One of the most spectacular emission nebulae in the visible universe is the Eagle Nebula.
This stellar nursery, once the home to the enigmatic Pillars of Creation, the Eagle Nebula can be easily seen using a low-powered telescope.
In the article on Eagle Nebula facts, let us learn about its location, it’s age and a lot more that will leave you surprised. Let’s begin…
Eagle Nebula Facts: 1-5
1. Unlike the Ant Nebula, which is a planetary nebula, the Eagle Nebula is an emission nebula. It simply means that this nebula glows because of its own light.
2. This nebula is located in the Serpens Cauda constellation in our Milky Way Galaxy. The study of this nebula has helped scientists to understand what really happens inside a nebula.
3. The person who originally discovered the Eagle Nebula was Philippe Loys de Chéseaux. He discovered the nebula way back in 1745-1746.
4. Actually, Philippe Loys de Chéseaux – the Swiss astronomer didn’t really discover the entire nebula. He only discovered the star cluster in the nebula.
5. It was Charles Messier – an astronomer from France – who, in June 1764, discovered that the star cluster that was discovered by Philippe Loys de Chéseaux was actually a part of a nebula.
Eagle Nebula Facts: 6-10
6. In his catalog, Messier cataloged his discovery as the 16th object. No wonder, the Eagle Nebula is today also known as Messier 16 or M16.
7. There are some other names of the Eagle Nebula. They are: “The Spire” and the “Star Queen Nebula”.
8. As far as the age of the Eagle Nebula is concerned, scientists believe that it is a little older than 5.5 million years.
9. The Eagle Nebula is so called because it looks pretty much like an eagle.
10. Basically, Eagle Nebula is the name given to an emission nebula called IC 4703, and the star cluster associated with it. So, IC 4703 + Star Cluster = Eagle Nebula.
Eagle Nebula Facts: 11-15
11. The distance of IC 4703 from our planet Earth is 7,000 light years. It is the active star forming region of the Eagle Nebula. The Star Cluster associated with the IC 4703 is known by the name NGC 6611.
12. Getting confused? No need to get confused. Remember this: IC 4703 (emission nebula) + NGC 6611 (associated open star cluster) = Eagle Nebula.
13. Just how big is the Eagle Nebula? Not much. Astronomically speaking, it is very small. It spans out over an area of 70 light years by 55 light years.
14. The IC 4703 (which is often used for referring to the Eagle Nebula) is made up of UV rays-emitting ionized gas clouds.
15. The open star cluster or the NGC 6611 is estimated to have 8,100 stars. The brightest star in this cluster is known as HD 168076.
Eagle Nebula Facts: 16-20
16. The HD 168076 is basically a binary star system where the primary star is O3.5V and the companion star is O7.5V.
17. The HD 168076 is extremely bright with +8.24 apparent magnitude. This makes it visible with a pair of good binoculars.
18. The HD 168076 is much bigger than our Sun and has an estimated mass of 80 solar masses. It is also 1 million times as luminous as our own Sun.
19. The star cluster NGC 6611 was what Philippe Loys de Chéseaux actually discovered. The age of NGC 6611 is estimated to be 5.5 million years while the nebula itself is estimated to be a little older than that.
20. The apparent magnitude of the entire nebula is +6.4. This is why a low-powered telescope is just sufficient to spot the Eagle Nebula.
Eagle Nebula Facts: 21-25
21. In the Eagle Nebula sits the Pillars of Creation – three finger-like projections running upwards.
22. These pillars were so named because of the huge number of stars that formed inside those pillars.
23. These pillars were, for the first time, photographed in 1995 by the celebrated Hubble Space Telescope. The people who took the photograph were Paul Scowen and Jeff Hester.
24. The Pillars of Creation in the Eagle Nebula were very much similar to Pillars of Star Creation in Cassiopeia constellation’s Soul Nebula. Interestingly, the Pillars of Star Creation is far bigger in size and they were photographed in 2005 by Spitzer Space Telescope.
25. The Pillars of Creation no longer exist. That came as a surprise after a new set of images were taken by XMM Newton and Herschel space telescopes from European Space Agency.
Eagle Nebula Facts: 26-30
26. The new images suggested that the pillars were actually destroyed some 6,000 years in the past because of a nearby Supernova Explosion that took place some 8,000 to 9,000 years ago.
27. We still continue to see the Pillars of Creation, because we are actually looking back into the past when we look into space. How is that possible? The quick explanation is given below:
We can see something only when the light reflected from the surface of the object reaches our eyes. It takes time for light to reach our eyes (however less it may be). So, basically, we are always looking into the past.
28. The Pillars of Creation sit at a distance of 7,000 light years from us. So, the image that we see today is actually the light that has been traveling through space for a period of 7,000 years.
29. Since the Supernova Explosion took place some 8,000 to 9,000 years back, the light from it had already reached earth some 1,000 to 2,000 years back.
However, the slow moving shock wave created by the supernova passed through the Eagle Nebula over a period of a few thousand years and destroyed the pillars.
The light from the period of actual destruction will reach us in another 1,000 years. So, we will be able to see the destruction of the pillars in about a millennium from now.
30. We saw the Pillars of Creation, but unless science achieves immortality, we will not be able to see the destruction. Our future generations may witness that, but by the time they see it, they will also be looking into the past and the event will have long gone!
Eagle Nebula Facts: 31-35
31. The results of the images taken by the XMM Newton and Herschel space telescopes were actually confirmed by Spitzer Space Telescope, which observed hot gasses suggesting that a supernova explosion did take place.
32. The Pillars of Creation may look tiny in images and even tinier with the Eagle Nebula in the background. Don’t be fooled though. They were big, really big. The tallest pillar that we see in images was as tall as 4 light years, which translates into 23,462,784,000,000 miles. Yes, that’s how tall the tallest pillar was.
33. Just to give you a quick understanding, the protruding head of the tallest pillar was big enough to nicely accommodate our entire solar system.
34. The pillars were composed of incredibly dense clouds of dust and gas. The extreme gravity and huge density of the pillars made the gasses and dust fuse together and form stars. Literally thousands of stars were formed inside these pillars.
35. The other interesting feature of the Eagle Nebula is the Stellar Spire. Sitting in the northeastern part of the nebula, this Stellar Spire is humongous.
Eagle Nebula Facts: 36-40
36. The Stellar Spire is 9.5 light years long. That is, it stretches out 90 trillion kilometers!
37. The spire is so named because it looks like a statue of a winged fairy standing on a pedestal.
38. The Stellar Spire is another area of rampant star formation. This spire is also made of cold dust and gas that come together to form what is known as EGGs or Evaporating Gaseous Globules, which are basically the sources of new stars.
39. This pillar or the Stellar Spire is also getting eroded from the top by ultraviolet rays released by young, hot and massive stars. One day, this Stellar Spire will also be gone just like the Pillars of Creation no longer exist today.
40. When the image of the Stellar Spire was released, many people said that they could see a humanoid-like figure in the pillar. But scientists clarified that it is called pareidolia or illusion that is caused by clouds inside a nebula.
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