Article summary: “A possible planet candidate in an external galaxy detected through X-ray transit”

R. Di Stefano, Julia Berndtsson, Ryan Urquhart, Roberto Soria, Vinay L. Kashyap, Theron W. Carmichael, Nia Imara.

1. Introduction

   One way to get a study of outer planets is obviously impossible through studies that we use in our own galaxy. That's why the brightest scientists decided to use X-ray sources ("XRS") in order to have better quality when they are made. However, outer galaxies occupy an infinitesimal part of the entire universe, and stars an even smaller part. For this reason, the study of the Universe with methods such as the measurement of radial velocity or the detection of transit means that hundreds of data that did not correspond to a planet outside our galaxy have been discarded.

   This is why everyone is surprised when in the galaxy M51, in a binary system, a very large source of X-rays is found and study begins.

   • This type of binary systems is a type of system that has nothing to do with our solar system.

     A neutron star is a body very similar to a black hole. The black hole is a place where it is filled with empty space. As a neutron star, it may be absorbing all matter so as not to leave gaps. So, in the system of the galaxy M51, where there is a binary star, it is formed by a normal star (20-30 times larger than the Sun, at 10,000 ºC) and by a neutron star, which has a force of gravity that like the neutron star absorbs matter, provides that the matter of the star that is at 5000 ° C, accelerates and is at 2 * 10 ^ 6 ° C. Which causes us to find a giant source that emits X-rays (electrons that are at 2,000,000 ° C cause jumps in the orbits of atoms, providing X-rays).

2. M51-ULS-1, X-ray

   We find that in this galaxy, there is a very large X-ray source (XRS). This binary system is provided with the star "M51-ULS-1". This star is almost in the centre of the galaxy along with other XRS "M101 and M104".

   The telescopes that were collecting data from this star (which were the Chandra and the XMM-Newton) observed that there was a drop in the brightness of this star during 10-12 ks, which provided create the study from the above methods.

   • - We are using two very powerful Chandra and XMM-Newton satellites (space telescopes) (European agency space telescope) that are designed to find supernovae or very powerful X-ray sources (very powerful bodies (found at millions of degrees)).

   This representation can be observed from the collected data transformed into graphs.

   

   

   From the Hubble Telescope, it could be observed that it was a type B2 star. At the same time, he was a star aged 6-14 years and giving very accurate data that the formation of this system is YES binary. Getting valid and secure information compared to “Pre-print-> M51-ULS-1b: The first Candidate for a Planet in an External Galaxy”

   • H-R diagram is used to know why it is a b2 star.

     The Hertzsprung-Russell diagram, this diagram is not normal, as the temperature decreases, observing the brightness (Y axis) and the type of star (X axis). They related luminosity to temperature, finding that there was a relationship between these two magnitudes. This diagram relates the luminosity, the size of the star, the chemical composition, the wavelength and its temperature.

   • Classification of stars, it is very important to know how it is.

     O, B, A, F, G, K, M, L, T, I. In relation to temperature.

     Within each type of star, we find 10 types. L, T, I, are the cold stars.

   We observe that we can compare X-ray curves with others in order to be able to make sure that we are not mistaken assuming the belief that it is a planet without comparison.

   This is thanks to the telescopes that provide us with information not only about the photons they receive but also about their type (Hard = H; Soft = S). We know that the energy change in the transition movements, in this case in the eclipse, must be minimal.

   As we can see in the graph of Figure 3, although there is a very large change in brightness, we do not find a large drop in intensity we find that the relationship between the number of soft (S) and hard (H) photons), quantified by the so-called hardness ratio (log 10 (S / H)) during transit is consistent with its out-of-transit value. Compared to that of the star M51-ULS-1, which although it does not undergo a major change in brightness, we do find the relationship affected.

   

   

3. The comparison of transit with donation-accretion of the system

   To know that M51-ULS-1b, is a planet in the galaxy M51 and is not the X-ray curve of the binary itself, so we have to deduce the main parameters of the curves. Once these parameters have been made, we can draw two conclusions about why it is a planet and not an X-ray curve of something else.

   As a first observation we have that the distribution between the radii of transit are comparable to those of Saturn.

   On the other hand, we have that the relative speed of transit between the transit and the source of X-rays is of 17 m * s ^ -1, which from some realized studies, arrives at the conclusion that it cannot be an internal X-ray since the transiting object (M51-ULS-1b) has a much larger orbit within the radius of the binary system.

4. The comparison of transit with donation-accretion of the system

   We may wonder why we look for so much information in galaxies so far away, because although we have very powerful telescopes like Chandra and XMM, it is not the main reason. Those galaxies located in distant areas are a good place to search for new information, as X-ray telescopes can take on a much wider field of view. In this way, collecting thousands and thousands of XRS (very powerful X-ray sources). As in the case of the galaxy M51.

5. The discovery’s form

   This article, in relation to your Prepress, aims to detail the smallest detail so that you can try to recreate this discovery so that you can clearly see the discovery that has taken place. In this way, this planet could be found from what we said before: the great source of XRS that was in the system. But within this pile of sophisticated formulas there is always a refutation of this theory given the infinite number of space bodies in the universe.

   The main theory was the belief of a white dwarf (WD), but it was refuted as its age does not correspond, however, we do not rely only on the age it may or may not have. But also by the gravitational laws that exist.

   Explain that white dwarfs when placed in the range of orbits produce an increase in light perceived by XRS, in reference to what has happened, on the contrary, is how the light has decreased.

   We can also eliminate the belief that it is a brown dwarf because through studies we can see in different graphs that the radii with which it can be compared are not the same resemblance as that of the M51-ULS-1b.

   

6. Future observations

   Although for now, the technology we are studying this planet of a galaxy (which is not ours) is being at very high levels of sophistication, there is always the likelihood that technologies and power will improve. reach unthinkable levels. Bearing in mind that apart from the X-ray source in the galaxy M51, it is only a small source of the hundreds found previously but not studied we can perceive that applying the same knowledge we can first find very similar planets.

   Still all this, new missions are known like the one of Lynx or ATHENA, that will provide a very great increase in XRSs.

   • Lagrange points and their importance for future missions with the most powerful L2 telescopes.

     Having two points or bodies that one rotates on the other, we find that there are certain points in balance. They are stable or metastable points in space where space forces are counteracted and centrifugal and gravitational forces are not there. The points are L1, L2, L3, L4 and L5. Where, for example, in L2, the James Webb (December 18) will be sent to be able to detect signs of life in external systems.

   • To detect life, detectors of Co2 (chemical component of respiration), Ch4 (produced by bacteria) O2, ...

   • It will also allow us to look at older places, such as the first stars after the Big Bang. Because if we are located in very distant places, we can see back in time, what will happen to the Webb. Previous place to which you can see Hubble. Being able to start deducing new theories about the multiverse, for example.

7. Conclusion

   Concluding with the information gathered by the two articles by Di Stefano et al., I can understand that the importance of X-rays, not only serve for medical terms, but also to be able to perceive the Universe in a different and more accurate way. Keeping in mind that it is not only important to read a finished article but also the one before it as you can always get data and information from the discoveries made in these articles which can be removed or not as defined as in this case.