APOD: Sun Dance (2018 Oct 10)

Comments and questions about the APOD on the main view screen.
User avatar
APOD Robot
Otto Posterman
Posts: 3326
Joined: Fri Dec 04, 2009 3:27 am

APOD: Sun Dance (2018 Oct 10)

Post by APOD Robot » Wed Oct 10, 2018 4:05 am

Image Sun Dance

Explanation: Sometimes, the surface of our Sun seems to dance. In the middle of 2012, for example, NASA's Sun-orbiting Solar Dynamic Observatory spacecraft imaged an impressive prominence that seemed to perform a running dive roll like an acrobatic dancer. The dramatic explosion was captured in ultraviolet light in the featured time-lapse video covering about three hours. A looping magnetic field directed the flow of hot plasma on the Sun. The scale of the dancing prominence is huge -- the entire Earth would easily fit under the flowing arch of hot gas. A quiescent prominence typically lasts about a month, and may erupt in a Coronal Mass Ejection (CME) expelling hot gas into the Solar System. The energy mechanism that creates a solar prominence is still a topic of research. Unlike 2012, this year the Sun's surface is significantly more serene, featuring fewer spinning prominences, as it is near the minimum in its 11-year magnetic cycle.

<< Previous APOD This Day in APOD Next APOD >>

Donald Pelletier
Ensign
Posts: 20
Joined: Mon Apr 21, 2008 11:53 pm
Location: Valleyfield

Re: APOD: Sun Dance (2018 Oct 10)

Post by Donald Pelletier » Wed Oct 10, 2018 12:37 pm

SoHO is in orbit around the Sun, but not SDO who is in geosynchrone orbit ...(https://en.wikipedia.org/wiki/Solar_Dyn ... tory#Orbit)

Sa Ji Tario

Re: APOD: Sun Dance (2018 Oct 10)

Post by Sa Ji Tario » Wed Oct 10, 2018 1:06 pm

The SOHO orbits at Lagrange point L1 and the SDO is geosincron no orbit to the Sun

Sa Ji Tario

Re: APOD: Sun Dance (2018 Oct 10)

Post by Sa Ji Tario » Wed Oct 10, 2018 1:09 pm

They actually orbit the Sun NEXT to Earth

User avatar
Chris Peterson
Abominable Snowman
Posts: 13965
Joined: Wed Jan 31, 2007 11:13 pm
Location: Guffey, Colorado, USA

Re: APOD: Sun Dance (2018 Oct 10)

Post by Chris Peterson » Wed Oct 10, 2018 1:32 pm

Donald Pelletier wrote:
Wed Oct 10, 2018 12:37 pm
SoHO is in orbit around the Sun, but not SDO who is in geosynchrone orbit ...(https://en.wikipedia.org/wiki/Solar_Dyn ... tory#Orbit)
While I agree that the wording could be confusing, anything in geosynchronous orbit around the Earth is also orbiting the Sun. Earth just scallops the orbit a tiny bit. If Earth magically disappeared, SDO would happily continue around the Sun in almost exactly the orbit it currently occupies.
Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

User avatar
Fred the Cat
Theoretic Apothekitty
Posts: 463
Joined: Mon Feb 22, 2016 4:09 pm
AKA: Ron
Location: Eagle, Idaho

Re: APOD: Sun Dance (2018 Oct 10)

Post by Fred the Cat » Wed Oct 10, 2018 1:53 pm

These hydromagnetic expulsions are mere flashes in the pan considering the events that do overcome confinement of the sun’s plasma. It shall be interesting to discover more with Parker’s probe. :yes:

Maybe we'll all dance up a storm! :wink:
Freddy's Felicity "Only ascertain as a cat box survivor"

User avatar
neufer
Vacationer at Tralfamadore
Posts: 15337
Joined: Mon Jan 21, 2008 1:57 pm
Location: Alexandria, Virginia

Re: APOD: Sun Dance (2018 Oct 10)

Post by neufer » Wed Oct 10, 2018 3:19 pm

Chris Peterson wrote:
Wed Oct 10, 2018 1:32 pm
Donald Pelletier wrote:
Wed Oct 10, 2018 12:37 pm

SoHO is in orbit around the Sun, but not SDO who is in geosynchrone orbit ...(https://en.wikipedia.org/wiki/Solar_Dyn ... tory#Orbit)
While I agree that the wording could be confusing, anything in geosynchronous orbit around the Earth is also orbiting the Sun. Earth just scallops the orbit a tiny bit. If Earth magically disappeared, SDO would happily continue around the Sun in almost exactly the orbit it currently occupies.
So, by your definition: Nothing orbits the Earth:

All "Earth" satellites have v<12 km/s
  • 12 < 30 km/s such that they never make a loop in the opposite direction of the Earth.
    12 < 30 km/s [sqrt(2)-1] such that they could never escape the Sun if Earth disappeared.
Art Neuendorffer

User avatar
Chris Peterson
Abominable Snowman
Posts: 13965
Joined: Wed Jan 31, 2007 11:13 pm
Location: Guffey, Colorado, USA

Re: APOD: Sun Dance (2018 Oct 10)

Post by Chris Peterson » Wed Oct 10, 2018 3:44 pm

neufer wrote:
Wed Oct 10, 2018 3:19 pm
Chris Peterson wrote:
Wed Oct 10, 2018 1:32 pm
Donald Pelletier wrote:
Wed Oct 10, 2018 12:37 pm

SoHO is in orbit around the Sun, but not SDO who is in geosynchrone orbit ...(https://en.wikipedia.org/wiki/Solar_Dyn ... tory#Orbit)
While I agree that the wording could be confusing, anything in geosynchronous orbit around the Earth is also orbiting the Sun. Earth just scallops the orbit a tiny bit. If Earth magically disappeared, SDO would happily continue around the Sun in almost exactly the orbit it currently occupies.
So, by your definition: Nothing orbits the Earth:

All "Earth" satellites have v<12 km/s
  • 12 < 30 km/s such that they never make a loop in the opposite direction of the Earth.
    12 < 30 km/s [sqrt(2)-1] such that they could never escape the Sun if Earth disappeared.
No. Just that everything in orbit around the Earth is also in orbit around the Sun.
Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

Tszabeau

Re: APOD: Sun Dance (2018 Oct 10)

Post by Tszabeau » Wed Oct 10, 2018 4:53 pm

What role, if any, does the solar system have in the 11 year solar-cycle or is it a wholly internal affectation of the sun’s magnetic field?

User avatar
Chris Peterson
Abominable Snowman
Posts: 13965
Joined: Wed Jan 31, 2007 11:13 pm
Location: Guffey, Colorado, USA

Re: APOD: Sun Dance (2018 Oct 10)

Post by Chris Peterson » Wed Oct 10, 2018 5:00 pm

Tszabeau wrote:
Wed Oct 10, 2018 4:53 pm
What role, if any, does the solar system have in the 11 year solar-cycle or is it a wholly internal affectation of the sun’s magnetic field?
The gravitational effects of Jupiter (and to a much lesser extent the other planets) on the Sun are tiny. The cycle (which is actually 22 years, not 11) appears to be entirely the product of internal energy transfer within magnetic field components.
Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

De58te
Science Officer
Posts: 181
Joined: Mon Sep 30, 2013 6:35 pm

Re: APOD: Sun Dance (2018 Oct 10)

Post by De58te » Wed Oct 10, 2018 8:22 pm

Well, I can see a dark brown mountain like object in the center at the start of the video. (Course it is no earth mountain, I just call it that not knowing its name.) The magnetic prominence shoots along the surface and when it collides with this mountain it shoots up and over it creating the loop. So I am wondering what this object is called?

Alan Watson

Re: APOD: Sun Dance (2018 Oct 10)

Post by Alan Watson » Wed Oct 10, 2018 11:08 pm

The large dark material is a prominence see from one end. In a longer sequence it is quite dynamic.
I would like to see a long(24hrs)movie with high cadence of the whole event, as the prominence is torn down.
I have one big question, how many states of plasma are there? OK two, Are they all made of the same material? Oh dam a third, why is some material affected across large distances and others not?

Regards, Alan

Boomer12k
:---[===] *
Posts: 2331
Joined: Sun Apr 22, 2007 12:07 am

Re: APOD: Sun Dance (2018 Oct 10)

Post by Boomer12k » Thu Oct 11, 2018 12:38 am

My wood stove sometimes does the same thing. I have a flat piece of wood in there, and flames will lick around the top before it starts to burn, and will swirl around in a vortex...its awesome...

and of course...since my wood stove in on Earth...it orbits the Sun...

:---[===] *

User avatar
neufer
Vacationer at Tralfamadore
Posts: 15337
Joined: Mon Jan 21, 2008 1:57 pm
Location: Alexandria, Virginia

Re: APOD: Sun Dance (2018 Oct 10)

Post by neufer » Thu Oct 11, 2018 2:09 am

Click to play embedded YouTube video.
Boomer12k wrote:
Thu Oct 11, 2018 12:38 am

My wood stove sometimes does the same thing. I have a flat piece of wood in there, and flames will lick around the top before it starts to burn, and will swirl around in a vortex...its awesome...

and of course...since my wood stove in on Earth...it orbits the Sun...
The gravitational effects of Jupiter (and to a much lesser extent the other planets) on your wood stove are tiny.
Art Neuendorffer

Sothey Sae

Re: APOD: Sun Dance (2018 Oct 10)

Post by Sothey Sae » Fri Oct 12, 2018 8:56 pm

neufer wrote:
Thu Oct 11, 2018 2:09 am
Click to play embedded YouTube video.
Boomer12k wrote:
Thu Oct 11, 2018 12:38 am

My wood stove sometimes does the same thing. I have a flat piece of wood in there, and flames will lick around the top before it starts to burn, and will swirl around in a vortex...its awesome...

and of course...since my wood stove in on Earth...it orbits the Sun...
The gravitational effects of Jupiter (and to a much lesser extent the other planets) on your wood stove are tiny.
True, but if Earth magically disappeared, your wood stove would happily continue around the Sun in almost exactly the orbit it currently occupies.