APOD: SNR 0104: An Unusual Suspect (2009 Jun 12)

[neufer]

An Unusually LARGE Suspect

<<Explanation: SNR 0104 is a supernova remnant with an unusual shape. Found 190,000 light-years away in our neighboring galaxy the Small Magellanic Cloud, SNR 0104 is suspected of being the expanding debris cloud from a Type 1a supernova - the catastrophic thermonuclear explosion of a white dwarf star. For example, like Type 1a supernova remnants within our galaxy, investigations show that it contains large amounts of iron. But unlike other Type 1a remnants, including the well-studied Tycho, Kepler, and SN 1006, SNR 0104 is definitely not spherical. In fact, the remnant's shape suggests this supernova explosion was very asymmetric and produced strong jets. This intriguing composite image combines Chandra Observatory x-ray data of the remnant, shown in purple hues, with Spitzer Space Telescope infrared data covering the wider region, mapped to red and green colors. It indicates that the supernova explosion took place in the complicated and dense environment of a star-forming region. So, an alternative explanation is that the expanding debris cloud is sweeping up clumpy interstellar material, accounting for the odd shape of SNR 0104. The broad, multiwavelength view spans about 1,800 light-years at the estimated distance of SNR 0104.>>

1,800 light-years is about 100 times larger than Tycho, Kepler & SN 1006

[bystander]

<<Explanation: ... The broad, multiwavelength view spans about 1,800 light-years at the estimated distance of SNR 0104.>>

1,800 light-years is about 100 times larger than Tycho, Kepler & SN 1006

I think they are referring to the entire view, but even so, that would mean the snr is still > 100 ly across. Could this be an error? after all, it is in the SMC, only some 200,000 ly away.

From the Chandra press release: The full field image is 32.4 arcmin across (scale) and about 190,000 light years away (in the SMC) (distance).

[neufer]

<<Explanation: ... The broad, multiwavelength view spans about 1,800 light-years at the estimated distance of SNR 0104.>>

1,800 light-years is about 100 times larger than Tycho, Kepler & SN 1006

I think they are referring to the entire view, but even so, that would mean the snr is still > 100 ly across. Could this be an error? after all, it is in the SMC, only some 200,000 ly away.

Oops! You're right about the size. (I really shouldn't post before 6 AM !)

The ~ 6,500 year old Veil Nebula is ~100 ly across

It's not surprising IMO that SNRs this large are distorted by interactions:

<<The Local Bubble is a cavity in the interstellar medium (ISM) of the Orion Arm of the Milky Way. It is at least 300 light years across and has a neutral hydrogen density approximately one tenth of the 0.5 atoms per cubic centimetre average for the ISM in the Milky Way. The hot diffuse gas in the Local Bubble emits X-rays. The very sparse, hot gas of the Local Bubble is the result of supernovae that exploded within the past two to four million years. The most likely candidate for the remains of this supernova is "Geminga" ("Gemini gamma-ray source"), a pulsar in the constellation Gemini.>>

[kovil]

<<. . .The hot diffuse gas in the Local Bubble emits X-rays. The very sparse, hot gas of the Local Bubble is the result of supernovae that exploded within the past two to four million years. The most likely candidate for the remains of this supernova is "Geminga" ("Gemini gamma-ray source"), a pulsar in the constellation Gemini.>>

Gee, when I went to the dentist last week and he x-rayed my teeth, he gave me the choice of him using two neutron stars placed into close proximity or an artificial singularity with an accretion disk, as the methods for him generating the x-rays. I told him my dental insurance plan wouldn't pay for either of those, and went looking for a different dentist.

[bystander]

HEAPOW: What Broke the Ball? (2009 June 22)

Chandra: SNR 0104-72.3: Supernova Remnant is an Unusual Suspect