One RGB Image Using Three Images

June 23, 2014

This is an RGB image using the infrared bands of Wise 1, 2, and 3. These three images are of the same size, so it works on the astropy package I am using without having to install Montage. I made 3 red, 2 green, and 1 blue. As you can see from all that red smudge, WISE 3 is sort of hazier. You can’t actually see a brown dwarf very well from WISE 3 band, so I guess this helps.

1-2MASS J00332386-1521309colorwise


Making Stars More Visible

June 20, 2014

Before I begin, there is a previous post that I would like to comment on my previous post. Apparently what I did was not combine three images and create an RGB image based on them. What happened instead was I put WISE 1, J, and K on top of each other, so all you could see was WISE 1 on top. Bummer. In order to do that, I have to install Montage, otherwise the images won’t rescale and stuff to fit each other. Unfortunately, it looks like a Linux kind of thing. Oh well.

Moving on to greener pastures, I have been changing a value called vmin and vmax. It allows me to set up a scale of color or black to white that depends on how bright the pixel is. So, let’s use the grayscale here for simplicity. If the pixel is as bright as the vmax value, then that pixel is white. If it is as dim as the vmin value, that pixel is black. In between it is all shades of gray. So, what happens, say if you bring the value of vmax down? The dimmer objects become whiter because now the brightness is closer to the vmax boundary. See here:

vmin_vmax

As you can see above, the bright object is still white when you lower the vmax boundary, but the whiteness becomes wider, while the dimmer object becomes whiter because it is closer to the line. That way, you can make dim objects stand out. See here two pictures below, one before the change, and one after:

1-2MASS J00332386-1521309-wise1

1-2MASS J00332386-1521309test

As you can see, it is much clearer that there is actually a thing shining right in the middle of the circle. I made the brown dwarf stand out.

 


Meaning Science Museums Are Ran by a Bunch of Cowards

June 16, 2014

This is what it has come to. A bunch of science museums afraid of teaching facts about climate change because of moneyed interests not wanting their playtime to end. And the chickens running those places won’t even take a stand. Disgraceful.


I Got Sent More Reading Materials

June 5, 2014

I don’t have anything particular to say about them. They are pretty much a technical summary of brown dwarfs found, classification of spectra, proper motion (angle speed in sky), and distance, which were found using the 2MASS survey and WISE telescope. You can read them here, here, and here, if you want to learn more about brown dwarfs. They are pretty technical, though.

Update: You know what? I was mulling things over, and turns out there are a few things I want to comment about. Firstly, there is a spectral classification cooler than the T type, called the Y type, which is characterized by absorption from ammonia. These brown dwarfs are cooler than 600 K. The articles above talk about some of those.

Secondly, the articles above have a large focus on high proper motion brown dwarfs. Higher proper motion implies that the object are more probable to be closer to us than those having low proper motion. Think about it this way, when you are in a car, things that are far away look slower than things that are closer to you. It’s not so much that in reality things that are farther away are slower, as it is the fact that things that are farther away has lesser angular movement because distances look smaller when farther away.

How are proper motion found? Well, turns out that the 2MASS survey took observations a decade previous to WISE telescope. So, you look at the pictures from 2MASS, and you look at one from WISE, and see how much the position has changed in angle. The objects are likely to have constant speed, so just divide the angle difference by the year difference.

What is proper motion helpful for? Well, it let us know that an object is likely to be close to the solar system. This is supposed to help bridge the gap in our knowledge of the solar system neighborhood. The distance itself can later be taken using parallax. Aside from that, finding close brown dwarfs is also helpful because it will help us study the atmosphere better. We still have an imperfect model on the process behind condensation and cloud formation in the brown dwarf atmosphere, and the more of them we find, the better we will know the details behind it.


The Point of My Research

June 2, 2014

I talked with my prof and got further information on what the point of the project is. It has to do with the Kepler space telescope. If you haven’t heard, two of its four wheels, which are used to point the telescope to a location, are broken, and so the telescope can’t maintain its sight to a position in the sky. Not only is there the fact that it is rotating around the Earth, the light from the sun has momentum. The light will push the telescope, and the irregularity of the telescope’s shape causes it to torque. The only way for the telescope to not be perturbed is to lie perpendicular to the sun. Unfortunately, that means that it can only observe in the plane of ecliptic, and it can’t maintain the same field of view throughout the year as the telescope has to maintain perpendicularity to the sun as the Earth orbits the sun. Nevertheless, useful science can be done. The telescope will observe certain fields of view, and when time is up, it will rotate again to another field of view that will maintain perpendicularity.

The point where my research comes in has to do with the way the above procedure means that the antenna is not facing the Earth properly. That means in order for them to continually observe an area in space, they will have to keep the information in the hard drive, and then send it back to Earth once the observation period is over. That means they have a limited amount of data they can store, and so the mission will have to be picky in which data they store. Looking for brown dwarfs to observe is supposed to help out Kepler in keeping . There are areas where not much brown dwarfs discovered, so what I am doing is helping that process out.

For now, I am just installing the astropy library for Python language. l will be looking at some picture of brown dwarfs, download them, and hopefully astropy can take those pictures and present them to me.

Source

http://keplerscience.arc.nasa.gov/K2/MissionConcept.shtml


The Power of Scientific Modeling

May 10, 2014

Scientific modeling is a powerful tool. Using the laws of physics, and computers if you want things to be much more convenient, you can predict how nature will behave and how it has behaved in the past. Recently, astronomers modeled the universe starting from 12 million years after the Big Bang, and let it run to present day, 13.7 billion years later. The result is what I would call beautiful. A great match between observation and theory. Here is a video by Nature journal explaining this:

As explained in the video, the simulated properties of the universe matches a lot with the properties of a real life universe, so we know that the laws of physics we have developed is in the ball park area of correctness. It is also explained that it is not perfect, and that is because even though we got a lot of it right, our knowledge of the universe is not perfect. That doesn’t mean science is wrong, it means it is incomplete, and we have to do more detective work in order to work out the rules of nature.

Here is another great match between data and models, this time between real life yearly average temperature and two models crunched by computers using the laws of physics. One of the models is temperature with human forcing of CO2, and the other one only includes natural factors. As you can see, real world data matches the one with human forcing, and it also “predicts” past temperatures very closely (shout out to badatronomy’s great post on climate change):

Another point of note is, all scientific models and measurements have uncertainties in them, but the data itself remains most of the time within the boundaries of the errors, so it is a good fit.

One of my favorites is the modeling of the ENSO without taking account of it. Meaning, you model the Earth with the ocean and atmosphere, plug in the laws of physics and various conditions, and ENSO will naturally occur in the simulation even though we don’t the exact mechanism for it. That is the predictive power of science.


This Is Why You Should Never Read Science From Regular News Media

March 18, 2014

Because they screw it up and spew misinformed drivel like Salon does. If they would have done a modicum of research, they would have found out the discovery is the sign of a gravitational wave embedded in the cosmic microwave background. This is more about the evidence for Alan Gurth, Andrei Linde, etc’s inflationary model, which covers up some of the unsolved gaping hole left by the big bang theory. Yes, the article does talk about the fact that it confirms inflation, but they always mix the facts up with some misinformation. As of yet, there hasn’t been any direct observation of gravitational waves. Not that it matters much because gravitational waves have been confirmed by indirect observations before even this one.  For example, by observing two neutron stars orbiting close to each other, they have found behavior that matches those predicted by the existence of gravitational wave. Seriously, research! Or am I asking too much for a reporter these days?


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