Scientists propose three scenarios for the creation of Dinkinesh’s contact-binary moon Selam
Click for original graphic.
Click for original image.
Scientists have now used the data obtained during Lucy’s close fly-by of the asteroid Dinkinesh in November 2023 to propose three scenarios to explain the existence of its contact-binary moon Selam, as well as the trough and equatorial ridge on Dinkinesh.
The image to the right shows Selam to the right of Dinkenesh. The graphic above shows the three scenarios proposed for Selam’s creation. This is figure 4 from the paper published today. From the caption:
Asteroids with diameters less than approximately 10 km are subject to spin-up by the YORP effect [changes to rotation and motion due to solar radiation impacting the asteroid’s surface]. Rapid spin of the primary and the associated centrifugal force eventually trigger a structural failure that leads to sudden mass shedding. This event might also have created the trough seen on Dinkinesh through the mass movement of a portion of the body. The shed material forms a ring, with some material coalescing into a satellite(s) and closer material eventually falling back to the surface at the equator to form the ridge. The formation of the contact binary may be the result of a merger of two satellites formed either in a single mass-shedding event (a) or in two separate events (b). An alternative scenario (c) is that Selam formed as a single object that subsequently underwent fission owing to spin–orbit coupling.
Of course, none of this is confirmed, though these hypotheses fit the available facts.
Lucy is presently heading to a fly-by of Earth in December 2024. It will then zip past another main belt asteroid in April 2025 before arriving in August 2027 among the Trojan asteroids in Jupter’s orbit. Once there it will visit at least eight different asteroids.
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In 2020 when the world panicked over COVID I wrote that the panic was unnecessary, that the virus was apparently simply a variation of the flu, that masks were not simply pointless but if worn incorrectly were a health threat, that the lockdowns were a disaster and did nothing to stop the spread of COVID. Only in the past year have some of our so-called experts in the health field have begun to recognize these facts.
Your help allows me to do this kind of intelligent analysis. I take no advertising or sponsors, so my reporting isn't influenced by donations by established space or drug companies. Instead, I rely entirely on donations and subscriptions from my readers, which gives me the freedom to write what I think, unencumbered by outside influences.
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Click for original graphic.
Click for original image.
Scientists have now used the data obtained during Lucy’s close fly-by of the asteroid Dinkinesh in November 2023 to propose three scenarios to explain the existence of its contact-binary moon Selam, as well as the trough and equatorial ridge on Dinkinesh.
The image to the right shows Selam to the right of Dinkenesh. The graphic above shows the three scenarios proposed for Selam’s creation. This is figure 4 from the paper published today. From the caption:
Asteroids with diameters less than approximately 10 km are subject to spin-up by the YORP effect [changes to rotation and motion due to solar radiation impacting the asteroid’s surface]. Rapid spin of the primary and the associated centrifugal force eventually trigger a structural failure that leads to sudden mass shedding. This event might also have created the trough seen on Dinkinesh through the mass movement of a portion of the body. The shed material forms a ring, with some material coalescing into a satellite(s) and closer material eventually falling back to the surface at the equator to form the ridge. The formation of the contact binary may be the result of a merger of two satellites formed either in a single mass-shedding event (a) or in two separate events (b). An alternative scenario (c) is that Selam formed as a single object that subsequently underwent fission owing to spin–orbit coupling.
Of course, none of this is confirmed, though these hypotheses fit the available facts.
Lucy is presently heading to a fly-by of Earth in December 2024. It will then zip past another main belt asteroid in April 2025 before arriving in August 2027 among the Trojan asteroids in Jupter’s orbit. Once there it will visit at least eight different asteroids.
Readers!
Please consider supporting my work here at Behind the Black. Your support allows me the freedom and ability to analyze objectively the ongoing renaissance in space, as well as the cultural changes -- for good or ill -- that are happening across America. Fourteen years ago I wrote that SLS and Orion were a bad ideas, a waste of money, would be years behind schedule, and better replaced by commercial private enterprise. Only now does it appear that Washington might finally recognize this reality.
In 2020 when the world panicked over COVID I wrote that the panic was unnecessary, that the virus was apparently simply a variation of the flu, that masks were not simply pointless but if worn incorrectly were a health threat, that the lockdowns were a disaster and did nothing to stop the spread of COVID. Only in the past year have some of our so-called experts in the health field have begun to recognize these facts.
Your help allows me to do this kind of intelligent analysis. I take no advertising or sponsors, so my reporting isn't influenced by donations by established space or drug companies. Instead, I rely entirely on donations and subscriptions from my readers, which gives me the freedom to write what I think, unencumbered by outside influences.
You can support me either by giving a one-time contribution or a regular subscription. There are four ways of doing so:
1. Zelle: This is the only internet method that charges no fees. All you have to do is use the Zelle link at your internet bank and give my name and email address (zimmerman at nasw dot org). What you donate is what I get.
2. Patreon: Go to my website there and pick one of five monthly subscription amounts, or by making a one-time donation.
3. A Paypal Donation or subscription:
4. Donate by check, payable to Robert Zimmerman and mailed to
Behind The Black
c/o Robert Zimmerman
P.O.Box 1262
Cortaro, AZ 85652
You can also support me by buying one of my books, as noted in the boxes interspersed throughout the webpage or shown in the menu above.
Such a wonderful puzzle.
I hope Lucy has more for us.