I recently went to my daughter’s school in order to make a 3 hour presentation about space. I took with me my laptop, a projector, photos, video sequences, illustrations and paper models on famous satellites and robots that human beings used during the Gemini and Apollo era back in the sixties and seventies. And believe me I was surprised by how much these 8 years old kids knew in advance!
One of the first questions that popped was, “What about comets, meteors and black holes?”. The kids where in need to know about the outer threats, a threat caused not by humanity itself, not by the nature on earth but about a threat coming from outer terrestrial flying objects within the inner solar system. They were fascinated on how threats from far away could cause such devastation. I tried to avoid scaring the kids by telling them about the consequences of these threats. I will tell you how I responded later.
Aftonbladet, a Swedish newspaper published an article today (Nasa kan inte skydda jorden – “NASA cannot protect the earth”) about space and this time in particular they thought of writing about NASA’s NEO (Near-Earth Objects) program. It is certain that the budget in the US is currently restrained within many levels of the departments in the government. It is rough times for US economy and that has a great impact for NASA projects as well. History repeats itself, if we bring up Apollo missions as an example. Been there, done that, dont need that anymore!
Despite threats from budget cuts, the NEO program actually made some remarkable progress. It takes a great deal of time and sophisticated equipment to detect, analyze and catalogue tiny objects in space and scientists need to re-analyze these objects several times in order to detect their velocity and direction in order to predict future movements near earth.
We also have to remember that astronomy’s terms regarding distances and time are enormous in comparison to the timeframes and distances used in daily life. When an astronomer is talking about “Recent events” then she could be talking about hundreds of millions of years back in time. Or the term “close encounter” would be if a rock passes far away and behind the path of our moon. Remember that Apollo ships took 4 days to reach the moon travelling at the speed of a bullet!
In history, impacts that threatened life on earth have actually occurred. It is confirmed and well documented both from Apollo expeditions and by scientists on Earth. We also know that these kinds of impacts ending life will with all probability occur again. The question is rather “when” than “if” and if we think statistically about the time between these events it is currently believed that they occur more or less 20 million years apart. Statistically and theoretically we are currently quite close to an impact event – but nothing is certain. It may happen in 100 years or in 1000.
Again, astronomy is dealing with vast distances. Outer solar system members, such as the gas giants Jupiter and Saturn, are our defence. Due to their large mass, stones are often pulled into their gravitational field before reaching Mars or Earth (ex. is Shoemaker-Levy 9 comet).
So all in all, things called “soon” or “close to us” are still very far away and most likely will not occur during our lifetimes.
Back to my daughter’s class: when I saw the importance of giving a good answer, I told them threats from these objects are not going to affect us during our lifetimes. And by the time humanity will face these threats our technology will be far more advanced and we will be able to deal with these rocks!
Enjoy the sight of Perseids that can be seen out in the summer night as we speak. They will only last for a couple of days and it is a beautiful event. Unfortunately the weather in the south regions of Sweden has not allowed me to see them yet.
- Aftonbladet’s news article (In Swedish) – http://www.aftonbladet.se/nyheter/article5636367.ab
- NASA NEO program
It was almost full moon (-1 day) and I was in big hurry to get a few shots of the moon surface before fog and clouds would set an end to this observing session. The results of this session were not up to my expectations but I hope for a cloudless and clear night for next time. The individual exposures were quite good considering the fog and small clouds that passed before the moon from time to time.
On the southern hemisphere of the moon you clearly see the Tycho crater named after Tycho Brahe, a Danish astronomer from the mid 15th century. It got a high albedo and the impact resulted in a crater which is quite recent in astronomical terms (108 million years ago). Samples from this crater were collected during the Apollo 17 mission which was the last manned mission to the moon.
Apollo 17 was unique in its way, partly because the first scientist (Harrison Schmitt) was onboard on a mission to land on another celestial object and also because of the lengthy moon-walks. The goal was to gather as many samples from soil and stones as possible.
One of the questions that often arise is, how is it possible that the moon is battered by so many impact craters while the earth does not reveal such landscapes? Scientists have come to the conclusion that earth does not look the same due to erosion and atmospherical and geological activities.
Today it is known that the moon had volcanic activity and also that the existence of the moon was a result of a great impact by another large celestial body that crashed into the proto-earth. This is proven by the fact that the moon and the earth share the same basic geological structure according to the samples gathered from moon’s surface during the Apollo space missions!
One of the most important things before an astrophotography session is planning. You can never go out shooting with your camera without being well prepared in advance. There is something however, that you can never predict – weather!
So here comes my critisism towards SMHI (Metereological Institute of Sweden).
There is no weather website that turns ou to be wrong 9 times out 10 than SMHI (http://www.smhi.se). I am totally disapointed by their forecasts for the weather in Scandinavia. And because of our unpredictable and hard mistaken summers in Sweden it is most crucial you get at least the forecast right. Not to forget about their lousy website and the services that demand a fee in order to subscribe e-mail or link their reprehensible forecast through a flash application which has large limitations and is badly designed.
Contrary to this primitive and lousy website you have the Norwegians who’ve made an effort in forecasting, website layout and usability. It is one of the best I’ve seen so far (conserning weather forecasts in Scandinavia). This is the page I’m sticking with from now on. http://www.yr.no
Sara and myself where about to walk to the grocery store when I asked her if by any chance it would be possible to spend this evening with an observing session. I wouldn’t normally have asked her if it wasn’t because it was our last night together before she would go visit some relatives in Stockholm for a week.
Around 10 pm I started carrying out the mount, tube, camera and all other instruments needed. It was about time to set mt sights toward Jupiter. A planet that fascinates everyone that knows a little about it. Apart from it’s size and beautiful colors few people think how important this gas giant has been for our lives and our very existense! Yes… Because Jupiter has acted as saviour for this pale blue dot (C. Sagan) many times. The gigantic gravitational field pulls all the garbage floating around there in the outer solar system towards Jupiter. In fact, Jupiter’s role is as big as the one assigned to our Sun.
Polar alignment kept me busy for the most part, even though a DLSR camera wouldn’t give the same results as a CCD webcam, and the only webcam I own is a CMOS one. Nevertheless, the result you see below and thanks to Sara we could enhance the colors pretty well. So the result of Jupiter with my EOS 300D Digital Rebel was actually good!
And it was time again to turn the telescope toward the closest star we know. The Sun. And this dwarf star is also the most fascinating! It shows us how other stars work, considering fusion, magnetic fields, solar winds and all other kinds of phenomena making scientists drop their jaws. He still surprises us to a moment of silence during the ending of the 11-year cycle to the moment of violence. “Here I am, and I am alive!”.
It felt like some sort of an instict to bring out my telescope that day without checking spaceweather.com. To my astonishment I saw two solar spots emerging to the southeast on the visible side and the photo to the left is the result. Unfortunately some hot spots appeared and I forgot to handle it.
The following image is an enlargement of the previous one.