Starship Asterisk*

[img]http://apod.nasa.gov/apod/calendar/S_151102.jpg[/img] Comet ISON Being Destroyed by the Sun

Explanation: Most comets don't survive a close encounter with the Sun. Two years ago this month, though, Comet ISON was thought by some to be big enough to withstand its perilous sungrazing dive. The featured video shows the drama as it was recorded by NASA's Solar and Heliospheric Observatory (SOHO) satellite. As many Earthlings watched in fascination, a bright area did emerge from closest approach, but it soon faded and dispersed. It is now assumed that no large fragments of Comet C/2012 S1 (ISON) survived. Besides the comet, the active Sun is seen to eject puffs of plasma known as coronal mass ejections. Launched in 1995, sun-orbiting SOHO has become a historic device in the discovery and tracking of comets known as sungrazers. Two months ago, a comet designated SOHO 3000 was named in honor of the record 3000th comet that was discovered on SOHO images, a total that amounts to about half of all known comets.

<< Previous APOD

This Day in APOD

Next APOD >>

[/b]

What't the black gap we see from center to 2'o clock position on the masked sundial ?

ShaileshS wrote:What't the black gap we see from center to 2'o clock position on the masked sundial ?

That is the occulter pylon that supports the solar occulter disk

http://lasco-www.nrl.navy.mil/index.php?p=content/intro

Comet Bush!

About half of all known comets? According to the MPC, the total number of comets is 3857, so that should in fact be 78% of all comets.

Maybe it just ran out of ice, and dust, and is just a "dead" body now? or did it totally disintegrate??? I ask as the videos show something coming out the other side, and fading...but not separating...

:---[===] *

Is that Saturn crossing from left to right across the bottom?

What filters were used to observe the Sun?

Boomer12k wrote:Maybe it just ran out of ice, and dust, and is just a "dead" body now? or did it totally disintegrate??? I ask as the videos show something coming out the other side, and fading...but not separating...

As noted, it appears that no large fragments survived. The volatiles were lost and what presumably emerged was a pile of rocky rubble, some of which probably dissipated and some of which remains loosely bound, although that's likely to come apart over time and feed the sporadic meteor sources in our solar system.

Boomer12k wrote:Maybe it just ran out of ice, and dust, and is just a "dead" body now? or did it totally disintegrate??? I ask as the videos show something coming out the other side, and fading...but not separating...

:---[===] *

There once was a Comet named ISON
Twas promised "The best you'll lay Eyes on"
although near the end
it did brighten again
it fizzled out into a Bye-Gone

Hibernia wrote:
About half of all known comets?

According to the MPC, the total number of comets is 3857, so that should in fact be 78% of all comets.

• 3857 appears to be the number of "Comets Discovered" through the MPC:

http://www.minorplanetcenter.org/ wrote:
Comets Discovered: 3857

<<The Minor Planet Center, or MPC, is the single worldwide location for receipt and distribution of positional measurements of minor planets, comets and outer irregular natural satellites of the major planets. The MPC is responsible for the identification, designation and orbit computation for all of these objects. This involves maintaining the master files of observations and orbits, keeping track of the discoverer of each object, and announcing discoveries to the rest of the world via electronic circulars and an extensive website. The MPC operates at the Smithsonian Astrophysical Observatory, under the auspices of Division F of the International Astronomical Union (IAU).>>

Edd wrote:Is that Saturn crossing from left to right across the bottom?

I wondered the same thing, since there don't appear to be diffraction spikes on anything else visible.

SOHO is 20 years old? Where does the time go?

SOHO's been sitting out in the solar wind for two decades. In the video, you can see charged particle 'sleet' on the sensor. This can't be good for the electronics. Are there any plans for a successor?

Is it just me, or does it look like the flare/mass ejection/whatever is the last straw that blows away the coma?

stolenmoment wrote:Is it just me, or does it look like the flare/mass ejection/whatever is the last straw that blows away the coma?

Probably not. I don't know for sure, but most likely the ejection didn't even hit the comet- we're seeing it in front of or behind the remnants.

Edd wrote:Is that Saturn crossing from left to right across the bottom?

No, it's the star Antares (alpha Scorpius).

neufer wrote:3857 appears to be the number of "Comets Discovered" through the MPC

Yes maybe they just haven't got round to cataloging all the Soho discoveries -

Here's a list of Last Observation dates:

http://www.minorplanetcenter.net/iau/li ... etObs.html

and an historical list, including hundreds of Sohos:

https://www.ast.cam.ac.uk/~jds/cbat140.txt

In the information brought up through the "video" link in the explanation it states of the video "Published on Oct 30, 2015. Credit: NASA, SOHO Observatory. Occurred in 2014 November", but at least the "Occurred in 2014 November" is wrong as the event was in November 2013 (as noted on the video and indicated in the explanation). I thought I would mention the error so that someone may be able to correct it, as it is confusing.

If you want it to be corrected, you'll have to email them directly. I doubt the caretaker of their website looks at this forum.

geckzilla wrote:If you want it to be corrected, you'll have to email them directly. I doubt the caretaker of their website looks at this forum.

Wow that was a quick response geckzilla .

I'm surprised that at least the SOHO media people have apparently not noticed the error. I will however take it no further.