X-Ray Satellite Discovers Overlooked Nova
Written by Nicholos Wethington
Novae are kind of a big deal in the Universe, so you'd think that when one occurred we would notice, especially if it were visible to the naked eye. A star that exploded in June of 2007 in the constellation of Puppis, though, slipped by the network of professional and amateur astronomers that are dedicated to watching the skies for novel stars. Luckily, the orbiting X-ray telescope XMM-Newton just happened to be observing the area, and discovered the nova that everyone else had missed.
The satellite XMM-Newton is creating a survey of X-ray sources in the Universe, and on October 9, 2007 while turning from one target to another, it passed over a bright source of X-rays that was unexpected. The science team checked over their catalog of previously known X-ray sources in the area, but the only object with that location was the faint star USNO-A2.0 0450-03360039.
Andy Read of the University of Leicester and Richard Saxton of ESA’s European Space Astronomy Centre (ESAC), Spain quickly alerted other astronomers of the finding via the internet. Astronomers at the Magellan-Clay telescope at Las Campanas Observatory in Chile used their 6.5 meter telescope to analyze the light coming from the star and found that it had brightened by more than a factor of 600.
Saxton contacted the All-Sky Automated Survey, an automated survey of millions of stars, and found that the star went nova on June 5th, 2007. The nova has been given the shorter name of V598 Puppis, and had anyone been looking closely – even with the naked eye – at the constellation of Puppis on June 5th of 2007, they would have noticed the star brighten.
The image here shows V598 Puppis in the visible spectrum on the left, and in the X-ray on the right.
Novae of this type occur when a white dwarf, which is a smaller and more compact star, consumes material from a companion star, puffing it up. The nuclear processes in the star begin a runaway reaction after a certain amount of material is consumed, and it explodes violently.
What is curious about the case of V598 Puppis is that X-rays are only released from a nova after visible light. The expanding cloud of dust and debris from the initial explosion blocks most of the X-rays from being released. In the case of most other novae and supernovae, the discovery is made by a visible light telescope, then followed up by telescopes in the other spectra.
Source: ESA Press Release
Filed under: Astronomy
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July 18th, 2008 at 7:55 am
Coordination, people!
http://www.universetoday.com/2008/07/18/the-exploding-star-everyone-missed/
July 18th, 2008 at 9:15 am
yes, we apologize for the double post, and we're trying to delete one but the delete key isn't working!
July 18th, 2008 at 9:38 am
So is it a nova or supernova? The first post (now deleted) specifies nova and this latest post mixes the words supernova and nova together in the same article. I hope the bad astronomer knows the difference.
July 18th, 2008 at 10:29 am
If it was given a GCVS name, V598 Pup, it was a nova. SN are given names like SN2007ad.
Sorry, but this is surprisingly sloppy work. This whole thing should come down and be re-written.
July 18th, 2008 at 11:29 am
I read the ESA article and it ONLY refers to the star as going NOVA, the word supernova is not in the article.
July 18th, 2008 at 1:00 pm
I agree with Mike S, please re-write the article – including the title.
July 18th, 2008 at 2:31 pm
that the star went nova on June 5th, 2007.
Isn't this statement stupid? If the star went nova on that date for us to see, it really means this event happened years and years ago. Nobody seems to be putting light years into perspective.
July 18th, 2008 at 2:59 pm
let's attack this mystery by examing the working assumptions:
"X-rays are only released from a supernova after visible light. The expanding cloud of dust and debris from the initial explosion blocks most of the X-rays from being released."
now if I understand this correctly this is suggesting the intial type 1a supernova explosion is going to uninformally eject material/dust in a near perfect 360 direction from the center of the disturbance.
Am I incorrect in this assumptiuon?
therefore, one possible explanation is that under certain conditions the explosion is more concentrated and NOT uniformally dispursed…thus causing an irregular build up of "ejecti" that is simply temporaily in perfect alignment with Earth BOTH X-rays and the visible spectrum of light. If we had been in another area of the galaxy its would have been observed normally from ground based telescopes.
seems to me that makes perfect sense that explsions are NOT always uniform 360 degrees in their dispersal pattern and that ejecti can be easily influenced or blownback in on itsellf.
now what could casue it is the big mystery and why?
1. Could an irregular gravitational tug from a nearby star cause simulateoulsy a perfectly aligned momentum/ressonance that concentarted the ejecti.
2. Could blowback from the compaion binary-star that was obstensibly consumed by this super nova may have had chemical elemental properties at its core that impeded ist dispersal pattern thru some sort of inonization?
what do we know EXACTLY about the other stars near it and the composition of the binary that may have contributed to the nova?
if my reasoning is wrong, I more than welcom assitance since I am an electrical engineer who is trying to explore the science of astronomy as a hobby.
July 18th, 2008 at 11:42 pm
let's be kind to our fine authors, shall we? I suspect no one's getting rich writing/posting these interesting articles that we enjoy on a very regular and updated basis.
July 19th, 2008 at 4:37 am
I agree with robb. If those who leave the arrogant comments could do any better then let them try.
None of us are paying for this after all.
July 19th, 2008 at 7:59 am
robb & Greg have better manners than some others posting comments. Pobody's Nerfect. Thanks for all the great stuff you publish.
July 19th, 2008 at 9:18 am
I am sorry if my comment sounded gruff. I appreciate the Universe Today site as much as anyone. I think they do a great job and a great service to the public by bringing good scientific information on a regular basis.
However, in this case, they've really got it all wrong.
V589 Pup is a galactic nova, not a supernova, and the reason no one saw it go off in June 2007, even though it was naked eye brightness, is because Puppis is essentially in conjunction with the Sun in June.
I've taken Greg up on his challenge "If those who leave the arrogant comments could do any better then let them try" and written a clarification of the facts on my blog.
July 19th, 2008 at 1:20 pm
The article talks about a Supernova, when hte object is in fact a Nova.
There are similarities between a nova and a type !a supernova, both including white dwarfs accreting matter from a nearby companion, but the explosive mechansim are quite different. The Nova blasts off a small, maybe irregular, shell of matter where the rest of the white dwarfs remains intact. A Supernova type 1a obliterates the white dwarf completely because the thermonuclear detonation happens at a state where the white dwarf is crossing the chandrasekhar mass-limit of little over 1.4 Msun.
Nova are often recurring, possibly always recurring, and some might end up as type 1a Supernova at the end of the line.
July 20th, 2008 at 6:18 pm
Its interesting that the white dwarf can be completely obliterated if it crosses the Chandrasekhar mass-limit (1.5m)…that sounds like a cosmological relief valve that prevents dangerous implosion on purpose.
Also a white dwarf if I understand correctly can be the diameter of Earth with a mass equivalent to 5 metric tons per teaspoon full (bear in mind that calculation is naturally going to be scrutinzed over the years to come)..
we still need to go back and re-evaluate these basic working assumptions of star death..moreover I would NOT be surpised if these obliterated white drwarfs (type 1a novas) are playing a much much bigger role even in protoplanetary formation…not just death from a binary relationship.
would a proto planet be better served if it were formed around a small remnant of a obliterated highly dense and ionized white dwarf and how would such a thing effect a terrestrial planets magnetosphere if it was forming around its core near the protostar?
to what degree is it obliterated and do these obliterated white dwarf remants pentrate the forming protostar? do we see evidence of their gravitational proximity in these birth events?
July 21st, 2008 at 1:33 pm
Thanks all for pointing out the glaring error of using supernova instead of nova. The event was indeed a nova. I've fixed the incorrect usages and the title. Thanks for keeping me honest!
July 22nd, 2008 at 1:32 am
Mike Simonsen, quite an astute observation on the location of the sun along with an interesting and amusing clarification on your blog. I hope you realize this not only makes you an arrogant commenter with poor manners but also an elitist. Keep up the good work!
July 22nd, 2008 at 4:30 pm
Stephen:
Type 1a Supernovas do have some effect on triggered starformations, but since they are decently rare, and since it takes quite awhile for such a scenario to reach the end, core collapse SN should have significantly larger impact.
1. The star must become a white dwarf, without going supernova by core collapse. This rules out stars that start with more than about 8 Msun.
2. It must still have a small companion that reaches the midlife crisis and start transferring matter over to the white dwarf. The companion may be speeded up in its aging though by masstransner from the 'to-be' white dwarf while it is still a red giant
3. The white dwarf must reach the chandrasehkar mass limit, and the transfer mechanism isnt the fastest.
Most likely, that white dwarf will go nova a number of times as it accretes fresh hydrogen from its companion, slowly gaining mass overall (but loosing some each time it goes nova).
Then, when the mass is around the Chandrasekhar limit, a small increase in mass leads to large contraction of the white dwarf, wich heats the interior up enough to start fusion of carbon/oxygen in the core. This is the important difference between type 1a and core-collapse, the core still contains fusable matter in a white dwarf. Core collapse SN have run out of 'fuel' completely.
And since a white dwarf is degenerate, the increase in temperature to start with does not lead to increased internal pressure, so the temperature becomes higher and higher, and the fusion becomes faster and faster, and when the carbon/oxygen runs out, the heavier byproducts ignite – eventually the temperature is so high that radiation pressure becomes dominant and the fusing core rapidly expands.
This long set of events make type 1a Supernovas less important in triggering new stars in starforming regions (likely starforming has subsidid at that time), and core collapse supernovas more likely (as they only have the requirement for 1 initial star with more than about 8Msun mass, wich is common in fresh starforming regions). Type 1a do however spew out a significantly larger portion of heave elements compared to core-collapse, especially iron and nickel, so they do have an impact on life.
Type 1a is very interesting as a standard candle, as they always have the about same mass (Chandrasekhar limit) and so have similar total energy output.
Anything that can explode is intersting though,, be it a Nova, a Supernova, or a fire-cracker.
July 23rd, 2008 at 4:11 pm
I'm new at astronomy, but when looking over all the news, I can't seem to find out how far away this even is.
August 13th, 2008 at 10:23 am
Okay people….glad I found this site.They (s.novas) do happen.I witnessed one. Period.Beautiful.Quick.Maybe 5 or 6 seconds.2005.March.About the size of a small full moon pushed back out a bit into space.Pulsated yellowish orange.Almost could hear the power and energy of it.But no….no real noise.Only in ones minds eye.Whew….okay so after pulsating for moments….it collasped so fast….faster than even speed.The word "fast" does not give respect to the movements scale.When it collasped there was no trace. only blackness.I am rare he who sees and witnesses.But by God………it happened.March 2005.I can give the date depending upon where you were in the world (time zone,location,etc)Surely someone in the world witnessed it besides me???????? cliffdotfranklin@yahoo.com