Science News - July 2023

    If you ever took a general science class then you were probably told that the Earth gravity at the surface has a value of 9.81 m/s2 or 32 ft/s2. This is the gravitational acceleration you should experience at sea level of the surface and as you go up in height the gravity goes down following Newton’s law of gravity, or something along those lines. To an extent this can be used as true to make some calculations easy, like measuring the depth of a well if you were that kind of kid, or figuring out which object will touch the ground first, but as an adult now you may think that sea level is not an accurate representation of a distance from the earth’s center and that the feeling of the gravitational acceleration is different on different parts of the world, so the value is more like an average that you should experience across the globe, and this hold mostly true except for one area. 

    In the Indian Ocean there is an area of 3 million square miles where the gravity is so weak that the sea level is 106 meters lower than the global average. That is quite a huge difference that has puzzled scientists since 1948. Just for a little reminder the actual shape of planet Earth is not perfectly spherical, but more approximately like an ellipsoid with the poles being flatten down. For simple calculation in science classes we like to refer to Earth as a sphere as it makes calculations easier (trust me this is a common practice in physics when we are not considering accuracy), and the approximations hold up to a degree, but when precision and accuracy are quite important then those details arise and must be taken seriously to make adequate predictions and the use of Newton’s law of gravity is not as reliable and we apply some general relativity into the mix. Although it could be tedious, it is quite important work to keep in mind if you see yourself dealing with satellites as you will need to make adjustments to their orbit to remain up there, also to make GPS corrections,  otherwise they would end up crashing. Continuing with our narrative.

Map showing the variation of Earth's gravity. The color depict the strength of gravity, the blue dot over India is the gravity hole. Courtesy of ESA's GOCE Satellite (Insider).

    Officially known as the Indian Ocean geoid low, this region has been mapped using computer models of Earth’s gravity and compared with real data to try to understand how the anomaly came to be. After all such a big area could not be a mere coincidence.

    Scientists studying the anomaly have thought that something underneath was causing the strange effect, But a new study suggests that they should have been looking around, and not under, the gravity anomaly to solve the mystery of how it formed.

A team of researchers in India claims that the gravity hole was formed by plumes of low-density magma that rose up from Earth’s mantle generated 50 million years ago from a sunken tectonic plate.

    The new study was conducted using computer simulations at the Indian Institute of Science in the city of Bengaluru. They plotted 19 different scenarios to simulate the movement of the tectonic plates in the past 140 million years, and only a few of these scenarios account for the gravity hole but none of these scenarios showed the low gravity was caused by something directly underneath. Instead they found the hole was likely shaped by plumes of low density magma. 

    “As India separated from Africa and smashed into the European plate, the ocean that used to be there, called Tethys, was split apart and squished between the continental plates.”

    Future ocean surveys can confirm whether these plumes exist or not, but as of now this is the latest and more insightful explanation we have ever received to explain such an anomaly. Maybe this way of thinking can change the perspective on how to proceed with tectonic plates research. 

    If you want to learn more about this you can read these articles. 

• https://www.dailymail.co.uk/sciencetech/article-12282031/Indian-Ocean-gravity-hole-sea-levels-300ft-lower-experts-think-know-why.html
• https://www.advancedsciencenews.com/mystery-of-gravity-hole-in-indian-ocean-solved/
• https://www.businessinsider.com/scientists-crack-mystery-of-huge-gravity-hole-in-the-indian-ocean-2023-6
• https://www.usgs.gov/faqs/what-geoid-why-do-we-use-it-and-where-does-its-shape-come

    

Scientific Update

    I have tried to summarize the thoughts in my head for a while on the scientific news I have found recently. They may not be as recent anymore due to how long it has been since I read about them, and when I am posting about them, but they are still important, and I think they deserve more time in the spotlight. This has been a demanding task to do as life happens and one must deal with other stuff aside from just writing, but this is a task that I have chosen so here I have put my thoughts into a concrete script that I present to you now.

Water Hidden Under Earth’s Crust

    I found this information while searching for scientific breakthroughs a while ago. I like to see what news articles I can find and then proceed from there to search on scientific journals. The premise of this article is as follows:

    Scientists found that water is stored inside the mantle’s rock in a unique state, which is not a liquid, solid or a gas. This state is known as the fourth state (I am guessing is plasma water which I never thought about but I kind of want to create on a lab now).

    It all came from a rare piece of diamond found in 2022. When analyzed they were able to determine that this diamond originated 660 km or 410 miles beneath earth surface in the transition zone.

    The unique thing about this diamond is that it contained ringwoodite, a high-pressure phase of Mg2SiO4 (magnesium silicate) formed at high temperatures and pressures of the Earth's mantle, with hydrous phases which means it is rich in water implying that the transition zone is a wet zone, contrary to previous beliefs.

    It has been known that water can fall to the mantle through the tectonic plates and make its way back through volcanic activity in something known as the deep water cycle but this discovery is something else we did not expect. If this zone contains at least 1% of the total water then it implies that there must be more water than the one available in the surface, and if that is the case our models on how water appear on earth might need revisions.

    The team that made the discovery also found ferropericlase (Mg,Fe)O and enstatite MgSiO3, using X-ray diffraction and micro-Raman spectroscopy. This discovery aligns with another discovery made that the earth’s core is cooling down and it may be due to this appearance of water in the Earth mantle, but further research needs to be done on the subject.

 

Room Temperature Superconductor Research

    The next one I found it on a video on TIK TOK and decided to find the article and read it.  The article “Evidence of near-ambient superconductivity in a N-doped lutetium hydride” talks about the first ever discovered room temperature superconductor. If you are not familiar with the term, a superconductor is a material that can conduct electricity without any resistance. The reason why the wires get hot when you use a hair blower for an extended period of time, or your phone, or any other electrical device you may think of is because of the resistivity of copper and other materials to conduct electricity. This causes a loss of energy in the form of heat, but in the case of a superconductor this will not occur as electricity will freely flow without any resistance.

    MRIs, levitated trains, even the particle accelerator at CERN, are possible due to superconductivity, but as of now those devices depend on one big factor. To create superconductivity in materials such as mercury, lead, indium, and tin, the temperatures must be extremely cold, we are talking about 7 kelvin and lower, and they must be kept at that temperature because once the material starts to heat up it loses it superconductivity properties. Therefore, creating a material that sustains its superconductivity at room temperature has been researched for decades.

    During the experiment described in the article. The researchers squeezed together carbon and sulfur at extreme pressures, exposed them to hydrogen gas and shot it with a laser until a crystal substance was made and this crystal conducts electricity with zero resistance, a superconductor. This superconductor works at temperatures as high as 287 kelvin or about 15 degrees Celsius. While this is a great step in the right direction there is still a trick to this. The pressure at which this material can exist is about 267 gigapascals, two and a half million times the atmospheric pressure, so there is still a milestone to conquer. The interesting part about this article lies in the material used that made the discovery, nitrogen doped lutetium hydride (LuH2±xNy) indicating that new combinations of elements may hold the key to unlocking a feasible superconductor in the future.

The James Webb Space Telescope Has Done It Again 

    Finally, the one that knocked the socks off (figuratively) of many physicists in the last few weeks. My boy, once again, the JWST found what is being classified as the oldest known galaxies thus far. These galaxies date back to a time when the universe was only 2 percent of its current age, approximately 300 to 500 million years after the big bang.

    The discovery was made using faster photometry-based techniques that essentially use obvious variations in galaxies’ brightness to estimate their redshift rather than pining down cosmic coordinates to measure their redshift.

    The JWST Advanced Deep Extragalactic Survey (JADES) confirmed estimates for the four new galaxies. Of the four, the most distant is one with the name JADES-GS-z13-0. It has a redshift value of 13.2, meaning we are seeing the galaxy as it appeared just 320 million years after the big bang. 

    While the galaxies don’t yet pose problems for leading models of cosmology, they suggest galactic formation began earlier and proceeded faster than expected in the universe, this could revolutionize the field of cosmology and modification to the theory of the big bang may need to be made.

    Some science popularizers deem this discovery as the beginning of the end for the theory of the Big Bang, others simply claim that the model may need to make some adjustments, I think that it is just astounding to see how much the JWST has contributed to the field of cosmology and astronomy since its launch. This may create more opportunities for the field of astronomy and cosmology as more people get interested in learning about the new discoveries the JWST will continue to bring in the years to come.

    When I started this, I did not expect to find this many exciting news so often. People tend to say that science is dead and not many discoveries occur often as the news is constantly bombarded with other kind of news, but I keep finding interesting articles and discoveries every day, and as you see I have only covered the ones related to the field of physics and geology but there are more news in the fields of biology, chemistry and medicine that if I find anything that catches my eyes I will write about it.

To learn more:

• https://arxiv.org/abs/2303.08759
• https://www.quantamagazine.org/room-temperature-superconductor-discovery-meets-with-resistance-20230308/
• https://en.wikipedia.org/wiki/JADES-GS-z13-0
• https://arxiv.org/abs/2212.04568
• https://www.scientificamerican.com/article/jwsts-newfound-galaxies-are-the-oldest-ever-seen/
• https://www.natureworldnews.com/articles/56052/20230402/ocean-under-the-crust-massive-water-formation-found-beneath-the-planet.htm
• https://www.samaaenglish.tv/news/40031004

What the Future Looks Like for us

 

    In my last publication I talked about a comet that has not been spotted in over 50 thousand years. I hope you had the opportunity to see it. I got a small glimpse of it in the sky, and it was an experience I will treasure forever. Ever since then I found some great news in the world of science I wanted to write about; the upcoming solar eclipse in 2023 and 2024 (I should keep an eye on this). I attended a webinar about career for physicist that was very educational and interesting to know that the career path does not necessarily has to lead to academics, as a physicist you can find yourself working in many other places that find your skills useful. Finally, I found an article about how scientist at CERN made the most precise measure measurement of the second yet and it could lead to changing the number of hours in a day from 24 to 25 hours (Of course this was just an April’s fool prank, but it got me thinking).

    Unfortunately, I got caught up in work, sickness and other things that made it hard for me to sit down and write about it. It's not that I couldn't write it, I can sit and write about the rumors I heard or my personal thoughts on the matter, but I wanted to gather more information to provide a more compelled and truthful account of the articles I read, and not something superficial. To do this requires time because I have to find the articles, read them, verify the sources, ... and the task takes more than a few mere hours. I am very bad at managing my time. I always struggle finding time to do things I want to do, but I am working on this. So, I decided to change the approach of things. I will dedicate some time daily to reading scientific articles and creating a summary of them which then, I will compile into an article that I can use for publication here. You can read these summaries in my Twitter account where I will be posting daily, and you'll know when my next publication will be done.

    Also, I will be writing about the projects I am working on. Right now, I have started reading the book “Cycles of Time” by Roger Penrose and I will be writing about it as I go through it so you can see my progress. This book was recommended to me by one of my college professors a long time ago and although I have years with the book in my possession, I have never found the time to fully read it, my apologies to my college professor. Another cool project I found was in the YouTube channel of CERN lectures where they have small courses on some interesting topic, and I decided to give it a try so you may see writing about Quantum Computing which is the first course I will be doing. I may be doing other small projects and I will write about it so if you are interested in this kind of thing let me know in the comments.

    I am doing this to bring you interesting information about what real science is working on right now, not like those scientific demo shows that are made with the intention of popularizing and getting people’s attention by showing “cool science experiment”, this will be more realistic information and you may find this more appealing, hopefully. The second reason is to keep up to  date with everything that's going on as I consider is of vital importance for me as a scientist to keep up with what is happening in the world of science, what new discoveries have been made and what topics are research worthy, after all I plan of getting my PhD one day and I will need to have a strong background not just in physics but also in other areas. Hope you find this helpful and get you access to the latest in scientific news.

Follow me on twitter: https://twitter.com/JMDciencias

A Visitor That Took 50 Thousand Years To Return

    If you have ever looked up in the sky and wonder about the marvel of our universe, you form part of the thousands of year tradition that led human curiosity to explore the vast cosmos. In our exploration we have encountered planets, stars, galaxies, black holes, and comets. The latter being one of the most mesmerizing and rare events one could ever see.

    A comet is an icy, small solar system body that when passing close to the Sun warms and begin to release gases in a process called outgassing. Their icy center called the nucleus surrounded by a cloud of gas called the coma which is like a visible atmosphere. The ice is Regularly made of water (H₂O), carbon dioxide (CO₂), ammonia (NH₃) and/or methane (CH₄). They are a testament of the solar system early stages.

    Comets can develop two tails as they travel closer to the sun. the ion or gas tail, and the dust tail. The gas tail is created by the solar winds and the ice, it always points back from the sun. The dust tail is not affected by the magnetic field but is vaporized by the sun’s heat. Stargazers and astronomers enjoy the looking at the gas tails for its brightness and beauty while the dust tail to determine their trajectory.

Picture courtesy of NASA.

    Comets travel in Highly elliptical orbit starting out around Neptune or father away in our solar system in the Oort cloud. Due to their travel trajectory, they can end up leaving our solar system so they can become a one-time event.

    Among some of the most famous names we got the Halley’s comet which becomes visible to Earth every 75 years; Shoemaker-levy9 which was discovered in 1992 when it split and crashed into Jupiter, and the Hale-Bopp which was one of the most observed and brightest comets of the 20^th century. Some comets take hundreds and even thousands of year to complete their orbital period which is why when one is approaching people search the skies for the opportunity to see them. This year we got the opportunity to see a once in a lifetime comet that hasn’t been previously seen.

    Officially called C/2022 E3 (ZTF), this comet was discovered in March 2022, and it was determined that it would make it closest approach to Earth on February 1-2, 2023. What makes this comet so special is that the last time the comet approached Earth was 50 thousand years ago. A period where Neanderthal roamed the Earth. Unlike now the sky was much darker because they did not count with the technological advancement of electricity, so it is possible that Neanderthals saw the comet, but we have no records of this as it hasn’t been seen ever again since. The comet was visible to the naked eye during Feb 1-2 in certain regions of the planets but as it makes its exit you need a telescope to search for it.

    Unlike other comets this one is made of Diatomic carbon and cyanogen which makes it look green and it could be spotted near mars by Feb 10^th. If you miss it do not worry as advancement of technology has allow for recording of the comet to be made. Here I share one of the pictures taken of C/2022 E3 (ZTF).

Copyright Dan Bartlett.

    Comets leave behind black organic compounds when heated up that are studied as they may contain essential chemicals for life. There is the theory that comets may be the key to how life came to be on Earth. As they contain water and other resources essentials for life. In 2005, the Deep Impact Probe was launched to study the interior composition of comet Tempel 1. We await excitedly its return to see what we can learn from it.

    Comets are among some of the earlier remnants of the early universe. We can learn some much from them and they are also a beautiful sight to see. Being able to see one live is something you can tell your grandkids about.

2022 A Year of Breakthroughs

    At the end of every year people look for the most meaningful things that has happened to decide whether it can be considered a good year or not. After almost three years of battling isolation and Covid-19 we have finally returned to a more normal environment, and science has thrived because of it. 2022 marked a great milestone in many fields of science, so let’s take a look at some of the most iconic breakthroughs of the past year.

Nuclear Fusion Advancement

Image from the deparment of Energy of the United States.

    Our current nuclear power is based on fission, a reaction where a big atom is taken and broken apart and the energy released is used to heat up water that in turn powers some dynamo to make electricity. Nuclear fusion on the other hand aims to recreate the reaction that happens in the sun where small atoms are fused together to form a new bigger one releasing energy in the process.  Physicists started researching techniques and technology to recreate this process in the 1950s.

    Nuclear fusion is considered the “holy grail” of carbon-free energy, and with non-radioactive waste produced makes it the source of the future. For decades they have not been able to create the net energy gain required to make it viable. That is until now.

    The federal Lawrence Livermore National Laboratory in California reported that they had achieved a net energy gain in a fusion experiment using a tiny pellet of hydrogen plasma with the world's biggest laser. “ While the achievement is significant, there are still monumental engineering and scientific challenges ahead”, but it is a giant step in the right direction to feasible fusion reaction, although the public are more interested in the energy aspect of what this could mean considering the current fuel problem and energy consumption we are facing, this is an incredible achievement for science as fusion could help in the research of neutrinos detection and some other fields.

James Webb Space Telescope (JWST)

Image taken from the Nasa JWST website.

    On December 25th, 2021 the Ariane 5 rocket was launched from the French Guiana with the load of the JWST. A project that started in the 1990s as a substitute for the Hubble telescope but a numerous number of issues made the project delay over and over until it became an idea that never thought to become a reality. As soon as the launch took place, astronomers were excited to see what this telescope had to bring to the conversation so for the next few months the waiting was to fulfill expectations that were paid off on July 12, 2022.

    The first full-color images and spectroscopy were released to the public and the results were astounding. A comparison of the galaxy cluster SMACS J0723.3-7327 taken by the Hubble in 2017 and JWST in 2022 proved how the new telescope was indeed an upgrade over the Hubble telescope. Details never seen before appeared right away and people noticed that what they thought to be stars before turns out to be galaxies.

    Over the course of the year the JWST continues to explore deep space and the results and details are astounding. Some of the most notable images are the Carina Nebula, Southern Ring Nebula, Stephan’s Quintet, The Cartwheel Galaxy, Jupiter, Messier 74, the Tarantula Nebula, and so many more.

Life After Death

The heart, kidneys and liver are among the most needed transplant organs.

    Researchers from Yale University presented their results in what is considered a groundbreaking achievement for the future of organ donations. As of now the list of people that require organ donations is incredibly high across the globe and every year fewer and fewer people opt for becoming transplant donors. One of the reasons this is the case is because the transplant of organs has to be done while the person is alive, because cells become inactive once the person dies and the organs cannot be brought back anymore… or can they?

    In an experiment involving cells of dead pigs the researchers at Yale were able to see signs of functioning again in places such as the heart, liver, kidneys, and brains. The researchers hope the finding is a step in the effort to be able to make more human organs available for transplant long after death. Although it is still too early to say anything as the application is still very far away from use in humans, the results tell us that it will be a reality.

Universal Flu Vaccine

Representation of a universal vaccine.

    Every year the biggest enemy to health is the flu. We all at some point experience a strain of the flu even in adulthood. Flu shots are offered every year, but even those have proven ineffective most of the time as the flu virus is one of the fastest evolving viruses we have, and the number of different strains that exist around the planet is huge. With all this darkness and not seemingly solution nearby, a ray of light shined on us with the Covid-19 vaccine.

    When the vaccine for the coronavirus was announced it was an achievement that was hard to believe. The timeframe in which they were able to produce an effective vaccine against the virus left many people feeling doubt about the effectiveness of it, but it worked! This was possible due to a new technique using the mRNA of the virus instead of the regular method of inactivated or attenuated vaccine. mRNA vaccines work by introducing a piece of mRNA that corresponds to a viral protein, usually a small piece of a protein found on the virus's outer membrane. This allows the antibodies to immediately recognize it and be prepared for the future. The great advantage of this lies in that modifications of the virus does not greatly affect the effectiveness of the vaccine. This new technology makes the vaccine adequate for all strains of the virus. So, it was only a matter of time until this technology was used to attack the flu virus.

    Dr. Scott Hensley from the University of Pennsylvania designed a vaccine that included a virus protein from all 20 distinct influenza types. The vaccine has been tested on mice and proven quite effective in their first trial. Vaccinated mice produced antibodies against both similar and unique regions of all 20 different HAs, and levels of these antibodies remained unchanged for months after vaccination. This means that an universal flu vaccine is not that far away and it will be up to all of us to eradicate this virus. 

CERN Back In Business

    In 2018 the European Organization for Nuclear Research, known as CERN (from the French Conseil Européen pour la Recherche Nucléaire), was shut down for maintenance and upgrades, but after almost four years is finally back as the Large Hadron Collider (LHC) set up for a run 3 with an even higher energy threshold.

    The LHC is set to run 24/7 for the next four years at a record energy of 13.6 trillion electron volts. The upgrades should give the LHC tools greater precision and hopefully more discoveries about particles in quantum field theory. Some of the discoveries made at CERN are the W and Z bosons, creation of the first antihydrogen, discovery of CP violation, quark-gluon plasma state, and the Higgs boson. What can we expect from this new run of the LHC and what can be discovered at this new high energy level? We would have to wait to see.

Changing Asteroid Trajectory

Representation of the DART mission.

    Double Asteroid Redirection Test (DART) is a NASA space mission aimed at testing methods of planetary defense against devastating collision with a space rock. A probe was launched on 24 November 2021 and on 26 September 2022 intentionally crashed into Dimorphos, a minor-planet moon of the asteroid Didymos shortening its orbital period around didymos by about 32 minutes.

    The results of the cosmic collision are significant because it was the first real-life test of humanity's ability to protect the Earth from potentially catastrophic asteroids. The maneuver’s success suggests that with enough warning, asteroid deflection could be a viable way to save Earth from devastating collision and who knows what else.

Malaria Vaccine

A miracle that save lives.

    Malaria is a disease caused by a parasite. The humans get infected through the bites of infected mosquitoes.  People who have malaria usually feel very sick with a high fever and shaking chills. While the disease is uncommon in temperate climates, malaria is still common in tropical and subtropical countries. Malaria is one of the oldest known diseases on Earth and one of the deadliest killer diseases killing nearly one million people every year and infecting one out of 21 human beings on the planet.  Great efforts for the creation of a vaccine have been in the works for years but just recently in 2022 the first approved vaccine came into effect.

    RTS, S or Mosquirix as it is named, is the only malaria vaccine approved and in use. It requires at least three doses in infants by age 2 and reduces severe malaria and hospital admission by 30%. This once again seems like a small step but it is quite an achievement as it is the first effective vaccine in one of the oldest diseases we know.

A New Space Era

Artemis 1 mission patch.

    After a few months of delay due to fuel leakage, on November 16th, 2022, the Artemis program officially started. The launch was a success in starting the new era for space exploration. After orbiting the moon and deploying ten CubeSat the spacecraft returned to Earth on December 11.  This concluded the phase of Artemis 1 as a success and certify Orion and the Space Launch System for crewed flights beginning with Artemis 2 expected to launch in May 2024. The success of this mission will serve as the platform for future Mars human explorations.

Artistic AI

    You have probably seen the trend on Tik Tok or reddit, but the doors of AI have open to the public with new possibilities for businesses and households with text-to-image generators to “writing hallmark movie script” giving insights to artist, urban planner, and even reconstructive surgeons a helpful hand to visualize ideas. This is a great time to see how far artificial intelligence has come and what to expect for the future.

    More information about black holes, largest single cell bacteria, better batteries that do not depend on lithium, among many others are research that were considered groundbreaking in the past year. It was an incredible year for scientists, and I am thrilled for what may come in the upcoming 2023.

    If you want to learn more about the subjects here, feel free to read the following.

• https://www.washingtonpost.com/business/2022/12/11/fusion-nuclear-energy-breakthrough/
• https://www.ft.com/content/4b6f0fab-66ef-4e33-adec-cfc345589dc7
• https://webb.nasa.gov/
• https://www.smithsonianmag.com/smart-news/scientists-bring-cells-in-dead-pigs-back-to-life-180980557/
• https://www.science.org/content/article/innovative-universal-flu-vaccine-shows-promises-it-first-clinical-test
• https://www.nih.gov/news-events/nih-research-matters/using-mrna-technology-universal-flu-vaccine
• https://home.cern/news/news/accelerators/large-hadron-collider-restarts
• https://home.cern/news/press-release/cern/new-state-matter-created-cern
• https://www.sciencedirect.com/science/article/pii/S037026931200857X?via%3Dihub
• https://www.nbcnews.com/science/space/nasa-says-successfully-changed-asteroids-path-test-planetary-defense-rcna51738
• https://www.nytimes.com/2022/09/25/science/nasa-dart-asteroid.html
• https://www.wondriumdaily.com/malaria-the-deadliest-killer-disease-ever-known/
• https://theweek.com/in-depth/1019386/the-10-biggest-scientific-breakthroughs-of-2022
• https://jmdwonders.blogspot.com/2022/08/a-new-age-of-space-exploration.html

The Science Behind Grenades Explosions

    For the last couple of weeks, I have been playing the Uncharted series game. It has been quite a challenge to complete all the different difficulties the game has. As you increase the difficulty the accuracy of enemies shot and damage increase to a point where it feels totally unfair, but something that has struck me as unacceptable is how grenades work. Their range of explosion and their damage varies from game to game, and from difficulty to difficulty. I did not know much about grenades so I could not make a proper judgment, therefore I decided to do some research to satisfy my curiosity.

    The grenade I want to describe is an explosive weapon that is thrown by hand which is why it is usually called a “hand grenade”. What I did not know is that there are varieties in the grenade: fragmentation grenade which when explodes it spreads fragments. These are the popular ones, and the ones people refer to when they talk about grenades, shockwaves grenades which propagate a disturbance at high speeds to neutralize. Here you have stun and anti-tank grenades, chemical, and incendiary grenade use chemical reaction to create signals like a smoke bomb and crowd control like tear gas or set fire with temperature as high as 2,200 ℃ such as the famous Molotov cocktail.

    They are usually cylindrical in shape and of a size that fits in the hand of an average adult. They also have a time delay to allow the user to stay safe from the explosion.  In cartoons we often see the spherical design of grenades refer to as bombs. Those have a long match that indicates the time of explosion (as the picture below). It is also very popular in pirate movies. 

A cartoon bomb which in disguise is a form of grenade

    The match is used to activate the combustible material inside to set the grenade off. Modern grenades like the M61 (which is not as modern but still very popular) use this idea. This grenade has a safety pin which prevents it from unintentionally exploding. The user holds the striker lever and removes the safety pin which ignites an internal spark that sets off the combustible material to explode. The time delay is about four seconds.

Internal structure of a modern grenade.

    Fragmentation grenades usually can be thrown 130 ft of distance and have a harmful radius of 50 ft, that is about the radius covered by the shrapnel. So, let’s see, an ordinary grenade weighs about 0.9 kg and I want to say one piece of shrapnel weighs 0.005 kg (this is just a guess not an actual measurement). According to Wikipedia a classic hand grenade contains 50g of TNT. Since TNT contains about 4KJ/g this is an energy content of 200 KJ. One shrapnel can easily be traveling at a speed of 9 km/s, which will make it a dangerous projectile to anyone in the radius of explosion. Not only is the explosion that can cause you damage but getting hit by thousands of shrapnel can inflict injuries to anyone, not even being underwater will guarantee your security as you may find in movies, in fact water can be more dangerous as the water can served as a medium of propagation of the shockwave created by the explosion. 

    While playing the Uncharted games I threw a lot of grenades at enemies, and while they remained located less than one feet away from where I threw the grenade, they would continue to move as if nothing happened while when grenades were thrown to me, I suffered damage even while I was in cover. 

    Calculating the effects of a grenade involves a lot of data. You have to take into account how many shrapnel will be created by the blast, take into account the conservation of momentum, the combustible used to consider the energy released by the explosion, the material used to make the outer shell of the grenade. It is not as simple as counting its kinetic energy on release, there are a lot of physics principles that apply in this case. 

 

https://science.howstuffworks.com/grenade2.htm

https://aoav.org.uk/2021/what-is-a-hand-grenade/

https://www.youtube.com/watch?v=VoVNZGwOnZI

https://www.youtube.com/watch?v=W4DnuQOtA8E

https://en.wikipedia.org/wiki/Grenade

https://man.fas.org/dod-101/sys/land/m67.htm

https://physics.stackexchange.com/questions/500552/how-to-calculate-speed-of-shrapnel-based-on-explosives-speed-of-detonation

A New Age of Space Exploration

    On July 20th, 1969, hundreds of millions of people all over the world gathered around televisions and radios to listen to the words that mark what today we consider the end of the space race. 

    "Houston, ... The eagle has landed", "That's one small step for a man..." Are phrases that are well known across the world as humanity finally reached to land on the moon. I cannot imagine what that must've felt for the generation who got to live it, but I see its impact on society. Ever since that day, science has received massive support from governments and everyday more and more projects and proposals are created to push forward the boundaries of humankind.   

    The rocket Saturn V was the one responsible for all the six successful missions to the moon and now after years of development the Space Launch System (SLS) will carry the responsibility of the next generation going to the moon. If you are not familiar with it, the SLS is an American super heavy-lift expendable launch vehicle which is being developed in three major phases with increasing capabilities: the first phase denominated Block 1 will be carrying an uncrewed Orion spacecraft on a flight that should last approximately 8 minutes before reaching low-Earth orbit or LEO as it is known. From there on it will prepare for a Trans-lunar injection (TLI) to ensure that Orion will reach the moon and future missions that target deep space exploration. A TLI is a propulsive maneuver used to set a spacecraft on its trajectory to the moon. By increasing the spacecraft velocity, changing its orbit from LEO to a highly eccentric orbit, the spacecraft begins cruising on the lunar transfer arc, its trajectory approximates an elliptical orbit about the Earth with an apogee near to the radius of the Moon's orbit. With the right size and timing of the TLI burn the spacecraft targets the Moon as it revolves around the Earth. This first flight will mark the beginning of the Artemis program.

The Space Launch System block 1 Configuration.

    The Artemis program seeks to reestablish a human presence on the moon since its last time with Apollo 17 in 1972. This time the plan is to create a lunar gateway (sort of a small space station). The long-term vision of the program is to establish a permanent base camp on the Moon that will be used to facilitate human missions to Mars. 

    The first mission officially named Artemis I, will last for three weeks and will test all the rocket stages and spacecraft that would be used in later missions. After performing a TLI it will deploy CubeSat Satellites. These satellites will be used to test long-distance CubeSat communications technology, exploration of ice water on the moon using infrared, and some biological research.  According to plan, Artemis 2 will perform a crewed lunar flyby and will take place in 2024. Artemis 3 will perform a crewed lunar landing in 2025, the Artemis 4 docking with the Lunar Gateway in 2027 and future yearly landings on the Moon thereafter. After so many years of talks and exposition about colonizing Mars and creating a future where interspace flight is possible this mission will officially be the start of a new era. 

 On August 29th, 2022, NASA planned on sending their first rocket with a destination to the moon once more, but a leakage on engine 3 has made a delayed on this, so the next propose date is set for September 2nd.

If you want to learn more about this I suggest the following.

• https://www.nasa.gov/mission_pages/apollo/apollo11.html
• https://www.scienceandmediamuseum.org.uk/objects-and-stories/moon-to-living-room-apollo-11-broadcast
• https://www.nasa.gov/specials/artemis/
• https://www.nasa.gov/exploration/systems/sls/to-the-moon.html
• https://www.youtube.com/watch?v=_T8cn2J13-4&t=40s
• https://en.wikipedia.org/wiki/Artemis_1
• https://www.spacescout.info/2021/10/four-artemis-i-cubesats-miss-their-ride/