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The Astronomy Photos of the Year 2017 have been announced.
#12 is a 1000mm zoom of moonset over Mauna Kea:
https://www.theguardian.com/science/gall...ures#img-1
The Donner Party really wasn't that great of a party, was it?
"I'm at that stage in life where I stay out of discussions. Even if you say 1+1=5, you're right - have fun." - Keanu Reeves
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" Surface helium detonation spells end for white dwarf"
This is an interesting one which came from observations carried out by the Subaru Observatory on MK. In general, there are two types of supernovae (stars that end their lives by blowing themselves to pieces). Unlike a star with a mass similar to our sun, massive stars end their lives by running out of fuel. This means they can no longer hold up against their own force of gravity. They collapse which increases the pressure and temperature inside the star and you get runaway nuclear fusion and a huge explosion.
The other type is when the dense but small remnant of a star like our sun has a companion star. The dense white dwarf accretes material from its companion's surface layers until it has more mass than it can cope with and again, explodes. In this particular case, it seems that an outer layer of helium on the white dwarf exploded blowing the star to smithereens. Although it's not specified in the article, I suspect this means the helium was taken off a companion red giant star, one which our own sun will become one day. Such stars run out of hydrogen leaving behind mostly helium. I've no idea what happened to the red giant companion after the supernova though.
https://phys.org/news/2017-10-surface-he...dwarf.html
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Thought this might interest some people here:
" VIDEO: Volcanic Worlds – Hawaii’s Kilauea and Jupiter’s Moon, Io"
http://www.bigislandvideonews.com/2017/1...s-moon-io/
It's about 11 minutes of an enthusiastic scientist explaining volcanism in our solar system including Kilauea and how studies of our volcanoes help understand what might be happening elsewhere in the solar system.
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Big Mahalo Tom K-- enthusiastic, pleasantly-accented description of activity on Io with tangential mention of Hawaii volcanism most for comparison purposes. I enjoyed watching.
-dwajs
-dwajs
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No problem, David. I should also mention that the full presentation is also available via that link at the bottom of the page (about an hour long). It's very interesting and as ever, the question session at the end is always worth watching.
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I didn't want to mention this until it became public, but I was at the MK Users' Committee when the following "award" was given to Ronald Thiel; an asteroid was named after him - "(9923) Ronaldthiel". Ronald was surprised to be invited to the meeting and it was great to see him being given the images of the asteroid named after him. This came about from his dedication to bringing higher efficiency lights to the Big Island that improved safety yet helped darken the skies for the population and wildlife.
http://www.bigislandvideonews.com/2017/1...fic-chief/
The link quotes a press release from the county:
" Hawai'i County Traffic Division Chief Ronald Thiel knows lights. Much of his work focuses on keeping local streets safe with street lights, traffic lights and hazard lights.
He also knows where lights are not helpful – when light pollution interferes with the work of astronomers and the lives of native wildlife. For Thiel’s work preserving “dark skies” in Hawai'i County, an asteroid was recently named in his honor – 9923 ronaldthiel.
The asteroid naming ceremony took place on September 28, 2017, presented by Dr. Richard Wainscoat of the University of Hawai’i at a meeting of the Mauna Kea User’s Committee in Hilo. The asteroid was first discovered by astronomer Bobby Bus on March 7, 1981, with an orbit of 1,723 days around the sun. It has a diameter of 2.55 miles.
Over the years, Thiel has doggedly pushed for innovation, sometimes going against the flow of traffic. Industry naysayers said it could not be done with Light-Emitting-Diode (LED) lamps, so he waited for technology to catch up, and he searched for the right manufacturer.
In 2009, the American Recovery and Reinvestment Act made it possible to take small steps with the purchase of the first LED street lamps. Subsequent County investments and a partnership with the State of Hawai'i resulted in the installation of 11,000 LED lamps on County and State roadways across Hawai'i Island. Hawai'i County, which is nearly the size of the state of Connecticut, became the first county in the nation to convert all of its street lights to LED lamps.
The LED lamps support the Island’s $58.4 million astronomy industry’s needs for dark skies. Island observatories scan the heavens to improve our understanding of the far reaches of space, including asteroids like the 9923 ronaldthiel.
The lamps use filters to remove the LED’s blue spectrum, resulting in improved visibility, safer roads, and reduced eye fatigue by cutting glare. The filtered lamps have also proven to be far less of an attraction for Hawai'i’s endemic threatened and endangered birds and bats. The highly-efficient lamps have also reduced electrical and maintenance costs by over 50 percent, so the new fittings, lamps and installation expenses will pay for themselves in five years. An added benefit is that the LED lamps have a life of 20 years. The low-pressure sodium bulbs they replaced typically lasted just over four years."
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An interesting sidenote....Greggor Ilagan invited Ron Thiel to attend the HPP Road Traffic Safety Committee mtg w/him about 4 yrs ago. Ron later arranged to donate HPP 75 stop signs...a very generous gesture.
How cool is that to get an asteroid named after you?! Couldn't happen to a nicer guy.
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That doesn't surprise me. I hadn't met him before the meeting a couple of weeks ago, but he came across as a genuinely nice guy. Seeing the smile on his face when he was given the picture was wonderful to see!
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Nice story about fellow Big Island resident Ron Thiel having an asteroid named after him. Thanks TomK.
Some years ago a dwarf planet beyond Neptune was discovered by either the Keck or Gemini telescope on Mauna Kea (I've read different versions of the story). Named Haumea for the Hawaiian goddess of childbirth, it also has two moons orbiting around it, Hiiaka and Namaka.
It's now been determined that it also has a ring, the first dwarf beyond Neptune discovered to have one:
What the new Nature findings mean for Haumea's classification is the long run is unclear. Is it an entirely new type of world? How many small bodies beyond Neptune have rings? At the moment, we have only a small sample of worlds to draw from for conclusions, and even less of those have been visited by spacecraft.
http://www.planetary.org/blogs/jason-dav...-ring.html
“Facts fall from the poetic observer as ripe seeds.” -Henry Thoreau
"I'm at that stage in life where I stay out of discussions. Even if you say 1+1=5, you're right - have fun." - Keanu Reeves
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TomK - great story about Ron - nice to see a guy whose job is so seldom noticed get recognized when he really puts forth the effort to make a difference for the community.
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