超新星遗迹CTA 1

超新星遗迹CTA 1

Supernova Remnant CTA 1
Image Credit & Copyright: Thomas Lelu

Explanation: There is a quiet pulsar at the heart of CTA 1. The supernova remnant was discovered as a source of emission at radio wavelengths by astronomers in 1960 and since identified as the result of the death explosion of a massive star. But no radio pulses were detected from the expected pulsar, the rotating neutron star remnant of the massive star’s collapsed core. Seen about 10,000 years after the initial supernova explosion, the interstellar debris cloud is faint at optical wavelengths. CTA 1’s visible wavelength emission from still expanding shock fronts is revealed in this deep telescopic image, a frame that spans about 2 degrees across a starfield in the northern constellation of Cepheus. While no pulsar has since been found at radio wavelengths, in 2008 the Fermi Gamma-ray Space Telescope detected pulsed emission from CTA 1, identifying the supernova remnant’s rotating neutron star. The source has been recognized as the first in a growing class of pulsars that are quiet at radio wavelengths but pulse in high-energy gamma-rays.

Tomorrow’s picture: gone to Fiji

超新星遗迹CTA 1
影像提供与版权: Thomas Lelu

说明: CTA 1的中心有一颗安静的脉冲星/波霎。天文学家之所以能在1960年发现这个超新星遗迹，是因为它是无线电波辐射源，后来才认出它为大质量恒星爆炸死亡所留下的遗迹。然而，科学家于无线电波段，观测此大质量恒星的星核发生塌缩后应会孑遗下来的脉冲星（旋转中子星），但却无所得。在超新星爆炸约10,000年后，所见到的这团星际碎片云，于可见光波段很暗淡。不过，在这幅涵盖北天仙王座约2度宽星场的望远镜深空影像里，来自CTA 1不断扩张激波前沿的可见光辐射清楚可见。尽管在无线电波段一直未能发现脉冲星，但在2008年，费米伽马射线太空望远镜侦测到来自CTA 1的脉冲辐射，从而确认这个超新星遗迹有有颗旋转的中子星。此发现让它成为全新类别脉冲星的首个成员；这类脉冲星，在无线电波段很安静，但却会发出高能的伽马射线脉冲。

明日的图片: gone to Fiji