Eta Carinae Question

[robnissen]

So Eta Carinae is set to explode in a monstrous super nova at any time: it could be today, tomorrow, 10,000 years from now, or some other time. The risk to life on earth is minimal UNLESS we happen to be in the direct path of one of the two gamma ray jets shooting out from the star. My question is, since Eta Carinae is only visible from the southern hemisphere, is all the danger from the gamma ray jets limited to the Southern Hemisphere?

 

[MeteorWayne]

No, if I understand it correctly, it would destroy the entire ozone layer.<br />That's just what I recall off the top of my head. <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[deapfreeze]

And you want to be in the southern hemisphere if it blows MeteorWayne?<br /><br />Does not sound like fun LOL<br />cool to see though <div class="Discussion_UserSignature"> <p><font size="2" color="#0000ff"><em>William ( deapfreeze ) Hooper</em></font></p><p><font size="1">http://deapfreeze-amateur-astronomy.tk/</font></p><p> </p> </div>

 

[MeteorWayne]

Well, if the jets aren't pointed our way, sure <img src="/images/icons/cool.gif" /><br /><br />And if they are, might as well go out seeing the cause of our demise <img src="/images/icons/laugh.gif" /> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[deapfreeze]

well if there pointing our way send me a message and maybe I will come along just for fun. <div class="Discussion_UserSignature"> <p><font size="2" color="#0000ff"><em>William ( deapfreeze ) Hooper</em></font></p><p><font size="1">http://deapfreeze-amateur-astronomy.tk/</font></p><p> </p> </div>

 

[weeman]

Very true Borman. If it has already exploded, then it could be any day now that we actually see it. At a distance of about 7,500 lightyears, it is amazing to think that it could have already blown around the same time as modern man, yet we haven't even seen it yet. <div class="Discussion_UserSignature"> <p> </p><p><strong><font color="#ff0000">Techies: We do it in the dark. </font></strong></p><p><font color="#0000ff"><strong>"Put your hand on a stove for a minute and it seems like an hour. Sit with that special girl for an hour and it seems like a minute. That's relativity.</strong><strong>" -Albert Einstein </strong></font></p> </div>

 

[robnissen]

This could be ironic of astonishing proportions: Eta Carinae goes Super Nova right about the time that man is leaving his caves and making the first civilization, then 7500 years later that gamma ray beam reaches us, destroys civilization and sends man back to live in caves!

 

[dragon04]

I read somewhere that when E Car blows, you would be able to read by its light in the night. If you live in the Southern Hemisphere, that is.<br /><br />IIRC, our atmosphere would protect us from the GRB, but I wouldn't want to be on the ISS or in space, period when we experienced the effects of its explosion.<br /><br /> <div class="Discussion_UserSignature"> <em>"2012.. Year of the Dragon!! Get on the Dragon Wagon!".</em> </div>

 

[deapfreeze]

Wouldn't gamma rays wipe out our atmoshpere? Could we survive a direct hit from the gamma rays? <div class="Discussion_UserSignature"> <p><font size="2" color="#0000ff"><em>William ( deapfreeze ) Hooper</em></font></p><p><font size="1">http://deapfreeze-amateur-astronomy.tk/</font></p><p> </p> </div>

 

[bdewoody]

Like the man said, probably only if one of the star's poles is pointed straight at us. <div class="Discussion_UserSignature"> <em><font size="2">Bob DeWoody</font></em> </div>

 

[weeman]

Yes, I believe it would make night time in the Southern Hemisphere much brighter. I think it might also be visible during the day, similar to the way the Moon looks during a sunny day. <br /><br />If Earth survived the radiation, what affects would the luminosity of Eta have on our planet? Would its light be bright enough to have any impacts on plantlife or nocturnal creatures? <div class="Discussion_UserSignature"> <p> </p><p><strong><font color="#ff0000">Techies: We do it in the dark. </font></strong></p><p><font color="#0000ff"><strong>"Put your hand on a stove for a minute and it seems like an hour. Sit with that special girl for an hour and it seems like a minute. That's relativity.</strong><strong>" -Albert Einstein </strong></font></p> </div>

 

[derekmcd]

Gamma ray bursts are actually quite rare on the cosmological scale. Something on the order of one burst per galaxy every few hundred million years. It is not actually known if Eta Carinae will not produce a GBR, though the potential is there. If it should, we still have little to stress about as the polar axis is not pointing at us.<br /><br />With that said, though... If it did... and the GRB was intense enough, pointed directly at us, and lasted long enough, we would likely have a really bad day. Our atmosphere does protect us from gamma rays, but not from ones with the intensity produced by GRBs. <div class="Discussion_UserSignature"> <div> </div><br /><div><span style="color:#0000ff" class="Apple-style-span">"If something's hard to do, then it's not worth doing." - Homer Simpson</span></div> </div>

 

[derekmcd]

I would think the luminosity would have a negligible effect. If it did, it would be a minor, temporary nuiscance on very small, local scales. <div class="Discussion_UserSignature"> <div> </div><br /><div><span style="color:#0000ff" class="Apple-style-span">"If something's hard to do, then it's not worth doing." - Homer Simpson</span></div> </div>

 

[robnissen]

I agree with everything you said, except <font color="yellow">the polar axis is not pointing at us.</font><br /><br />We have absolutely no way of knowing which way the polar axis is pointing. It is as likely that its pointing at us, as that it is pointing 90 degrees away from us. I don't know what the sweep of the GRB would be, but if it is 1 degree, then we have a 1/180 chance of being hit by the GRB. Considering we are pretty certain that Eta Carinae is going to go supernova in the very near (geologic) future, this may be a higher risk to the earth, than an asteroid hitting us.

 

[MeteorWayne]

I think we do have a way. If you look at the image, seen from our perspective, it seems quite unlikely that the pole (at any of a few theoretical alignments) is pointing in our direction. <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[MeteorWayne]

LOL, ce <img src="/images/icons/smile.gif" /> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[MeteorWayne]

Nah, I think we just independantly arrived at the same answer to the question.<br /><br />Though your image is more colorful <img src="/images/icons/wink.gif" /> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[robnissen]

I stand corrected. I think the pictures you both posted makes it much more likely that we are not in the direction of the poles. Although I do think it is at least possible, that the gas cloud does not tell us where the gamma ray jets will be. But it is certainly less likely that we are in the line of fire.

 

[deapfreeze]

That makes me feel a little better that the poles don't appear to be facing us. <div class="Discussion_UserSignature"> <p><font size="2" color="#0000ff"><em>William ( deapfreeze ) Hooper</em></font></p><p><font size="1">http://deapfreeze-amateur-astronomy.tk/</font></p><p> </p> </div>

 

[MeteorWayne]

Rob, cool, you see what we are talking about. True, we don't know for sure where the jets might happen, but it appears that we are at least 60 degrees away from where I suspect the "current" poles are (upper left to lower right). (Or lower left to upper right <img src="/images/icons/smile.gif" /> )<br /><br />MW <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[MeteorWayne]

If it is rotating.....<br /><br />The point is, if the EM radiation from the star is aligned the way it is, and it exploded 7500 years ago, the alignment would still be the same as it is now when the gamma ray burst was ejected. <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[derekmcd]

I think borman's point is that we see it as it was 7500 years ago. We can't really know the direction the axis is pointing at today. I didn't even consider Eta Car's precession. I'm not even sure that is something we are capable of measuring and predicting unless it is something like a pulsar.<br /><br />Way to shake the confidence, borman <img src="/images/icons/wink.gif" /> <div class="Discussion_UserSignature"> <div> </div><br /><div><span style="color:#0000ff" class="Apple-style-span">"If something's hard to do, then it's not worth doing." - Homer Simpson</span></div> </div>

 

[MeteorWayne]

Yes, but my point is that if it exploded 7499 years ago, the jets would still be pointing the way we see them now when the EM waves were ejected, hence, not at us.<br />So what is pertinant is how it looks when it explodes, not whether it rotates after the explosion.<br /><br />If in a few thousand years it appears to be pointing at us, then we have reason to be worried if it exploded then. <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[CalliArcale]

<blockquote><font class="small">In reply to:</font><hr /><p>I think borman's point is that we see it as it was 7500 years ago.<p><hr /></p></p></blockquote><br /><br />Actually, we see the expanding cloud around Eta Carinae as it was 7500 years ago. The explosion that produced the cloud took a couple hundred years to get that big (if I'm understanding things correctly), since the brilliant explosion was actually observed on Earth a couple hundred years ago.<br /><br />It does seem likely that the cloud indicates the position of its rotational axes, but I just don't know astrophysics well enough to be confident about anything. <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>

 

[derekmcd]

I fully understand how C works when speaking in terms of time scale. The points you two make are indeed correct. I had made post prior, simply stating, we should have no worries about a GRB heading our way. In that post it is fair to think I was implying past, present or future and borman simply reminded me that the rotational axis can change. A point I overlooked. <div class="Discussion_UserSignature"> <div> </div><br /><div><span style="color:#0000ff" class="Apple-style-span">"If something's hard to do, then it's not worth doing." - Homer Simpson</span></div> </div>