stars

How to! 4) Go stargazing for the first time

Hi,
since I went out stargazing couple of times already, I would like to mention few things here for you, when you decide to go alone or maybe with your boyfriend/girlfriend stargazing. While I live on northern hemisphere all of these tips will be useful to south people.

Preparation

Check out the time when the sun sets where you live. This page is quite useful for that, you just need to insert your location.

It is quite useful to know what these terms mean, astronomical dusk is what you are looking for.

So you need to watch out for the time when first stars/planets appear which will be some time after the dusk, of course there must be clear sky which you need to check on Google forecast [1] or in TV.

Then while it depends on the time of year, it is good to take some extra clothes, because most probably you will be standing still for some time, so you might get cold.

How to stargaze

First option: take some sky map on paper with you. You can print some from internet but check if you are printing the right hemisphere. For this, you will need also some light, but not white, since you would never build night vision, take red, eyes are not so sensitive to it.

Second option: take your smartphone and download application with stars, I use Star Walk 2 Free and it is pretty good, especially because there is option for night vision so it is red, this is very useful though you must never lock your phone, because when you want to use it again the light from you display would pretty much destroy the night vision you build up.

What is night vision anyway? It is the activation of all your non color sensors in eyes and the adjusting of your vision in darkness by enlarging the part that collects light, it take about 30 minutes though you may see the effect even after 4 or 5.

Pick a good location

Be sure to pick a good location. If you are in big city, than make sure to drive to countryside because the light pollution would just waste your time.

Best is hill though it is good to be on some field or place where there are no trees.

Keep away from any buildings and streets. It is important for you to keep the night vision, one single mistake when you look in street light could destroy the whole process.

Enjoy 😉

Dragallur

PS: it is better to go stargazing when there is new moon, otherwise, full moon spoils the view of huge part of sky.

[1] To get in Google forecast just type “weather” and “your location”.

Altair, Award, Dreams!

Hi,
For last (edit: first 😀 ) I decided to create second blog, do not worry it will never ever step into way of this one which is main and means a lot to me.

What is it about? It is about dreams, more accurately, lucid dreams which are dreams I want to learn to dream. Are you confused? Well then you will have to check out the blog and follow it too 😉 !

The posts there will be sometimes frequent sometimes not but I will continue to post every other day here, as I promised.

Make sure to check it out!

Today I was doing some work in school with different Wikipedia pages. I picked Altair which is pretty interesting star so I wanted to share with you what I found out.

Altair is 12th brightest star and it is located in constellation of Aquila.

Aquila

The area of constellation of Aquila in the sky.

It is one of the closest balls of plasma around, 16 light years. Its spectral type is A and it is brighter and bigger than Sun. What is als interesting is that it rotates quickly, one turn in 9 hours compared to 25 days for Sun. This is important for its shape since as it rotates the shape of the star changes to ellipsoid or “stepped on” ball. This has very interesting effect, the poles are brighter because of gravity darkening. The surface gravity at poles is greater making them brighter.

I have got award again, and again Versatile award which I had about week back or so.

I was nominated by mliae, thanks a lot. I would be happy to fill it but I nominated my most favorite blogs in recent awards already and I would not want to spam them again so for now I will just keep it for myself (do not take it as that I do not appreciate it, I do). 🙂

 

Dragallur

 

 

Creationism vs Science: The concept of God

Hi,
today I want to write about the concept of God. While this has really really long history and I can not even imagine how many people already thought about this, I am going to write about it from my point of view. Mostly what I learned from the conversation which I mentioned earlier.

So what is going on here? Why God exists in human minds in the first place?

Religious person would say that it is because of God that we think about Him. I mean, it would be a great coincidence that most people throughtout the history would belive in God/Gods even if they never heard about the other culture. There are actually so many religions and all of them (as far as I know, which may not be so far) have some higher being who controls everything.

So either I must admit that there is God because it would be too random otherwise, or think of another argument, why would somebody invent religion and God?

I talked about this with my mum and she said that she thinks that religions appear because people need solution to their problems. With this I agree, take some person 2,500 years back. There are so many things in his life that she or he does not understand. The person is probably some kind of farmer as it usually happened back then and life runs for them while maybe even something interesting happens during those years, something they can not explain with their knowledge which is anyway basicly zero. Well but something actually can explain anything, it is the God. Such a farmer can say that God did it, suddenly he has no more troubles because if something he does not understand happens, he says that God did it and there is no problem with that because God is able to do anything. When some trouble comes then it is easily explained by God and you can pray so that it does not happen again, so religious people actually know so much more than the rest of us do, they have answers to anything.

While this is completely illogical from modern point of view, it seems to me to be a good reason for religions to exist and there are people who still believe in this concept of God, because anything can be explained by it. Take for example my argument against recent creation of Earth:

The fact that there are stars in various stages (proto stars, young stars, stars old as Sun, red giants and supernovas) proves that Universe is much older than 6,000 years old because all of those stages took at least tens of millions years to get to.

Simple as that, this argument seems to me really really strong but actually creationists are able to throw it down in particular way.

What they say to you is that some things were created by God in mature state. What this means is that 6,000 years back there was created: supernova, red giant and new stars as if they never needed to go through all those phases. There is no problem with this because God is ultimately powerful and He is able to do such thing.

What is wrong with this?

This is where falsifiability and testability comes.

When you say that there is God who created supernova so it did not need to “evolve” you will solve it but is it testable? No. You can not test such a thing and what should you think? Think that processes work as we see them now for all the time or that processes worked differently in the past and could even be created from nowhere. When we believe such a thing we add piece that is completely unncesary and it is based only on one ancient book called Bible in which it is written to be truth. So how do we know that it was not 1,000 years or 5 years or that even Universe could have been created last Thursday (this is called last thursdayism) we do not but if we believe in such a thing we wont get anywhere, again I am returning to what I wrote about in last post and that if we teach creationism as truth in schools (while I think that we should at least mention its concepts), we wont get anywhere.

So does God exist? We do not know, it is simple as that. We know that creationism is wrong as I will probably proof in some future posts but science just can not say anything about God. Maybe He exists but right now it does not really seem that He has some real effect on our life, if the effect is that we have a Bible than He is being pretty manipulative.

I will also get to arguments by people who say that God is true because they can feel His existence and also near death experiences, though it will probably take me some time since I do not want to have a lot of such stuff on my blog and I will return to some astronomy and a real science.

Dragallur

 

 

 

 

 

The Universe is enormous

Hi,
I was thinking what topic should I mention today and remembered that the Universe is huge, and it is so huge that we completely underestimate it (at least I think that I still do).

First I will turn towards our planet, the Earth.
Here the biggest misconception is the size of Africa, you see the problem is that in most maps of Earth which you will see is Africa in the middle. If you know little about geography you know that there is no way to perfectly put our planet to scale on map. There are some ways which will be more accurate than other but most of the time Africa is going to be smaller than other continents. continent_infographic-01 copy

OK, now compare this map above with the scale on your home atlas, Africa is going to look tiny probably with Greenland, Siberia and Canada huge.

Now look at the picture of Earth and Moon distance, they are so little, Earth would be able to fit there so many times!

Now, seriously, look at this amazing page: THIS You start with Moon which is wide as one pixel. Next you will see Sun which seems to be pretty huge. Now if you click the speed of light button you will start to move slowly to right. Oh my god, the speed is so awfully low!

On top of page you have the bar with planets so you can click on them and ride from one another, remember, it is TO scale, and after you drive through whole map they say: You would have to travel 6,500 more maps like this to get to something.

This is huge, we are from Sun only 150,000,000 km.

OK´, Sun is small, lets see why:
1st picture shows that Sun is big:

2nd picture, well Sun gets little smaller:

3rd picture is actually a whole different story:
Now here is the last to compare it all, with little bonus of Canis Majori:
Ok but all of this stuff is so freaking small compared to whole Milky way! The radio signal from Earth which traveled for tens of years is not even visible on map of Milky way!
You can fit Sun 1420 times next to each other inside VY Canis Majoris.
And  you can fit Earth like this 109 times.
This means that you can fit Earth 157,780 times inside VY.
The diameter of Milky way is roughly 140,000 light years. Where one light year is 9,460,730,472,580,800 meters.

This is 741,669,055,548 Earths for diameter of Milky way. 2,540,000 light years is the distance to Andromeda galaxy, the closest galaxy.

Virgo Supercluster has 110,000,000 light years. Easy. On the next picture from @HighTechPanda , you can see the comparison of largest galaxy to Milky way, enjoy!And last, observable universe has 93,000,000,000 light years in diameter.

Still so underrated.

Dragallur

Africa picture

 

How to! 1) Using stars to navigate

Hi,
here it goes, here it comes. Just because of random I just made another series which may not continue anymore but I don`t care I made it just for fun and today I will write about really practical skill if you dont know where the hell you are. You just have to know couple of things.

So I will start with the easiest skill which you probably already know.
It is always crucial to know the constant direction in which you want to walk. If you have compass it should not be a problem unless when you are in the mountains there may appear bubble because of different pressure and it wont disappear again so watch out for this because then it wont be so accurate.

So the easiest thing is to find Polaris or North Star on the northern hemisphere. It is one of the most bright stars and and also Polaris is exactly at the point around which whole sky is rotating so it will always be on the same spot as you can see on the picture with high exposure.


You can find it when extending the big dipper, which is very bright constellation, 5 times.

Polaris will always point to the north and it should rise as you go north and set while you go south. This concept is very useful when measuring your latitude.

For this you need something to measure degrees. I heard that your fist on the length of your arm is about 10° or you can use watch that are not digital because the difference Image titled Navigate by the Stars Step 4between two numbers should be 30°. If you are PRO then you will have sextant of course :D. You should measure 90° on poles and zero on equator.

To know your longitude it is a bit more complicated. You need clockwatch which has some time like Greenwich, just that you know where this time is. Then during day you will measure when the Sun is highest which can be almost anytime since your watch are not on the time zone where you are.

Then because there is 24 time zones you know that for one time zone there is 15° of longitude + you will add half hours or whatever you measured when was the Sun highest. Then you will know how much you moved to west or east. With the method of sextant you can easily measure where is your place on the Earth. I will make sure to try it when it will be clean sky to see how accurate it is. Anyway if you want this to be useful you have to check the map to see the coordinates of some cities.

But you can use any star to orient yourself!
Put two tall things about meter apart. Than line up the tops of the things with any star and wait to what direction it moves.

  • If the star rose, you’re facing east.
  • If the star sank, you’re facing west.
  • If the star moved to the left, you’re facing north.
  • If the star moved to the right, you’re facing south

Btw. for this last one thanks to wikihow article, I did not know that.Image titled Navigate by the Stars Step 8

Also on south to know south, use South cross. Line up the two stars that
are making the T and they should point Alpha Centauri, the closest star and Alpha Centauri points to south.
Dragallur

Polaris photo 1st and 2nd
Sextant photo and South cross photo

Stellar classification

Hi,
what you can see on the picture is extremely cool (hot actually) even that you don´t know it yet. It is called Hertzsprung-Russell diagram and I will try to explain it with the rest of Stellar classification.

So there is first thing I have to clear out: What is Absolute magnitude?
Absolute magnitude describes how bright is star. This of course depends on the distance from which you are looking. It is called absolute because of fixed distance of 10 parsecs (around 32.6 light years). There exists also apparent magnitude which is taken from Earth´s view.

This absolute/apparent magnitude is in logarithmic scale. This means that for every point in magnitude, brightness increases by x2.512. So for 5 points, brightness increases 100 times (2.512^5=100.0226), this corresponds to what was created in ancient Greece. Also it is important to note that negative means more bright.

Absolute magnitude is Y-axis on HR diagram (it can also be luminosity) while X-axis is spectral class or sometimes surface temperature.
Spectral class corresponds with surface temperature, mass, solar radius and its rareness.
There are usually seven types but on the picture you can see nine.
Those seven are OBAFGKM. Where O type is hottest and M coolest with lowest mass.
You can use mnemonic to remember it: Oh Be A Fine Girl (Guy) Kiss Me (I really like this one :D).

And the last thing you need to know about the diagram are those roman numbers. Those are luminosity classes.
VII: those are white dwarfs.
VI: subdwarfs
V: main sequence stars
IV: subgiants
III: giants
II: bright giants
Ib: less luminous giants
Ia: luminous super giants
0: hyper giants! (those are shown on the right picture, blue line is orbit on Neptune and those stars are: blue hyper giant, yellow hg., red super giant and red hyper giant)

So now we can take our Sun and find out what we can tell about it.
Wikipedia says that spectral classification of Sun is G2V.
G: it is spectral class (girl/guy)
on the diagram it is rather on the left and you can see it is yellow.
2: means that Sun is in the upper part of G spectral class, this is only for subdividing those classes where 0 is highest and 9 lowest.
V: (it is 5) this means that Sun belongs to main sequence stars.

Now you can easily find where it stands.
Another example could be 10 Lacertae a star in the constellation of Lacertae.
O9V is its classification.
O: (Oh) you can see it is a super giant but with “only” 9 so it is rather smaller and cooler super giant.
V: again this one is lying in the main sequence so it would belong to upper left corner of diagram.

That´s about it, if you ever check for any star, this classification can be extremely helpful for you.

Dragallur

Note that there is table for spectral classes (taken from wikipedia page stellar classification):

O ≥ 30,000 K blue blue ≥ 16 M☉ ≥ 6.6 R☉ ≥ 30,000 L☉ Weak ~0.00003%
B 10,000–30,000 K blue white deep blue white 2.1–16 M☉ 1.8–6.6 R☉ 25–30,000 L☉ Medium 0.13%
A 7,500–10,000 K white blue white 1.4–2.1 M☉ 1.4–1.8 R☉ 5–25 L☉ Strong 0.6%
F 6,000–7,500 K yellow white white 1.04–1.4 M☉ 1.15–1.4 R☉ 1.5–5 L☉ Medium 3%
G 5,200–6,000 K yellow yellowish white 0.8–1.04 M☉ 0.96–1.15 R☉ 0.6–1.5 L☉ Weak 7.6%
K 3,700–5,200 K orange pale yellow orange 0.45–0.8 M☉ 0.7–0.96 R☉ 0.08–0.6 L☉ Very weak 12.1%
M 2,400–3,700 K red light orange red 0.08–0.45 M☉ ≤ 0.7 R☉ ≤ 0.08 L☉ Very weak 76.45%

Civilizations: Kardashev scale

Hi,
I learned some stuff about fermi paradox and alien worlds in past few days so I will try to do my best in describing this stuff. I found it really interesting.

So there is scale which is called Kardashev scale. It is scale that describes civilizations by three levels: Type I, Type II and Type III.

Type I
It is type that we are heading towards. Civilization of type I should be able to use all the available resources on its home planet which means it could fuse hydrogen into helium by nuclear fusion or it could use antimatter-matter anihilation to create enormous amounts of energy and would use sunlight, windpower or waterflow in large scales.

Type II
Type two civilisation would need even more energy which would cause in using all or almost all energy created by closest star (Sun). This “thing” is called Dyson´s sphere because it surrounds star and collects its energy. There are different types of Dyson´s sphere like: ring or swarm which are not that effective.

Type III
It is only extension to Type II because that civilisation would be able to use the energy of whole galaxy or multiple galaxies by Dyson´s spheres. Also there are some things like white holes or quasars which would also create a lot of energy so this type of civilisation could use them.

There is also extension for IV and V type.
4th would use whole universe while 5th would be able to use energy from multiple universes.

Dragallur

4) Particles: Hyperons

Hi,
I will talk about hyperons. Hyperons are not fundamental particles because they are made up by quarks, like neutrons or protons.
(to see what are quarks check this post: https://dragallur.wordpress.com/2015/05/03/3-particles-quarks/)
They are in the group of hadrons. It is group of particles that are made up by quarks so in this group are also Pions which are in the smaller group of mesons.
Btw. mesons are particles that are made up by pair of quark-antiquark.
While hyperons are in the group of baryons = particles with three quarks.

So the strange thing about them is that they have to have one strange quark so they can be hyperons. The most “common” one is similar to proton or neutron because he is made up of up, down and strange quark and he is called Lambda. There are twelve of them with different combinations of those three quarks, one of them, Omega has only strange quarks.

Ok, thats about it. They have also attribute of really fast decaying because strange quark is not very stable so they can not be found except in Hyperon stars. Those are heavier neutron stars in which hyperons wont decay because they have no space and gravity will hold them.

Dragallur

Dwarfs

Hi,
I had little pause but now I am coming back.
Today I want to write something about dwarfs because I found them little confusing.
We are talking about dwarfs in Universe not Tyrion.. there are six kinds:

  1. Brown dwarf

    Brown dwarf is the only one which is not star. It is actually extremely big planet which almost made it for the size of star. This term is used because red dwarfs already existed.
    Scientist are not really sure when it comes  to the difference of planet and brown dwarf. Jupiter would have to be more than 50x larger to be brown dwarf.
  2. Red dwarf

    Red dwarfs are “cool” stars. For example Proxima Centauri, the closest star is red dwarf. Their mass has to be about 0.08 of Sun to 0.5 of Sun´s mass. Red dwarfs are extremely common in Milky way as most of stars are smaller than Sun. That picture shows red dwarf and it would be more orange if showed from smaller distance.
  3. Yellow dwarfYellow dwarf is not really a dwarf. It is star which is about the same size like our Sun. Its temperature on the “top” is about 5000 to 6000 K.
  4. Blue dwarfBlue dwarfs are kind of related to red dwarfs because they are just a stage in their live. When red dwarf uses almost all of its hydrogen it will need to equalize with gravity and for that he uses temperature which rises and from red color it will shine in blue. This stage is only hypothetical because red dwarfs lifetime is really long and this could not yet happen.
  5. White dwarfWhite dwarfs are stage of all stars which wont make it to neutron stars or black holes. They are about the size of earth but much denser. From white dwarfs supernovas can explode.
  6. Black dwarfBlack dwarfs are only hypothetical but it is almost sure that they will happen when time comes. They are the next stage of white dwarfs. Black dwarf should not shine anymore because it is cool. They should be also really hard to detect because of their black color.

    Dragallur

What is the life cycle of stars?

Hi!
Somehow I wanted to write something from universe… not really I am still sitting in my hometown so here it is:

Well, stars (as our Sun) DO have beginning and end as you probably heard already. It can have different length.
First of all there have to be material. I mean lot of material because as you know our sun is huge. (Sun is bigger that 90% of stars)
This material comes from other stars that are dead now and theirs material probably came up from Big bang.
There are extremely large clouds that are called Molecular clouds. In them is lot of stuff and mostly H2.
If there is enough stuff at one place (it is really dense) it can make up planet which is either stony or made from gas.
If there is enough stuff it will make even larger gas planet than Jupiter or Saturn.
At that point all of this H2 will be pulled toward the center with magnificent force. That will create heat because atoms will be brushing against each other. If there is enough heat termonuclear reaction will occur which will normalize that pull of gravity and whooo! we have new born star!
Termonuclear reaction will change Hydrogen to Helium. Helium is heavier so it will go toward center and just a little bit of Hydrogen will be left on the edges. If the star is enough heavy it will start to change Helium to Carbon or Oxygen (I think). It will continue with couple of rounds until there in the middle is Lead (Pb). Than it will never be able to go forward and the life cycle will kind of end. Few more termonuclear reactions will occur (That is called red giant because it will greatly gain volume and the it will lose it) but then gravitation will win and if that star was small (even like our Sun) White Dwarf will be the END.
White dwarf is only really dense and hot piece of stuff.
If it was heavier.
Neutron star (made of only neutrons) will be the next stage. It extremely dense thing with tremendous gravitational field.
The last thing which can happen is Black hole, you can read about them in one of my first posts, they are absolutely awesome!

Dragallur
PS: if white dwarf gains again enough mass because of some stuff from space it can heavily explode into Supernova