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Astronomy Picture of the Day - A Double Detonation Supernova
NASA ^ | 22 Jul, 2025 | Image Credit: ESO, P. Das et al.; Background stars (NASA/Hubble): K. Noll et al.

Posted on 07/22/2025 12:46:31 PM PDT by MtnClimber

Explanation: Can some supernovas explode twice? Yes, when the first explosion acts like a detonator for the second. This is a leading hypothesis for the cause of supernova remnant (SNR) 0509-67.5. In this two-star system, gravity causes the larger and fluffier star to give up mass to a smaller and denser white dwarf companion. Eventually the white dwarf's near-surface temperature goes so high that it explodes, creating a shock wave that goes both out and in -- and so triggers a full Type Ia supernova near the center. Recent images of the SNR 0509-67.5 system, like the featured image from the Very Large Telescope in Chile, show two shells with radii and compositions consistent with the double detonation hypothesis. This system, SNR 0509-67.5 is also famous for two standing mysteries: why its bright supernova wasn't noted 400 years ago, and why no visible companion star remains.


TOPICS: Astronomy; Astronomy Picture of the Day; Science
KEYWORDS: apod; nasa; nova; supernova

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1 posted on 07/22/2025 12:46:31 PM PDT by MtnClimber
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To: MtnClimber

2 posted on 07/22/2025 12:46:53 PM PDT by MtnClimber (For photos of scenery, wildlife and climbing, click on my screen name for my FR home page.)
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To: MtnClimber

bttt


3 posted on 07/22/2025 12:47:23 PM PDT by BenLurkin (The above is not a statement of fact. It is opinion or satire. Or both.)
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To: 21stCenturion; 21twelve; 4everontheRight; A Navy Vet; A_perfect_lady; abb; AFB-XYZ; AFPhys; ...
Pinging the APOD list

🪐 🌟 🌌 🍔

4 posted on 07/22/2025 12:47:47 PM PDT by MtnClimber (For photos of scenery, wildlife and climbing, click on my screen name for my FR home page.)
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To: MtnClimber

I have a musket that bangs twice. :}


5 posted on 07/22/2025 1:01:25 PM PDT by sasquatch (Do NOT forget Ashli Babbit! c/o piytar)
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To: MtnClimber

Wow.


6 posted on 07/22/2025 1:02:23 PM PDT by No name given ( Anonymous is who you’ll know me as)
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To: MtnClimber

Rough neighborhood.


7 posted on 07/22/2025 1:30:56 PM PDT by BlackbirdSST
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To: MtnClimber

Rodney Mckay was responsible.


8 posted on 07/22/2025 1:51:42 PM PDT by minnesota_bound (Making money now. Still want much more.)
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To: MtnClimber

9 posted on 07/22/2025 4:48:09 PM PDT by Deaf and Discerning
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To: MtnClimber

Double-tap, cosmos style.


10 posted on 07/22/2025 5:44:45 PM PDT by AFB-XYZ (( We have two options: 1. Stand up, or 2. Bend over))
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