weltevredenkaroo
April 1st, 2019, 11:32 AM
The South Africa Deep-Sky Journal Nightfall has two new DSO publications available for free download.
Nightfall April 2019 V.3 #2 (https://issuu.com/douglasbullis/docs/_nightfall_issue__5_v3__2)
There are a few articles of interest to northern observers in this issue:
Martin Heigan’s Vela Supernova Remnant (p.7) describes what happens in the million years after a supernova blast wave detonates into the complex environment a galaxy’s disc. The article opens with a stunning Hubble HOO Palette image acquired by South Africa’s Martin Heigan.
You CAN hear a scream in space (p.48) dissects the effects of gas pressure density waves (sound) in the extremely low densities and high temperatures of interstellar space. Middle C in space is roughly 40 octaves below middle C on a piano. First, invent a hearing aid that can detect one wave pulse per month. Then be patient.
For fans of those beautifully painstaking early astronomy maps and charts, Hevelius’s 1687 Selenographia was the first meaningful map of the moon’s surface. See p. 85. The lunar story goes on (p.96) to a sample of ten pages from his atlas of the constellations Firmamantum Sobiescanum. Many consider these to be the most artistically beautiful star maps ever made.
On the Trail of the Chameleon Tail (https://issuu.com/douglasbullis/docs/special_report__6_on_the_trail_of_t)
What would you do if you saw a 40-degree long streak in the sky as large as those glorious comets recorded in history? You would tell everybody, right?
But what if no one can see it because it is too faint? In fact, what if it is visible only in far-infrared, microwave, micron, and 21 cm radio bands?
So your problem then is how to make the invisible visible — and then figure out what it is.
On the Trail of the Chameleon’s Tail (https://issuu.com/douglasbullis/docs/special_report__6_on_the_trail_of_t) tracks down a feature that is startlingly obvious in the spectral bands generated by dust, but is so tenuous that it lies below the 25 MPSAS faintness limit of the human eye. It has been photographed only a few times by amateur astrophotographers, but only by stacking so many images together that the rest of the field looks horribly over-processed.
After dissecting 35 pages of clues, the Chameleon’s Tail is hypothesised to be the last surviving traces of an ancient supernova remnant as old as 2 million years.
This isn’t quite a discovery paper because the object was already recorded in images. Rather, this is a rediscovery paper because it’s the first attempt to analyse and hypothesise what the thing is. The professional community seems to have overlooked this jet-like feature, so we amateurs are asking them to go have a look.
Since you are in the neighbourhood, enjoy our other publications produced in the last year. (https://issuu.com/douglasbullis)
Thanks for reading — Doug Bullis & the editorial crew at Nightfall in S.Africa
Nightfall April 2019 V.3 #2 (https://issuu.com/douglasbullis/docs/_nightfall_issue__5_v3__2)
There are a few articles of interest to northern observers in this issue:
Martin Heigan’s Vela Supernova Remnant (p.7) describes what happens in the million years after a supernova blast wave detonates into the complex environment a galaxy’s disc. The article opens with a stunning Hubble HOO Palette image acquired by South Africa’s Martin Heigan.
You CAN hear a scream in space (p.48) dissects the effects of gas pressure density waves (sound) in the extremely low densities and high temperatures of interstellar space. Middle C in space is roughly 40 octaves below middle C on a piano. First, invent a hearing aid that can detect one wave pulse per month. Then be patient.
For fans of those beautifully painstaking early astronomy maps and charts, Hevelius’s 1687 Selenographia was the first meaningful map of the moon’s surface. See p. 85. The lunar story goes on (p.96) to a sample of ten pages from his atlas of the constellations Firmamantum Sobiescanum. Many consider these to be the most artistically beautiful star maps ever made.
On the Trail of the Chameleon Tail (https://issuu.com/douglasbullis/docs/special_report__6_on_the_trail_of_t)
What would you do if you saw a 40-degree long streak in the sky as large as those glorious comets recorded in history? You would tell everybody, right?
But what if no one can see it because it is too faint? In fact, what if it is visible only in far-infrared, microwave, micron, and 21 cm radio bands?
So your problem then is how to make the invisible visible — and then figure out what it is.
On the Trail of the Chameleon’s Tail (https://issuu.com/douglasbullis/docs/special_report__6_on_the_trail_of_t) tracks down a feature that is startlingly obvious in the spectral bands generated by dust, but is so tenuous that it lies below the 25 MPSAS faintness limit of the human eye. It has been photographed only a few times by amateur astrophotographers, but only by stacking so many images together that the rest of the field looks horribly over-processed.
After dissecting 35 pages of clues, the Chameleon’s Tail is hypothesised to be the last surviving traces of an ancient supernova remnant as old as 2 million years.
This isn’t quite a discovery paper because the object was already recorded in images. Rather, this is a rediscovery paper because it’s the first attempt to analyse and hypothesise what the thing is. The professional community seems to have overlooked this jet-like feature, so we amateurs are asking them to go have a look.
Since you are in the neighbourhood, enjoy our other publications produced in the last year. (https://issuu.com/douglasbullis)
Thanks for reading — Doug Bullis & the editorial crew at Nightfall in S.Africa