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Yes batteries can do this for a DC system like in your car. But that is mainly a voltage regulation function.

Power quality correction is a consideration in large industrial AC power networks. It helps with the problems that arise from running large amounts of electric motors where the power factor gets out of balance between inductive and reactive currents.

Since electricity essentially sees the coils within a motor as an inductor, it affects multi-phase power in a way that's detrimental to its ability to transfer power

So capacitor Bank systems are designed to correct the issue so that the overall AC power quality isn't effected for downstream users.

Spectroscopy.

The surface temperature can be determined by the relative intensity of different spectral lines (the letter and number in the spectral class) or by the colour index (bluer is hotter).

If the distance is known independently, then given the apparent magnitude, distance, and surface temperature, the radius can be determined.

The width of the absorption lines in the star's spectrum (the Roman numberals in the spectral class) allows to infer the surface gravity of a star. And if you know the radius and the surface gravity you can calculate the mass.

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

I'm speaking size, not mass. I don't care about the brightness but only the diameter

I think you might be confusing size and mass.

A star (excluding systems with accretion) remains a relatively consistent mass for it's lifespan, but can increase in volume as it ages. This makes the older stars less dense and (for lack of a better term) more "wispy".

Stars with high masses will emit higher energy wavelengths closer to blue, while less dense red giants and supergiant's will emit more low engery wavelengths

I remember this news article of how a bird "re-evolved" itself. Here It might be similar to what OP said. Though it'll be better to find a scientific article than rely on clickbait news

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It is a question of timescales. Capacitors are typically used to “smooth out” power over timescales of nanoseconds to seconds (super capacitors can sometimes go up to minutes or hours). Batteries can smooth out power over timescales of minutes to years.

Batteries are also better at “clamping” to a certain voltage, while capacitor voltage is typically more variable.

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I never played Halo and don't know the game lore, so I can't really answer the question - I don't know what halo rings are supposed to be.

Lorentz forces, that is, forces due to the induced magnetic field of the outer cores geodynamo. I believe this is one of if not the leading mechanism proposed to explain this. Another mechanism would be angular momentum transport by thermal convection in the inner core. However, it is thought that the thermal conductivity within the inner core is too large and so the inner core is stably stratified (no convection and hence no radial transport of angular momentum).

Edit - I have been made aware of a rather amusing debacle in the reporting of a recent paper that is causing a lot of confusion. When I answered the question only the title was showing so my answer was very general to what we know of the inner core and its super rotation (although I did neglect the gravitational coupling between the departure of sphericity of the inner core and the mantle). See this threads top answer which is in context of the recent media hysteria!

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1. even if you start with the same animal, the random processes that make up evolution are vanishingly unlikely to produce the exact same end result twice when it's working with such an immense thing as the genetic code.
2. Other animals may well move in to occupy the niche that D occupied, if indeed the niche itself even exists any more (which it may well do again at some point).
3. C rarely continues to exist unchanged. There are some animals we think of as ancient but even those are rarely the exact same as they were 50 million years ago and even aside from that in the vast majority of cases C simply no longer exists in any form. I mean say humans went extinct next week. We look back to our last common ancestors with chimps: Gone. With gorillas? Gone. With other primates? Gone. I doubt there is a single extant animal (or any other kind of life) we can directly trace our lineage back to to give humans "another try" 5 billion years down the line. The same is probably true of most animals.

You don't count SN 1987A? From wikipedia, Ian Shelton "went outside to look with the naked eye, and saw that the bright light was indeed present".

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Yes, each supernova is a star dying. Scientists see some with telescope every year. Humans have seen a few with just their eyes, SN 1604: Kepler's Supernova is the latest one in 1604.

Most stars die without supernovae, but we don't see those.

Have we(humans) ever seen a star die?

It has happened many times. The crab has been evolved into several times throughout history. Rats and mice are not even closely related. Of course, it's not the same exact species each time but similar enough to be considered almost the same to most people.

Yes, in addition to what others have mentioned the other way to do it is to make a virus that can *only* replicate in cancer cells.

So the cancer cells aren't being directly targeted, but the mutant virus can't replicate in normal cells. Presumably when the virus enters non-cancerous cells it just gets quietly degraded during general protein and nucleic acid turn-over

This may sound weird at first. However, There is some overlap with the way some cancer cells and some viruses need to be able to disrupt the cell to replicate effectively.

Most cells in an adult are senescent or dividing very slowly, so all the machinery for DNA replication and spare bases are are at low levels.

Cancer cells divide by definition, and viruses tend to evolve to sort of force cells into dividing or dividing faster, so that they will then be able to replicate faster.

If these things get "turned on" when they shouldn't most cells will commit suicide (apoptosis) with the help of "checkpoint proteins" and other mechanisms. Cancer cells tend to have mutation in these checkpoints (which is why they don't commit suicide).

So one can imagine a scenario where you have a cancer with a known checkpoint mutation, and a virus that targets the same checkpoint protein (with one of the viruses numerous genes/proteins).

If you remove or mutate the gene in the virus that targets that checkpoint, the virus will only be able to replicate in cells that have a defective checkpoint.

I saw talks back in the late 90s where they had a few great results with inoperative head and neck tumors, but there were too many complications and deaths.

Information, like light, propagates at the speed of causality. The gravity of a black hole is enough to prevent anything from leaving the surface, even if an object could be engineered to survive, deployed, and reached within a human lifespan.