APOD on Nostr: **Astronomy Picture of the Day** 22 July 2025 **A Double Detonation Supernova** ...
**Astronomy Picture of the Day**
22 July 2025
**A Double Detonation Supernova**
*Image creditor details unavailable via API. Visit linked page below for full info.*
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.
#APOD #SpaceIndustry #BlackHoles #AstronomyPhotography #GalaxyExploration
https://apod.nasa.gov/apod/ap250722.htmlPublished at
2025-07-22 04:08:04 GMTEvent JSON
{
"id": "093806eb9abfc04c4769d5def4b2ae6f1849819c3c72f4b7535041d209ad3ae2",
"pubkey": "e85ed75286cb77475776c1007df8c4ff1c9c68eff91c3627347b065c5bf4dc78",
"created_at": 1753157284,
"kind": 1,
"tags": [],
"content": "**Astronomy Picture of the Day**\n\n22 July 2025\n\n**A Double Detonation Supernova**\n\nhttps://apod.nasa.gov/apod/image/2507/DoubleSN_ESO_3000.jpg\n\n*Image creditor details unavailable via API. Visit linked page below for full info.*\n\nCan 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.\n\n#APOD #SpaceIndustry #BlackHoles #AstronomyPhotography #GalaxyExploration\n\nhttps://apod.nasa.gov/apod/ap250722.html\n",
"sig": "6e522d729037f99eada0d31bb5fdf64756d62e1113e1285767a8386158ef4fe020ae733b826e87b35d38e64bf6e2ea1b14b9df8c7230fb4772920d946fc9689b"
}
