Take a look at the amount of fuel for star formation in the universe, compared to the number of stars, and you’ll notice something strange – there should be 10 times as many stars as there are. It’s a problem that has perplexed scientists, but now a study claims to have an answer, saying that the heat in star-forming clouds may be hindering stellar formation.They say that the temperatures are likely too hot to allow reasonable amounts of star formation, which leads to the observed lower number of stars we see in the cosmos today.
For a star to form, it relies on a cloud of gas to cool sufficiently so that it can gather into the large mass required for stellar formation.
In particular, intracluster gas – that near the centre of a galaxy cluster – is normally a prime region for stellar formation.
But just a handful of stars in are born every year in some galaxies, despite an abundance of this gas, so there must be something hindering the gas from cooling and forming stars.
‘The amount of fuel for star formation outpaces the amount of stars 10 times, so these clusters should be really star-rich,’ said Dr Michael McDonald, a Hubble Fellow in Massachusetts Institute of Technology’s (MIT) Kavli Institute for Astrophysics and Space Research.
‘You really need some mechanism to prevent gas from cooling, otherwise the universe would have 10 times as many stars.’
The theory proposed by the researchers from MIT and Michigan State University suggests a number of reasons for why this is so.
For some galaxy clusters, the researchers say, the intracluster gas may simply be too hot – on the order of hundreds of millions of degrees Celsius.
Even if one region experiences some cooling, the intensity of the surrounding heat would keep that region from cooling further – an effect known as conduction.
‘For these hotter clusters, they’re stuck in this hot state, and will never cool and form stars,’ Dr McDonald says. ‘Once you get into this very high-temperature regime, cooling is really inefficient, and they’re stuck there forever.’
He added that maybe, over tens of billions of years, they would cool down enough for stars to form.
Meanwhile, for so-called ‘cool core’ galaxy clusters, the gas near the center may be cool enough to form some stars.
However, a portion of this cooled gas may rain down into a central black hole, which then spews out hot material that serves to reheat the surroundings, preventing many stars from forming – an effect the team terms ‘precipitation-driven feedback.’
‘Some stars will form, but before it gets too out of hand, the black hole will heat everything back up — it’s like a thermostat for the cluster,’ Dr McDonald said. ‘The combination of conduction and precipitation-driven feedback provides a simple, clear picture of how star formation is governed in galaxy clusters.’ Dr McDonald also explained that, if a human were to venture into one of these hot clusters, they ‘probably wouldn’t feel hot, because the particles are very low density.’ ‘So the heat exchange between your body and the hot gas would be very slow,’ he added.’You’d likely be killed by the lack of oxygen and extreme low pressure much faster.’
Dr McDonald and his colleagues compared their theoretical framework to observations of distant galaxy clusters, and found that their theory matched the observed differences between clusters.
The team collected data from the Chandra X-ray Observatory and the South Pole Telescope – an observatory in Antarctica that searches for far-off massive galaxy clusters.
The researchers compared their theoretical framework with the gas cooling times of every known galaxy cluster, and found that clusters filtered into two populations – very slowly cooling clusters, and clusters that are cooling rapidly, closer to the rate predicted by the group as a critical threshold.
By using the theoretical framework, Dr McDonald says researchers may be able to predict the evolution of galaxy clusters, and the stars they produce.
‘We’ve built a track that clusters follow,’ Dr McDonald said. ‘The nice, simple thing about this framework is that you’re stuck in one of two modes, for a very long time, until something very catastrophic bumps you out, like a head-on collision with another cluster.’
The researchers hope to look deeper into the theory to see whether the mechanisms regulating star formation in clusters also apply to individual galaxies. Preliminary evidence, he says, suggests that is the case.
‘If we can use all this information to understand why or why not stars form around us, then we’ve made a big step forward,’ Dr McDonald said.
STARS FOUND FORMING ‘BELOW’ THE MILKY WAY
- Last month astronomers discovered stars forming in a remote region of the Milky Way not thought possible before.
- The stars were seen in a cloud of molecular gas 16,000 light-years below the flattened disc of our galaxy – further than any others ever seen.
- And if any planets were to form around these stars, inhabitants would see the entire glory of the spiral galaxy above them in their night sky.
- The amazing discovery – led by Dr Denilso Camargo of the Federal University of Rio Grande do Sul in Porto Alegre, Brazil – marks the first time that star-forming clusters that are part of the Milky Way have been found this far from our galaxy.
- ‘This is the first time astronomers have found stars being born in such a remote location,’ said Dr Camargo.
- ‘Our work shows that the space around the galaxy is a lot less empty than we thought.’
AMAZING FACT: GOD KNOWS HOW MANY STARS THE UNIVERSE HAS! He telleth the number of the stars; he calleth them all by their names -Psalm 147:4 (KJV).
Join us at: He Is Coming -Are You Ready?
Jesus Christ was born, lived, died, and rose again for the sole purpose of saving us from our sins. Are you saved? The bible declares that “For whosoever shall call upon the name of the Lord shall be saved.” – Romans 10:13 (KJV). Salvation is turning your life over to Jesus Christ, believing that Jesus is the son of God, and renewing your mind with his spirit, that is done through repentance of sin, and following JESUS with all your heart, mind and soul. JESUS transforms lives, if you are ready for this life saving step, call upon your savior TODAY! Learn more here.
And I will shew wonders in heaven above, and signs in the earth beneath; blood, and fire, and vapour of smoke (Acts 2:19 KJV).
And I saw a new heaven and a new earth: for the first heaven and the first earth were passed away; and there was no more sea – Revelation 21:1 (KJV).
For as the new heavens and the new earth, which I will make, shall remain before me, saith the LORD, so shall your seed and your name remain – Isaiah 66:22 (KJV).
Whose voice then shook the earth: but now he hath promised, saying, Yet once more I shake not the earth only, but also heaven- Hebrews 12:26 (KJV).
Nevertheless we, according to his promise, look for new heavens and a new earth, wherein dwelleth righteousness – 2 Timothy 3:13 (KJV).
BE INSPIRED – LEARN ABOUT THE STARS AND THE HEAVENS IN THE SCRIPTURES!
The heavens declare the glory of God; and the firmament sheweth his handywork- Psalms 19:1 (KJV).
I have made the earth, and created man upon it: I, even my hands, have stretched out the heavens, and all their host have I commanded -Isaiah 45:2 (KJV).
Thou, even thou, art LORD alone; thou hast made heaven, the heaven of heavens, with all their host, the earth, and all things that are therein, the seas, and all that is therein, and thou preservest them all; and the host of heaven worshippeth thee – Nehemiah 9:6 (KJV).
For the invisible things of him from the creation of the world are clearly seen, being understood by the things that are made,even his eternal power and Godhead; so that they are without excuse – Romans 1:20 (KJV).
Seek him that maketh the seven stars and Orion, and turneth the shadow of death into the morning, and maketh the day dark with night: that calleth for the waters of the sea, and poureth them out upon the face of the earth: The LORD is his name:- Amos 5:8 (KJV).
Lift up your eyes on high, and behold who hath created these things, that bringeth out their host by number: he calleth them all by names by the greatness of his might, for that he is strong in power; not one faileth – Isaiah 40:26 (KJV).
Which commandeth the sun, and it riseth not; and sealeth up the stars. Which alone spreadeth out the heavens, and treadeth upon the waves of the sea. Which maketh Arcturus, Orion, and Pleiades, and the chambers of the south. Which doeth great things past finding out; yea, and wonders without number – Job 9:9-10 (KJV).
…”Can you bind the chains of the Pleiades, Or loose the cords of Orion?” Can you lead forth a constellation in its season, And guide the Bear with her satellites? “Do you know the ordinances of the heavens, Or fix their rule over the earth?…- Job 38:31-33
There is one glory of the sun, and another glory of the moon, and another glory of the stars: for one star differeth from another star in glory. -1 Corinthians 15:41 (KJV).