From Physorg.com
Comet Lovejoy was only discovered a couple of weeks ago. It was supposed to melt as it came so close to the sun that the temperatures would hit several million degrees.
But astronomers watching live with NASA telescopes were shocked when a bright spot emerged on the sun’s other side. Lovejoy lived.
Here’s some video of the encounter:
So the IPCC climastrologists were right. The sun ain’t no big deal.
Time for NASA to consider a close encounter mission with the sun? Hitch a ride on a sun-grazing comet. Now there’s a worthy technical challenge for them.
Richard111 said: “Hmm… after that slingshot, where’s Lovejoy going now?”
Off to see Lady Felsham.
What a refreshing post, nice to see some science be discussed after the barrage of political posting that have swallowed up this site since CG2. Thank you! 🙂
That is one great lesson in physics!
Wonder who now thinks such a comet would burn up steaking into OUR atmosphere? It may due to the great density of the molucules here.
Two, the radiation. E/m waves. I should not have such a hard time now explaining why the ir radiation from the surface of our eath only contributes a net of 23 W/m-2 to the atmosphere and have someone believe it, it’s true. People (climate scientists) always seem to leave the impression of this huge influence of I/R radiation just because all energy leave the earth by radiation, slightly more that 40% in the far infrared and microwave. No, just 23 W/m-2 from the surface and that is according to Trenberth own data. They just have hidden that fact so well and deep and have instilled wrong impressions.
NASA doing some real science. What’s this a back to basics expedition?
Whatever it is some good pictures. Perhaps the corona has high temperature but little heat.
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Richard111 says:
December 16, 2011 at 11:51 pm
Hmm… after that slingshot, where’s Lovejoy going now?
<<
Slingshot? This sounds like something from Star Trek. Lovejoy will continue on its conic-section orbit: ellipse, parabola, or hyperbola–probably ellipse. If they knew Lovejoy’s orbital parameters before it passed behind the Sun, then those parameters would remain unchanged.
Jim
That must of been one hot ride, no matter what the actual temperature was. I would put it in the VBH (very blooming hot) range.
“Now, Dasher! now, Dancer! now, Prancer and Vixen!
On, Comet! on Cupid! on, Donder and Lovejoy?!?!
To the top of old Sol! Thru the heat of the orb!
Now dash away! dash away! dash away all!”
As dry leaves that before the wild hurricane fly,
When they meet with an obstacle, mount to the sky,
So up to the Sun’s back the boulders they flew,
With the sleigh full of toys, and St. Nicholas too.
A Merry Xmas to all Watts readers
(with thanks to Clement Clarke Moore/Henry Livingston)
Craig M
The discussion about heat transfer requiring density is interesting!
Makes perfect sense by analogy with “It’s not the heat, it’s the humidity.” Water vapor makes more contact with the skin than air molecules, so it transfers more heat. But I’d never thought about it in terms of simple gas density.
Wonder if the effect is noticeable in the usual barometric variation? Does 80 degrees at 30.1 inches feel hotter than 80 degrees at 28.4 inches?
Several million degrees? Sun surface is only about 6000 C and so is the main portion of its radiation. And sun corona is too diluted to heat up anything big considerably.
Jim Masterson says:
December 17, 2011 at 2:21 am
“Slingshot? This sounds like something from Star Trek. Lovejoy will continue on its conic-section orbit: ellipse, parabola, or hyperbola–probably ellipse. If they knew Lovejoy’s orbital parameters before it passed behind the Sun, then those parameters would remain unchanged.”
I agree, what slingshot? But I noticed you said probably elliptical. And you could very well be right. Like an Oort comet. But if it’s elliptical the eccentricy would be like 0.995, maybe closer to 0.999. When I get some time I am going to calculate that with such a good measurement of it’s altitude above the surface. My main point was ‘that bugger’ is not coming back any time soon, like a thousand+ years if elliptical… if ever if not.
When I was developing a solar system simulation program years ago I had a favorite high elliptic orbit to test various integrators an I believe it was about e=0.96 with a period of something like 120 years. That certain ellipticity was special for all solved parameters of that orbit landed exact on whole numbers and that way you could tell precisely after an even number of years, you should find the body exactly at the same starting point with the same velocity vector exactly parallel to a circular orbit at that radial distance if no errors were injected by the integrator itself. But if I remember that test body’s closest approach was much higher that Lovejoy’s skimming perihelion altitude meaning much longer period.
Hoser says:
December 16, 2011 at 9:51 pm
Oh, and I almost forgot: Several million degrees, eh? Was that Kelvin or Celsius? ;->
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Bachelors, Hoser.
Richard111 said: “Hmm… after that slingshot, where’s Lovejoy going now?”
That’s not a comet, everyone knows that’s Destiny, fueling up on our sun’s corona. Then performing a slingshot to their next Stargate Universe (SGU) adventure.. Their stellar navigation must be off-line since they didn’t realize they reached home..
For those who need a point of reference:
http://stargate.wikia.com/wiki/Destiny
just having a little fun 🙂
joshua Corning asked:
“Why would melting change the the orbit of a comet?”
Remember “orbital mechanics” and man-made satellites around earth. To stay in orbit, the mass of the satellite must maintain a velocity commensurate with it’s orbital distance from the gravity well. That is why space trash keeps falling to earth. For those orbiting objects, their mass is constant, but their velocity varies.
But if the mass of the object changes, then the orbital trajectory will also change. “Heavier” (more mass) objects require more energy to maintain their orbit than “lighter” objects.
Also, a comet may have a highly eccentric orbit, but it is still subject to the mathematics of orbital mechanics.
So, as Comet Lovejoy left a visible trail as it flew past our sun, it was probably shedding mass. Less mass in the orbital mechanics equation will mean that Lovejoy’s trajectory will be altered.
“The surface of the sun is at several thousand degrees not several million.”
That depends on whether or not CRU is handling the analysis.
How many times have you heard the phrase “we were amazed/shocked”. Just shows how litle we know about the unknown or what a bloated ego we have!
Hoser says:
December 16, 2011 at 9:51 pm
Oh, and I almost forgot: Several million degrees, eh? Was that Kelvin or Celsius? ;->
First one, then the other. 8^D
I just like the way the cols tail is buffeted by the hot flares. Makes Lovejoy emerge from the far side looking like a bottle rocket.
@ur momisugly Newt Love:
“But if the mass of the object changes, then the orbital trajectory will also change.”
Trouble is NL, you are speaking of the wrong mass. You would have to change the sun’s mass since in orbits, check something like vis viva equation, is controlled by a term (M+m), M being the sun’s mass and m being the comet’s mass. Since the sun’s mass so dwarfs the comet’s, a loss of mass in the comet is going to do basically nothing (well, unmeasureable).
This comet was discovered in early December. Glad it didn’t come through our neighborhood. Not much time to activate the planetary defense shield.
Should be…..cold tail…..
Oh heck if Al can say the center of the earth is millions of the degrees then why can the sun be millions of degrees too?
“Astronomers say it probably wasn’t deadly because the comet was larger than they thought.” Really!
In spite of comet Temple-whatever being shown NOT to be a snowball but mostly rock when smashed by the large copper slug several yrs ago, these guys (clowns?) were “amazed” that Lovejoy didn’t behave like a snowball either…. so it still had to be a snowball but larger than they thought. GMAFB!
Never A Straight Answer – is it dogma or stupidity or incompetence or other?
When you’re hot, you’re hot. When you’re not, you’re not. In this case it seems to be hot and not hot at the same time. However, the videos were pretty cool.