Green light for a close encounter: 'Jupiter-sized streak past Earth tonight

Originally posted by expatwhite
Surely that cant possibly be right

"Jupiter sized" ??? i always thought Jupiter wasnt far off being large enough to have become a sun (thanks Arthur C Clarke 2010). How can an object that large naff around the solar system without seriously wonkying up the orbits of stuff?

It cant be that big really can it?

Jupiter isn't even close to having enough mass to become a sun. That stuff you talk about is a hoax, I looked into it.

Jupiter would have to become like 80 times it's current mass just to become the smallest mass of a star theoretically. Even bigger than that to become as big as the smallest known star.

Our sun makes up 99% of our solar systems mass.

All the talk of "igniting" planets and such is a hoax. They aren't even close to having enough mass to sustain what is needed.

Jupiter's actual mass is 317.83 times the Earth's mass.

en.wikipedia.org...

With a mass only 93 times that of Jupiter, AB Doradus C, a companion to AB Doradus A, is the smallest known star undergoing nuclear fusion in its core.[75] For stars with similar metallicity to the Sun, the theoretical minimum mass the star can have, and still undergo fusion at the core, is estimated to be about 75 times the mass of Jupiter.[76][77] When the metallicity is very low, however, a recent study of the faintest stars found that the minimum star size seems to be about 8.3% of the solar mass, or about 87 times the mass of Jupiter.[77][78] Smaller bodies are called brown dwarfs, which occupy a poorly defined grey area between stars and gas giants.

The combination of the radius and the mass of a star determines the surface gravity. Giant stars have a much lower surface gravity than main sequence stars, while the opposite is the case for degenerate, compact stars such as white dwarfs. The surface gravity can influence the appearance of a star's spectrum, with higher gravity causing a broadening of the absorption lines.[17]

The closest it could become would be a brown dwarf. Which I think it does have enough mass to be. This is a bit of a grey area, and today they say 13 times the mass of jupiter is needed to be a brown dwarf.

en.wikipedia.org...

Distinguishing low mass brown dwarfs from high mass planets

A remarkable property of brown dwarfs is that they are all roughly the same radius as Jupiter. At the high end of their mass range (60-90 Jupiter masses), the volume of a brown dwarf is governed primarily by electron degeneracy pressure[2], as it is in white dwarfs; at the low end of the range (1-10 Jupiter masses), their volume is governed primarily by Coulomb pressure, as it is in planets. The net result is that the radii of brown dwarfs vary by only 10-15% over the range of possible masses. This can make distinguishing them from planets difficult.

In addition, many brown dwarfs undergo no fusion; those at the low end of the mass range (under 13 Jupiter masses) are never hot enough to fuse even deuterium, and even those at the high end of the mass range (over 60 Jupiter masses) cool quickly enough that they no longer undergo fusion after some time on the order of 10 million years. However, there are other ways to distinguish dwarfs from planets:

Density is a clear giveaway. Brown dwarfs are all about the same radius; so anything that size with over 10 Jupiter masses is unlikely to be a planet.

X-ray and infrared spectra are telltale signs. Some brown dwarfs emit X-rays; and all "warm" dwarfs continue to glow tellingly in the red and infrared spectra until they cool to planet like temperatures (under 1000 K).

Some astronomers believe that there is in fact no actual black-and-white line separating light brown dwarfs from heavy planets, and that rather there is a continuum. For example, Jupiter and Saturn are both made out of primarily hydrogen and helium, like the Sun. Saturn is nearly as large as Jupiter, despite having only 30% the mass. Three of the giants in our solar system (Jupiter, Saturn, and Neptune) emit more heat than they receive from the Sun. And all four giant planets have their own "planetary systems" -- their moons. In addition, it has been found that both planets and brown dwarfs can have eccentric orbits.

Currently, the International Astronomical Union considers objects with masses above the limiting mass for thermonuclear fusion of deuterium (currently calculated to be 13 Jupiter masses for objects of solar metallicity) to be a brown dwarf, whereas those objects under that mass (and orbiting stars or stellar remnants) are considered planets.[3]

So, don't fall for those hoaxes.

Originally posted by Truther
This is hopi indian prophicies, could this be the blue star there on about? you have to admit it does look blue also, if you see it from earth it looks blue..

I doubt it. Since it's main color is green, not blue it doesn't really fit. When it comes to signs and such, there was this little story I heard that I think is pretty fitting. It was actually in the context of debunking that Jesus being born of a virgin was some great sign, but I think it applies here as well. Hope I don't butcher it up to much.

Story goes like this.

This small town outside of Chicago was having a problem with their stop signs. The wind would blow so hard at times, that the signs would fall on the ground. This caused problems for traffic, as well as being a potential health risk if the sign fell on someone, or blew down the street and hit someone.

So the town decides to hold a meeting for the citizens to discuss how they can deal with this problem. Many ideas are exchanged, but none seem to really fix the problem. They are arguing back and forth to each other.

Finally, a little old lady stands up and says - if you want to fix them, then listen to me. All we have to do to fix the signs is bury them all in the ground. Then the wind can't get to the sign and they won't blow over. Problem solved!

Sound funny? It does solve the problem of the sign blowing over, so what is the problem? AHHHHH, because it's not really a sign if nobody can see it!

So I think this kind of falls into that same category. If it's described as blue, and then we see green, it's not the sign mentioned.


[edit on 24-2-2009 by badmedia]

reply to post by smokingman2006


My question is how does anyone know if a comet circles to come back through our line of sight....how.....i think it is a goverment cover up so that we do not see that we have the potential to be struck by any random debri in outer space and they say that its the same comet so that we are un aware of how many pass by us

Greenish tinghe may be due to it being copper based.

The comparison of 'Jupiter' sized is not the size of Jupiter actually, but the size of what we see as Jupiter as a planet in the sky. If you find Jupiter in the sky, you can then measure what size of light you will be looking for when looking for the comet. The comet will look as if it and Jupiter are the same size, putting off the same amount of light (or reflecting light) in the sky. The brightest luminary besides the sun is the moon, then comes Venus, then comes Jupiter...so you can look for the comet by comparing what you see when you look at Jupiter....if you find something brighter then Jupiter it is likely Venus and if it seems the same brightness as Jupiter and greenish...and in the right direction (Virgo/Leo) then you can find the comet.

Does that make sense?

I Apologize for typing the former posts without fully researching this. I have read a few different links just a few mins ago and it seems the comet is not as bright as Jupiter....but the atmosphere of the comet does add up to the same size of the planet Jupiter. It is somewhat confusing and it seems that the brightness of it is somewhat of a guessing game day by day. Some links say that you can see it with the naked eye and some say you cant. I will read up on this more....

But if you compare the comet and the atmosphere of the comet....it does equal to the size of Jupiter...literally.

So it'll be visible in the night sky in Britain...what about visibility in American skies? Any idea?

Originally posted by LeoVirgo
and it seems that the brightness of it is somewhat of a guessing game day by day. Some links say that you can see it with the naked eye and some say you cant.

Yes, there are often variations in brightness from day to day, as well as the gradual increase/decrease in brightness when comets approach/move away from us.

However, they are relatively small most of the time. A couple of years back, a comet named Holmes literally exploded in brightness (and size - of it's coma). It's thought this was due to a cavern collapsing. and ejecting huge amounts of dust/gas in the process.

Comet Lulin should be visible to the naked eye at the moment, however, this assumes that you have good observing conditions. If you are in a city or a town, the conditions are probably not good enough to make out objects that are around +6/+7 magnitude with the naked eye. However, you may be able to find it using binoculars or a telescope. Ideally get away from all sources of artificial light - well away.

Originally posted by starsyren
So it'll be visible in the night sky in Britain...what about visibility in American skies? Any idea?

Yes, see the last page for a chart that was posted. Hurry though, as it is likely to dim from now on, having approached earth, it's now moving further away.

Don't expect to see much more than a fuzzy ball through binoculars or a telescope, and with the naked eye, it just appears to be a dim star.

reply to post by expatwhite


It's atmosphere is as large as Jupiter.. gasses and dust and such. The Article says it's also shedding 800 gallons of water a second, which to me seems odd... a comet with water?

About a year ago my wife was driving down the highway in missouri and thought she saw something green falling to the earth could it have been a piece of this lulin comet.

Originally posted by Rockpuck
The Article says it's also shedding 800 gallons of water a second, which to me seems odd... a comet with water?

Did you not know that it's thought that comets brought most of the water we have here on earth?

Comets, trans-Neptunian objects or water-rich asteroids (protoplanets) from the outer reaches of the asteroid belt colliding with a pre-historic Earth may have brought water to the world's oceans. Measurements of the ratio of the hydrogen isotopes deuterium and protium point to asteroids, since similar percentage impurities in carbon-rich chondrites were found to oceanic water, whereas previous measurement of the isotopes' concentrations in comets and trans-Neptunian objects correspond only slightly to water on the earth.

Source: wikipedia

Or, rather, it was, but now it seems that asteroids are the likely source of most of our water.

can i see this if i look out side at 1 am on tues or wed on the east coast


is 1 am the correct time for east coast viewers????

reply to post by TheRealDonPedros


Thanks so much for that info. I've always loved astronomy but this particular comet has caught my attention for more personal reasons. I hope I'm not being too self centered or "mushy" but let me explain.

This comet is important to me because of the colors incorporated in it and where its located. My Dad passed away recently (god rest his soul) his favorite color was blue. My favorite color is green. To my understanding comet Lulin is currently directly under the constellation Leo (which is my sign) at its brightest from Earth. Add to that the fact that this comet is very rare.

I just feel compelled to get a look at it in real time for those reasons. I'm sorry, I just couldn't help but to lay that out there.

reply to post by smokingman2006


I was wondering what people were talking about. I will have to check it out tonight if you can still see it. Thanks!