I am continuously amazed that prior to 1920, our accepted knowledge of the universe was that it entirely consisted of our galaxy, the Milky Way. This is not the distant past, such as when Copernicus placed the Sun at the center of the Solar System. We are talking about the post WWI modern era. I hope you agree with me that Hubble's discovery that there are more (lots more!) galaxies in our Universe and that they are receding from us was fundamentally a quantum leap in our conceptions.
Fast forward to 1990, and the launch of the Hubble space telescope. I am ashamed to admit, that from around that time, all I remember of the Hubble telescope is a cartoon showing us fitting it with prescription eye glasses, when a mission was sent up to correct its lenses.
But years later, thanks to the images generously shared by NASA and others, we have seen that the images of the universe have been beyond our imagination. My favorite picture, and I am assuming, a generally favorite picture, is the 'Pillars of Creation' picture of the Eagle Nebula some 7,000 light years away from us - with a picture of new stars being formed.
By far, the most stunning discovery made by the Hubble with the nearly 50,000 pictures it has taken is the Ultra Deep Field image. In a daring decision in terms of using the precious time of the Hubble, it was pointed to the darkest region, even for Hubble which is above Earth's atmosphere. And kept pointing at that very dark spot for a very sustained period of time. And hey presto! 10,000 galaxies were discovered! And these from 13 billion years ago.
We are now knocking at the door of the Big Bang. Hubble has taken us as far as 13 billion years and our estimate of when the Big Bang took place is 13.7 billion years.
Since the mid-90s a worthy successor to the Hubble is being planned. The Jim Webb space telescope, named after NASA's second administrator who oversaw the Apollo space program (ah, the romance, just at the thought of the Apollo program!)
The Jim Webb space telescope is larger, going to be placed farther, and is going to be taking pictures in the infra-red spectrum. The farther an object is, the light from it is more in the infra-red part of the spectrum by the time the light reaches us. So with Jim Webb's infra-red capabilities, we will be able to penetrate past the 13 billion mark set by Hubble and get very very close to the Big Bang.
The mirror based telescope is more than six times the size of Hubble's lens. And the screens that will shield the instruments from the sun are the size of a football field.
The mission is expected to launch in 2018. Here is wishing the JWTS world-wide team all the best. The Apollo missions, the Space Shuttle launches, the Hubble have all been amazing scientific, technological and managerial leaps. The Jim Webb mission is as grand and as epoch making as those. We are potentially on the cusp of redefining our understanding, as much as it was re-defined when Edwin Hubble first peered through the Hooker Telescope on Mt. Wilson, CA.
I have high hopes for the Jim Webb Space Telescope; and even bigger dreams!
Fast forward to 1990, and the launch of the Hubble space telescope. I am ashamed to admit, that from around that time, all I remember of the Hubble telescope is a cartoon showing us fitting it with prescription eye glasses, when a mission was sent up to correct its lenses.
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| Pillars of Creation |
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| Hubble Ultra Deep Field |
We are now knocking at the door of the Big Bang. Hubble has taken us as far as 13 billion years and our estimate of when the Big Bang took place is 13.7 billion years.
Since the mid-90s a worthy successor to the Hubble is being planned. The Jim Webb space telescope, named after NASA's second administrator who oversaw the Apollo space program (ah, the romance, just at the thought of the Apollo program!)
 |
| The JWST |
The mirror based telescope is more than six times the size of Hubble's lens. And the screens that will shield the instruments from the sun are the size of a football field.
The mission is expected to launch in 2018. Here is wishing the JWTS world-wide team all the best. The Apollo missions, the Space Shuttle launches, the Hubble have all been amazing scientific, technological and managerial leaps. The Jim Webb mission is as grand and as epoch making as those. We are potentially on the cusp of redefining our understanding, as much as it was re-defined when Edwin Hubble first peered through the Hooker Telescope on Mt. Wilson, CA.
I have high hopes for the Jim Webb Space Telescope; and even bigger dreams!
5 comments:
Yeah, this will be awwwwwesome! And after we’ve been shook by that awesomeness, we then tend to philosophize
Good stuff!
i was reading on a similar subject recently, a few things appeal to me.
1. The universe we see around is not what it appears to us to be. Some times we are seeing stars which stayed out there 13 billions years back. Today they may have burnt themselves out, might have exploded and disappeared or turned into black holes etc.
2. Some galaxies / stars which may lie behind black holes may be seen reflected many times by us due to lensing effect of black holes or heavy bodies not emitting any more light.So we won't know if there is one star which is seen by us many times over or are there really many?
3. Singularities seem to defy imagination and every physical law known to us! We are only guessing about it based on what is happening around the event horizon which is far far off the singularity.
4. Each galaxy looks like a the sangu-chakram we used to light during Diwali ! It sort of resembles the expanding space and time in its concentric outward spiraling structure from the larger side and very peculiarly extends far off from this point only to turn around and reach the same point by an invisible inwardly folded structure. Can this be a hint on how the big bang gets reversed or the process by which black holes are formed in a big crunch?
Greatly enjoyed your reply. Exactly how I feel!
Indeed, we are looking back in time, and since the light is from that many billions of years ago, they might be gone 'now', ie when we are examining that light.
You make a very very good point. This is like being in a hall of mirrors, except it is dark and very far away!
Our laws of physics that we have discerned seem to collapse here. We are only guessing now what this is. So much more to go in terms of learning.
The multi-verse theory posits that one universe could pop out of the other.
One thing, after thinking about all this, that I can agree with your earlier points is, just because we can see something and observe and measure it, does not mean we understand it.
On the other hand, just because we don't yet understand it, does not mean we stop observing and measuring.
But any, here is all the best to the Jim Webb team!
This is excellent.
My problem with the Big Bang is this. As of now, the whole universe is started with a big bang. But if there are more universes ( as it is accepted now) How does this big bang theory fit into it ?
It is difficult to think that many universes have started with the same big bang.
Also, hydrogen is supposed to have condensed to such an extant that it exploded to form the universe. So, is this hydrogen spread all over or concentrated at one point ? There are many more questions associated with it.
However, the progress made by man over centuries is indeed remarkable. But again as I have mentioned, why 'man' who is an insignificant entity in a cosmic scale, given this enormous opportunity and ability to explore the universe ?
We may never know the answer to it.
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