differences in each of them. This not only indicates how far each galaxy is from Earth, but also provides an idea of their predominant composition (e.g. hydrogen, nitrogen, oxygen, iron, etc). Analyzing the space distribution of distant objects will allow insight into when and how stars and galaxies formed, clustered, and evolved in the early universe.
What is redshift? And what does it have to do with distance? Recall the Doppler effect, where the pitch of a sound seems to get lower and lower the further away its source is from your vantage point (think train whistle). Over cosmological distances, light behaves the same way. Based on the extent that spectral lines shift toward infrared (e.g. redshift), astronomers have a means to determine how far away a light source is based on a known formula.
So while many of the galactic spectral lines in today's APOD look similar, there are slight differences in each of them. This not only indicates how far each galaxy is from Earth, but also provides an idea of their predominant composition (e.g. hydrogen, nitrogen, oxygen, iron, etc). Analyzing the space distribution of distant objects will allow insight into when and how stars and galaxies formed, clustered, and evolved in the early universe.
APOD: 2020 September 20 - Breaking Distant Light
Posted from apod.nasa.gov
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Maj William W. 'Bill' Price good day my friend, I have said it over and will continue, " nobody does it better from above" . Thanks for the Astronomy Picture of the Day (APOD) is titled "Breaking Distant Light."
Have a great/ blessed day my friend.
SPC Margaret Higgins COL Mikel J. Burroughs CPL Dave Hoover Lt Col Charlie Brown Lt Col John (Jack) Christensen SCPO Morris Ramsey PVT Mark Zehner Sgt (Join to see) SSG Michael Noll SSG Robert Mark Odom CPL Douglas Chrysler PO1 Tony Holland SGT Steve McFarland SPC Mark Huddleston CW5 Jack Cardwell PO1 William "Chip" Nagel PO1 Lyndon Thomas PO3 Phyllis Maynard Wayne Soares
Have a great/ blessed day my friend.
SPC Margaret Higgins COL Mikel J. Burroughs CPL Dave Hoover Lt Col Charlie Brown Lt Col John (Jack) Christensen SCPO Morris Ramsey PVT Mark Zehner Sgt (Join to see) SSG Michael Noll SSG Robert Mark Odom CPL Douglas Chrysler PO1 Tony Holland SGT Steve McFarland SPC Mark Huddleston CW5 Jack Cardwell PO1 William "Chip" Nagel PO1 Lyndon Thomas PO3 Phyllis Maynard Wayne Soares
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Here's a larger diagram showing redshift. The spectral lines of the Sun are on the left. A hypothetical galaxy is shown on the right. The difference between the spectral lines is redshift.
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MSgt Paul Connors LTC Tom McNew LTC Stephen C. SSG Michael Noll SGT Steve McFarland LTC Stephen F. 1SG Steven Imerman Cpl (Join to see) Sgt Kelli Mays MSgt Robert "Rock" Aldi PO3 Lynn Spalding LTC (Join to see) SSG Gordon Holmes SMSgt Lawrence McCarterSGT Mark Anderson SPC Nancy Greene 1SG (Join to see) PO2 (Join to see) SGT Denny Espinosa SSG C.V. Shaw
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