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Oldest material on Earth discovered

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ESA/Hubble/NASA/Janaína Ávila

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Some of the pre-solar grains in the Murchison meteorite (inset) could have come from evolved stars similar to the Egg Nebula (pictured)

Scientists analysing a meteorite have discovered the oldest material known to exist on Earth.

They found dust grains within the space rock – which fell to Earth in the 1960s – that are as much as 7.5 billion years old.

The oldest of the dust grains were formed in stars that roared to life long before our Solar System was born.

A team of researchers has described the result in the journal Proceedings of the National Academy of Sciences.

When stars die, particles formed within them are flung out into space. These “pre-solar grains” then get incorporated into new stars, planets, moons and meteorites.

“They’re solid samples of stars, real stardust,” said lead author Philipp Heck, a curator at Chicago’s Field Museum and associate professor at the University of Chicago.

A team of researchers from the US and Switzerland analysed 40 pre-solar grains contained in a portion of the Murchison meteorite, that fell in Australia in 1969.

“It starts with crushing fragments of the meteorite down into a powder,” said co-author Jennika Greer, from the Field Museum and the University of Chicago.

“Once all the pieces are segregated, it’s a kind of paste, and it has a pungent characteristic – it smells like rotten peanut butter.”

This whiffy paste was then dissolved in acid, leaving only the stardust.

“It’s like burning down the haystack to find the needle,” said Philipp Heck.

To work out how old the grains were, the researchers measured how long they had been exposed to cosmic rays in space. These rays are high-energy particles that travel through our galaxy and penetrate solid matter.

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Janaína N. Ávila

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Scanning electron micrograph of a pre-solar grain. This example is around 8 micrometres long

Some of these rays interact with the matter they encounter and form new elements. The longer they are exposed, the more of these elements form. The researchers used a particular form (isotope) of the element neon – Ne-21 – to date the grains.

“I compare this with putting out a bucket in a rainstorm. Assuming the rainfall is constant, the amount of water that accumulates in the bucket tells you how long it was exposed,” said Dr Heck.

Measuring how many of the new elements are present tells scientists how long the grain was exposed to cosmic rays. This in turn informs them how old it is.

Some of the pre-solar grains turned out to be the oldest ever discovered.

Based on how many cosmic rays had interacted with the grains, most had to be 4.6-4.9 billion years old. For comparison, the Sun is 4.6 billion years old and the Earth is 4.5 billion.

However, the oldest yielded a date of around 7.5 billion years old.

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James St John

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The Murchison meteorite fell to Earth in 1969

More to be found

Dr Heck told BBC News: “Only 10% of the grains are older than 5.5 billion years, 60% of the grains are “young” (at) 4.6 to 4.9 billion years old, and the rest are in between the oldest and youngest ones.

“I am sure there are older pre-solar minerals in Murchison and other meteorites, we just haven’t found them yet.”

Previously, the oldest pre-solar grain dated with neon isotopes was around 5.5 billion years old.

The findings shed light on a debate over whether or not new stars form at a steady rate, or whether there are highs and lows in the number of new stars over time.

“Thanks to these grains, we now have direct evidence for a period of enhanced star formation in our galaxy seven billion years ago with samples from meteorites. This is one of the key findings of our study,” said Dr Heck.

The researchers also learned that pre-solar grains often float through space stuck together in large clusters, like granola. “No one thought this was possible at that scale,” Philipp Heck explained.

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Best shower filters for 2020: How they work and why you should get one

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If you already own a Brita filter to get rid of contaminants and sediment in your drinking water, you might want to consider doing the same thing for your shower water.

I’m willing to bet you’ve heard plenty of the concerns about heavy metals, asbestos, chlorine and other chemicals in our drinking water — and many of these worries are well-founded. Even cities in developed countries, including the US, struggle with polluted or toxic water, posing a serious health risk to the people who live there.

We don’t want to throw cold water on your at-home spa day, but as it turns out, a lot of these contaminants can be harmful in your bath water too. The good news? You can buy a shower filter for a relatively low price to protect yourself and your family from all the chemicals and metals in water.

Even if you’re confident that your water is quite safe to drink, a lot of people report that using a shower filter gives them healthier hair, softer skin, and helps fix all sorts of cosmetic annoyances.

You’d be surprised at the dirty contaminants hiding in your shower water.


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Lead and chlorine in drinking water

Even if your water smells and tastes fine, harmful chemicals could be lurking inside. Water pollutants fall into different categories, but the main ones of concern in your shower water are toxic metals, chlorine (used as a disinfectant) and the byproducts that chlorine creates with other chemicals in the water.

The main toxic metals that often hide in water are arsenic, lead, cadmium and mercury, which all made the WHO’s top 10 list of “chemicals of major health concern.”

Lead is often deemed as the biggest offender — water slowly corrodes the lead in home plumbing systems, and the toxic metal seeps into the water. Children are at a particularly high risk and have been reported to absorb up to 50% of their lead through drinking water. Even at relatively low levels, WHO reports that lead exposure can cause irreversible neurological issues. This is why water quality must always be a consideration.

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The lead from degrading plumbing can get into drinking water, causing all sorts of public health issues.


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Another main issue is connected to the chlorine that’s used as a disinfectant in our drinking water. The major health concern is actually the byproducts that are created when chlorine reacts with natural organic matter in the water, creating harmful chemicals called THMs. You’ve probably heard of chloroform, which is just one common THM, and high levels of THMs act as a carcinogen.

One study found that people absorbed more THMs from a 10-minute hot shower than from drinking a liter of water, so if you’re concerned about this, a shower filtration system that is actively removing chlorine can be helpful.

Are there toxic metals in your household water?

I hope I haven’t scared you into never touching your household water again. Many countries, including the United States, have a comprehensive set of guidelines to make sure that the harmful chemicals in your water, and your overall water quality, are being examined and regulated.

In the US, the EPA has legally enforceable standards for all different types of pollutants in your drinking water, as well as secondary concerns that may cause skin irritation or affect your hair. Your local water supplier should produce a new Consumer Confidence Report each year, and the EPA has a public database to easily look up the most recent report for your area. You can read the report and check if there are any worrisome pollutant levels in your water, but you can also rest safe in the knowledge that if any contaminants are over their legal limit, your area will certainly be notified.

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If you use public drinking water in your home, you can rest assured that it’s passing all sorts of safety tests.


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If you’re especially worried about lead, one easy way to mitigate that risk is to simply run the tap water a few minutes before using it. The most dangerous amounts of lead accumulate when the water has been sitting in your home’s pipes overnight, so if you flush that immediate water out, you’ll be in better shape.

Why you should buy a shower filter

If concerns about nasty chemicals in your water have already prompted you to filter your drinking water, you may want to do the same for your shower as well. Although your shower water is monitored to be safe in the short term, long-term exposure to heavy metals and chlorine is still a risk, especially for the very young and elderly.

Even if your water quality is perfectly safe, your hair and skin might still benefit from filtered shower water. For some people, the minerals and metals in their shower water wreaks havoc on their hair. Water with high concentrations of minerals is known as “hard water,” and it runs through the pipes in many people’s homes. Not sure if you have hard water? This USGS map can help.

Although it’s technically safe for consumption, you can easily find plenty of people who say that hard water wrecks their skin and hair, and that buying a shower filter alleviated sensitive skin, acne, frizzy hair and even eye irritation. Even more people say that a shower filter helped with itchy and dull skin, and flaky scalps.

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If you’ve ever experienced red, cracky skin, chlorine may be making it worse.


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It turns out that the reported effects of hard water on your skin are backed up by science. The specific minerals in hard water make it hard for soaps and shampoos to lather and do their job, so that icky feeling on your skin might actually be that it’s not getting quite as clean. 

A lot of the hair and skin irritation has to do with the fact that soap and hard water react to form “scum”, the white sticky layer left behind on your skin after soaping up. Have you ever noticed the white residue that builds up on your faucets that’s hard to clean? It’s the product of calcium and magnesium in your water, and that same residue is building up on your skin too. The scum clogs your pores and can cover the strands of your hair so that conditioner can’t do its work, making sensitive skin and high-maintenance hair worse.

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Hard water causes white gunk that piles up on your faucet.


Thrifty Fun

It’s not just the metals and minerals in water that dry out your skin. Anyone who’s spent time in a chlorinated pool knows how the chemical seems to draw all the moisture out from your body, leaving you with crunchy hair and red skin. The residual chlorine in shower water can create the same problems but on a much smaller scale, leaving you with skin that just can’t get quite as soft as you’d like. Keep in mind that the chlorine in water is hard to remove, so you’ll want to make sure the filter you buy is capable of removing chlorine.

How to choose the best shower filter for your home

Different types of filters work better to remove different types of contaminants and sediment, so you’ll want to check out what’s in your water and decide what’s most important for you when you’re looking for the best shower filter, whether that’s flow rate, water softening, shower filtration, or gallons of usage. Another thing to keep in mind is that while the initial purchase might not be that expensive, you’ll typically need to replace the filter or filter cartridge every six months. So, you should factor replacement filters and replacement cartridges into the cost too while looking at your shower filter budget.

Without further ado, here are all the shower filters to fit all shower types.

Sonaki

Activated carbon filters are the most effective choice for your shower head, and since this one is an inline model, you won’t need to buy a separate shower spray. The granular activated carbon removes bacteria, chlorine, chloramine (another disinfectant sometimes used), heavy metals, rust, and any other byproducts, so you can shower knowing that you’re safe. Plus, it’ll soften your filtered shower water so you can get softer hair than ever.

QwenchPure

KDF filters are made out of copper and zinc, two elements that create a small electrical-chemical charge between them. While it may seem counterintuitive to put more metal in your shower, a KDF filter is great for dissolving mercury, cadmium, arsenic, aluminum, and even chlorine. You won’t notice the electric charge in your shower, but the heavy metals sure will. This one too can be installed with any shower head, and will act partly as a water softener, getting rid of the hardness in your water.

Read more: Smart showers, smart toilets and smart sinks: Should you put your plumbing online?

Aqua Earth

A Vitamin C filter removes chlorine and chloramine fluoride by neutralizing it, but it won’t affect many other contaminants. If you have confidence in the safety of your water but chlorine gives you dry skin, a Vitamin C filter is a great way to go. The Vitamin C filter can also be attached to any shower head you already have.

Suncoo

At less than $10, this is the best shower filter if you’re operating on a tight budget. It mainly gets rid of chlorine, but the stainless steel mesh filter can dissolve some heavy metals as well. So if better skin and healthier hair are your main concerns when you take a hot shower, it’s a great choice. It comes in a chrome finish and with an extra filter cartridge. And, once again, this filter fits onto any shower head you currently use.

Reverse Osmosis Revolution

If the thought of pollutants in your household system is concerning to you or you live in an area that has contaminated water, you may want to consider whole house water filtration systems. This model has three water filtration layers — one with a micron sediment layer, another with granular activated carbon and a final carbon block filter, ensuring that just about everything harmful will be taken out of your water. So, you can enjoy using tap water from every faucet in your house without worry.

This article was originally published last year and is updated periodically.

The information contained in this article is for educational and informational purposes only and is not intended as health or medical advice. Always consult a physician or other qualified health provider regarding any questions you may have about a medical condition or health objectives.

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Calculating The Intrinsic Value Of Wholetech System Hitech Limited (GTSM:3402) – Simply Wall St News

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Today we will run through one way of estimating the intrinsic value of Wholetech System Hitech Limited (GTSM:3402) by taking the expected future cash flows and discounting them to their present value. This is done using the Discounted Cash Flow (DCF) model. It may sound complicated, but actually it is quite simple!

Remember though, that there are many ways to estimate a company’s value, and a DCF is just one method. If you want to learn more about discounted cash flow, the rationale behind this calculation can be read in detail in the Simply Wall St analysis model.

Check out our latest analysis for Wholetech System Hitech

Step by step through the calculation

As Wholetech System Hitech operates in the semiconductor sector, we need to calculate the intrinsic value slightly differently. In this approach dividends per share (DPS) are used, as free cash flow is difficult to estimate and often not reported by analysts. Unless a company pays out the majority of its FCF as a dividend, this method will typically underestimate the value of the stock. We use the Gordon Growth Model, which assumes dividend will grow into perpetuity at a rate that can be sustained. For a number of reasons a very conservative growth rate is used that cannot exceed that of a company’s Gross Domestic Product (GDP). In this case we used the 10-year government bond rate (0.7%). The expected dividend per share is then discounted to today’s value at a cost of equity of 9.6%. Compared to the current share price of NT$32.0, the company appears about fair value at a 4.9% discount to where the stock price trades currently. Remember though, that this is just an approximate valuation, and like any complex formula – garbage in, garbage out.

Value Per Share = Expected Dividend Per Share / (Discount Rate – Perpetual Growth Rate)

= NT$3.0 / (9.6% – 0.7%)

= NT$33.6

GTSM:3402 Intrinsic value, January 26th 2020

The assumptions

Now the most important inputs to a discounted cash flow are the discount rate, and of course, the actual cash flows. You don’t have to agree with these inputs, I recommend redoing the calculations yourself and playing with them. The DCF also does not consider the possible cyclicality of an industry, or a company’s future capital requirements, so it does not give a full picture of a company’s potential performance. Given that we are looking at Wholetech System Hitech as potential shareholders, the cost of equity is used as the discount rate, rather than the cost of capital (or weighted average cost of capital, WACC) which accounts for debt. In this calculation we’ve used 9.6%, which is based on a levered beta of 1.439. Beta is a measure of a stock’s volatility, compared to the market as a whole. We get our beta from the industry average beta of globally comparable companies, with an imposed limit between 0.8 and 2.0, which is a reasonable range for a stable business.

Next Steps:

Although the valuation of a company is important, it shouldn’t be the only metric you look at when researching a company. The DCF model is not a perfect stock valuation tool. Rather it should be seen as a guide to “what assumptions need to be true for this stock to be under/overvalued?” If a company grows at a different rate, or if its cost of equity or risk free rate changes sharply, the output can look very different. For Wholetech System Hitech, I’ve compiled three important factors you should further research:

  1. Financial Health: Does 3402 have a healthy balance sheet? Take a look at our free balance sheet analysis with six simple checks on key factors like leverage and risk.
  2. Other High Quality Alternatives: Are there other high quality stocks you could be holding instead of 3402? Explore our interactive list of high quality stocks to get an idea of what else is out there you may be missing!

PS. The Simply Wall St app conducts a discounted cash flow valuation for every stock on the GTSM every day. If you want to find the calculation for other stocks just search here.

If you spot an error that warrants correction, please contact the editor at editorial-team@simplywallst.com. This article by Simply Wall St is general in nature. It does not constitute a recommendation to buy or sell any stock, and does not take account of your objectives, or your financial situation. Simply Wall St has no position in the stocks mentioned.

We aim to bring you long-term focused research analysis driven by fundamental data. Note that our analysis may not factor in the latest price-sensitive company announcements or qualitative material. Thank you for reading.

These great dividend stocks are beating your savings account

Not only have these stocks been reliable dividend payers for the last 10 years but with the yield over 3% they are also easily beating your savings account (let alone the possible capital gains). Click here to see them for FREE on Simply Wall St.

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