The good and bad of Nextdoor

If you live in the US and a few other countries, you may have joined the group known as Nextdoor. It is a place where people can share information about their neighborhoods and get to know what is going on locally. Most of the time it involves lost and found pets, petty crimes, alerts, and requests for information and assistance. In that respect, it is useful and can serve to bring people in a community together around common interests. But as Andrew Anthony writes, like all social media, it has a dark side with people voicing stereotypical views.
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Tackling the problem of renewable energy storage

The cost of producing renewable energy using solar and wind has been dropping sharply over the years so that it is now comparable and often even cheaper that energy produced using fossil fuels. So why hasn’t it taken over the energy sector completely? The reason is that when it comes to renewable energy, there is an extra cost that fossil-fuel based power plants do not have and that is the cost of storing the energy and this has to be factored in as well.

It is energy in the form of electric current that drives all our devices but the problem with current is that it cannot be stored as current because as it flows in wires, it dissipates its energy as heat. (Superconductors don’t have any resistance and thus do not lose any heat but the commercial applications of that are far off in the future.) The production of current has to exactly match the use of current at every moment. The energy grid is is a true marvel of engineering technology that achieves precisely this. We have various power plants feeding electricity into the grid and this is the sent all over the area covered by the grid to wherever it is needed at that moment. So in the US during the summer months, for example, energy is sent to the hot southern parts of the country to meet the increased demands of air conditioning.
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A Pyrrhic victory for religious symbolism

While much of the week’s legal news has centered on the leaked draft of a US Supreme Court that revealed that a majority of the court have decided to overturn the Roe v. Wade decision that legalized abortion in the US, there was another ruling on Monday that has much less of a momentous impact, and that was the unanimous opinion that said that the city of Boston could not forbid the flying of a flag at city hall that had a cross on it.

The city of Boston violated the free speech rights of a Christian group by refusing to fly a flag bearing the image of a cross at city hall as part of a program that let private groups use the flagpole while holding events in the plaza below, the US supreme court ruled unanimously on Monday.

The 9-0 decision overturned a lower-court ruling that the rejection of Camp Constitution and its director, Harold Shurtleff, did not violate their rights to freedom of speech under the first amendment to the US constitution.
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Environmental racism

On the latest episode of Last Week Tonight John Oliver discusses how historic racial discrimination practices have resulted in poor and minority communities ending up living in highly polluted areas, where the life expectancy can be ten years below nearby communities that are not similarly polluted. He describes one community where the lead levels are hundreds of times above acceptable limit, so that signs are posted on yards telling children not to play on the grass or in the dirt! That is like asking children not to breathe the air.
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Trump and toilets

Seth Meyers had a pretty funny A Closer Look segment where he discusses, among other things, Trump’s obsession with low water flow from faucets and that toilets no longer flush properly.

I have no idea what Trump is complaining about. I never experience any of the problems that he describes and I don’t even live in the luxury world that he does. Meyers has a theory about why Trump is convinced that toilets don’t flush properly. It is because he repeatedly tries to flush documents down them, as aides have said.

Trump also has an obsession about windmills. He seems to spend a lot of time at his rallies talking about both. It may simply be that when he speaks at these rallies, he is on autopilot, just wandering through the various topics he has spoken of again and again, so that no new material or real thought is necessary. That may be why he forgets the names of the people he is supposed to endorse, even though the rally was held for that specific purpose.

What a weird, weird, man.

The problems with self-driving cars

Self-driving cars, like the AI technology they are based on, seem always to be just tantalizingly beyond our reach at any given time. I have been hoping that self-driving cars become a reality because I am getting on in years and there is bound to come a time when it will not be safe for me to operate a vehicle, even though I have been accident and ticket-free my entire driving career, except for one fender-bender and one minor infraction, both of which took place over three decades ago when I was young, wild, and foolish. (No, not really. Both were rather boring events.)

The loss of driving privileges can result in a deep drop in a person’s independence, especially in the US which has pretty bad public transportation services. Having a self-driving car would provide older people or those with any issue that prevents them from driving, from being housebound. Of course, these cars are initially likely to be expensive but over time the prices should come down. The catch is that even though these cars have improved tremendously, they still seem to be not ready for prime time.
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Does online advertising work?

As someone who spends way more time on my computer than is probably healthy, I am familiar with online ads because they bombard me all the time. We know that online advertising has been a huge wealth generator for those companies such as Google and Facebook that sell and place ad space and indeed is the source of revenue for any ‘free’ content on the internet. (This blog is the exception. It is genuinely free!)

The promise that the media platforms offer to ad buyers is that they can target the product to the individual buyer who may be looking for that particular item, thus preventing wasteful blanket ads. The way the platforms do that is by vacuuming up all the information they can glean from us from our online activity to create a detailed profile of each one of us that they can then sell to retailers, a process known as ‘microtargeting’. This promise of ultra-efficiency is what has led the migration of ads from print media to online media. It has also led to fears that that we are now living in a Big Brother world because our lives have become transparent to these big companies like Google and Facebook who seek every way of prying into our lives.
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Webb telescope instrument alignment completed

The last major step in the development of the Webb space telescope, checking the alignment of all the instruments, has been successfully completed and all the instruments seem to be at the correct operating temperature. NASA has released images taken of the Large Magellanic Cloud to show the clarity obtained.

The image shows snapshots from each of Webb’s three imaging instruments, plus its spectrograph and guidance sensor. The images show a field of stars in the Large Magellanic Cloud (LMC), a galaxy near the Milky Way about 158,000 light-years away. If it orbits our galaxy, it would be, by far, the largest satellite galaxy. But there’s a chance it’s just passing through or slowly merging with our galaxy.

Now that the imaging instruments are properly aligned, NASA and its partners will begin commissioning several science instruments. These are components within the imaging instruments that can do things like filter certain kinds of light, adjust the cameras to specific customizations, or apply a particular lens. That could take a few months, as could a few calibrations to confirm that the telescope is temperature-stable when it moves between targets. During that time, mission control will also monitor mirror alignment to make sure it stays in place.

NASA has also released a video of the event.

In a few months we should start receiving images of parts of the universe we have never seen before.

Lethal fruit

Donald Trump has been sued (again!) for inciting violence by urging his bodyguards and his supporters to physically attack critics and protestors at events that he attends. As part of the case, he had to submit to a legal deposition towards the end of last year and in the course of it, he expressed fears about reports that he might be pelted with fruit, especially tomatoes.

The Daily Show‘s Trevor Noah say that no comedy writer could match the quality of the humor in the deposition transcript and to prove it he and Michael Kosta read verbatim from the it. That five-minute segment begins at the 5:45 mark.


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