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zonination / h-r-diagram

Hertzsprung-Russell Diagram with 119,614 datapoints
MIT License
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'Supergiants' are indeed spurious #1

Open marksubbarao opened 7 years ago

marksubbarao commented 7 years ago

The 'supergiant' region of the diagram comes from bad absmag values in the HGY catalog. Stars with uncertain parallax are given a distance of 10 million parsecs (and for some reason that is used in the absmag calculation. These stars need to be filtered out of the diagram.

From the HGY cat description: Distance: The star's distance in parsecs, the most common unit in astrometry. To convert parsecs to light years, multiply by 3.262. A value of 10000000 indicates missing or dubious (e.g., negative) parallax data in Hipparcos.

zonination commented 7 years ago

Well this certainly explains the number of supergiants that are disproportionate.

Let me regenerate some time this week and I'll get back to you...