history - When did the Scutum constellation receive its current name?

While cleaning my desk, I found an out of date star map (puts the cleaning into perspective, huh?) where the Scutum constellation is still referred to as Scutum Sobiescianum). This is the original name Johannes Hevelius gave it in 1684

My map is (unfortunately) modern and comes from the 2nd half of the 20th century. It's a Polish one so it's not odd for it to still use the traditional name. The main illustration of the Scutum article in Polish Wikipedia happens to do so as well.

I know the name of the constellation has been changed but I can't find any information on who did it and when. I suppose it must have been the IAU (International Astronomical Union) but I have no idea regarding the time of the change.

When was the English name of the constellation officially changed and who did it?

How gravity works in a black hole?

Gravity works exactly the same around a black hole as it does everywhere else in the universe:

The mass of the black hole distorts spacetime, and then objects follow the shortest route in the curved spacetime. The only difference between the gravity of a black-hole and the gravity of Earth is that the Black hole has a much larger mass in a much smaller volume, so the gravitational field is much stronger.

The strength of gravity has several consequences I'll mention three:

First close to the black hole spacetime is so curved that light can't escape. Now all gravity bends light a bit, but you usually don't notice it. A black hole bends light a lot. The edge of the black hole is called an event horizon and it is the closest distance that light can go to a black hole and not fall in. Nothing can ever pass from within the event horizon.

Next there are tidal forces. All gravity can cause tides: the force of the earth gravity is a bit more on your feet than on your head. Usually you don't notice. However a solar mass black hole has such extreme tides that you would be pulled apart by the difference in force (this is the spaghettification you mention)

Finally, inside the black hole, space works like time. You can't change your direction in time (unless you have a Delorean) Inside a black hole you can't change direction in space.

But remember the only difference between the gravity around a black hole and the Earth is a matter of degree.

What was James Bradley's calculation to calculate the speed of light?

Despite many online sources crediting James Bradley with having calculated the speed of light to a 295.000 km/sec (britannica) or 301.000 km/sec (wikipedia), a small nuance ought to be added. Like Ole Romer before him in 1676, James Bradley calculated the speed of light relative to something else but both never provided a value in Earth-based units.

He wrote,

This therefore being 20’’,2, AC will be to AB that is the Velocity of Light to the Velocity of the Eye (which in
this Case may be supposed the same as the Velocity of the Earth's
annual Motion in its Orbit) as 10210 to One from whence it would follow
that Light moves or is propagated as far as from the Sun to the Earth
in 8’ 12’’.

(source)

The calculation to get to the ratio of 10210 is,

size of a radian (206265’’) / angle of aberration (20’’,2)

This ratio also holds for the speed of light to the speed of the earth. Not sure though exactly how britannica and wikipedia arrive at their respective values.

human biology - How fast do different organs turn over cells?

1) cell growth

You should look into chemotherapy and cancer medicine in general. Because chemo is mostly effective because it kills fast dividing cells, this has been worked out reasonably well. the 7-10 year number is not really correct, some cells are replaced a lot more slowly.

This is why hair often falls out in cancer treatment, because the follicle cells are growing quickly. Neurons divide very slowly - if at all - and often are never replaced. Fat cells are in between - probably replaced in the 7-10 year range. Heart cells are replaced albeit quite slowly - less than 1% per year, which implies that many cells are with you your entire lifetime.

2) atoms/molecules change

The cell itself is in a continuous state of flux, but different parts of the cell, like cells in the body, change at different rates. Some proteins which make up the cell matrix or the DNA in the nucleus are replaced very rarely (through repair or rearrangement of the chromosome for instance) and most of the chromosome DNA is with the cell for the entire life of the cell.

Most proteins are labelled for degradation and are recycled after a few hours of function. Metabolic compounds such as sugars or salt might drift in and out of the cell continuously, maybe turning over in an hour or so. Fats can be incorporated into the cell and last for years I think.

structural biology - Which factors besides the thermodynamic stability are important for the hairpin in intrinsic transcription termination?

Intrinsic termination (rho-independent) relies on a stable hairpin with a subsequent uridine repeat. The common explanation on how these sequences cause the termination of the transcription are based on the thermodynamic stability of the sequence. The GC-rich stable hairpin together with the destabilizing U-repeat supposedly destabilize the binding of the polymerase enough to cause it to disassociate from the template.

What I'm looking for are specific requirements on the termination sequences that are not based on thermodynamics.

• Are there any specific requirements on the hairpin sequence beyond a certain thermodynamic stability.


• Are there any loop variants that are known to reduce the termination efficiency?


• Does the shape of the hairpin, e.g. any kinks or bulges in it, have an influence on termination efficiency?

The typical requirements I read are 5-14bp and GC-rich, and I'd like to know if there are any more specific requirements, especially ones related to the structure and not the stability of the hairpin.

naming - What is the name of our Solar System?

To answer your question succinctly, the Solar System also goes by the names: The Copernican System, The Heliocentric System, and The Planetary System, in addition to the ones you have mentioned. There aren't too many other names, actually, so just stick to Solar System since it's the most widely accepted.

solar system - Does planets revolves around all the 88 constellations?

Planets does not go through all the constellations.

The path the Sun and the planets (approximately) follows is called the ecliptic. The constellation this line goes through is known as the Zodiac, but the current number is actually 13.

A star map, with the ecliptic drawn: