APOD: CME, Comet, and Planet Earth (2013 Mar 15)

[APOD Robot]

CME, Comet, and Planet Earth

Explanation: After appearing in a popular photo opportunity with a young crescent Moon near sunset, naked-eye Comet PanSTARRS continues to rise in northern hemisphere skies. But this remarkable interplanetary perspective from March 13, finds the comet posing with our fair planet itself - as seen from the STEREO Behind spacecraft. Following in Earth's orbit, the spacecraft is nearly opposite the Sun and looks back toward the comet and Earth, with the Sun just off the left side of the frame. At the left an enormous coronal mass ejection (CME) is erupting from a solar active region. Of course, CME, comet, and planet Earth are all at different distances from the spacecraft. (The comet is closest.) The processed digital image is the difference between two consecutive frames from the spacecraft's SECCHI Heliospheric Imager, causing the strong shadowing effect for objects that move between frames. Objects that are too bright create the sharp vertical lines. The processing reveals complicated feather-like structures in Comet PanSTARRS's extensive dust tail.

<< Previous APOD

This Day in APOD

Next APOD >>

[/b]

[starstruck]

Very cool APOD! The 11 second video clip (off the "remarkable... " link) is absolutely fantastic too! I've tried to see the comet myself, but we've been under miserable grey skies this week

Note to the editors: the "discuss" link on the APOD page points towards yesterday's discussion.

[saturno2]

This image is very good
The planet Earth from the space

[zbvhs]

The feathery structure has been seen before as I recall. What I find interesting is the two "jets" at extreme angles to the rest and the curly structure in the one second from the top. Any idea what might be causing these?

[JohnD]

Note to the editors: the "discuss" link on the APOD page points towards yesterday's discussion.

And as Margarita has pointed out elsewhere, the APOD is dated yesterday, above the image.
Some sort of indexing glitch?
John

[nstahl]

Clicking "Diuscuss" takes me to yesterday's discussion.

Nice APOD.

[JohnD]

Er, yes, nstahl.
See post 2, and mine just above yours?
The more the merrier!
(Owlice tells me that the glitch has been reported)
John

[nstahl]

John had you looked a little closer you'd have seen our comments came in at virtually the same time. While yours went up I was hitting "Submit". What's your problem?

[yasgur]

Very cool shot. What are the little double spots that look like quotation marks. Some kind of artifacting or are background stars being doubled?

[stephen63]

Very cool shot. What are the little double spots that look like quotation marks. Some kind of artifacting or are background stars being doubled?

As stated, the images are layered using difference blending mode. Ideally, if both frames are aligned properly, the stars would be completely black. The images are misaligned (just guessing), or the stars are of different brightness between exposures.

[stephen63]

I looked a little closer, and they are not misaligned.

[owlice]

Some sort of indexing glitch?
John

These links are done by hand. Actually, all the links are done by hand by the editors. They are their own content management system!

[LocalColor]

Wonderful image today, the links are fascinating (and working.)

[neufer]

The feathery structure has been seen before as I recall. What I find interesting is the two "jets" at extreme angles to the rest and the curly structure in the one second from the top. Any idea what might be causing these?

Click to play embedded YouTube video.

Comet PANSTARRS from the other side of the Sun!
Posted By Karl Battams, 2013/03/14 05:21 CDT

<<What you might... notice in the PANSTARRS movie is that there’s actually more than one tail on this comet. In fact, there are at least three! The first one is the big dust tail I just spoke about, and by far the dominant feature of the comet. But if you watch the movie again we can see a short spikey tail pointing towards the lower-left of the images. This is very likely to be another dust tail, but one composed of very large and heavy pieces of cometary material that are not so easily influenced by the solar wind or radiation pressure. Instead, they’re big enough that they simply continue to follow the comet in its orbit, rather than being pushed outwards by other forces. Many of the higher-quality images taken from Earth also show this tail.

In addition to those two dust tails, on the right of the comet nucleus we see a thin third tail pointing radially away from the Sun. This is an “ion” or “gas” tail and is the result of the solar wind ionizing the neutral gas in the comet’s coma and releasing a stream of ions pointing directly away from the Sun. Interestingly, these ions can be highly affected by magnetic fields, and it just so happens that the solar outflow in general contains a very complicated and highly variable magnetic field. The result of this is that we frequently see twists and turns in the ion tail of comets, particularly in our STEREO images. Actually, though, PANSTARRS' ion tail is holding very steady. This might be a hint that it is composed of slightly more “exotic” ions than we typically see; perhaps Fe+, but we are going to need to turn to our computer models to figure that out!>>

[Boomer12k]

Interesting perspective.

Another one was a picture of a small blob with another smaller blob very close to it, and stars in the background. It was from the Messenger spacecraft about to orbit Mercury at the time, I think, and the picture was of Earth and the Moon...

:---[===] *

[Anthony Barreiro]

I'm grateful that we have eyes in the sky, watching the other side of the Sun, looking back at our home planet, and catching serendipitous views of passing comets. It makes me think of Pierre Teilhard de Chardin's concept of the noosphere, although so far as I know Teilhard de Chardin, who died in 1955, never speculated about space probes as vehicles for expanding human consciousness.

Neufer, thanks for the link to the video of PanSTARRS as seen from STEREO-B and the helpful explanatory text about the different tails. What a messy comet! I wonder if we'll have new annual meteor showers when Earth passes through these dust trails in future years.

[Jacob]

Anyone have a link to the individual frames without the difference merging?

[JohnD]

Great minds think alike, nstahl!

But I was first, nah-nah-ne-nah-nah!
Childish John

[Canadian Grandma]

A big "thank you" to those people all around the world who have shared with us their photos of PanSTARRS, and also to our editors. A boon to those of us without equipment and/or keen enough eyesight to see it in "the flesh".

[bystander]

Interesting perspective.

Another one was a picture of a small blob with another smaller blob very close to it, and stars in the background. It was from the Messenger spacecraft about to orbit Mercury at the time, I think, and the picture was of Earth and the Moon...

:---[===] *

http://apod.nasa.gov/apod/ap100901.html

[mjimih]

http://www.nasa.gov/multimedia/videogal ... =161111841

here's a slightly different version of the video above, in color, with music