Astrophysics

Mercury. An observer on the planet Mercury would see only one day every two Mercurian years. Venus is often cited as having a day longer than its year; but because of its retrograde motion (rotation opposite the direction of its orbital revolution) an observer on Venus (if they were able to see the Sun) would notice just under two days for each solar orbit or year - in this case the sun rising in the west and setting in the east.

Some sources say Neptune has 13 moons - others cite 14. The other gas giants all have more - Jupiter with 63, Saturn with 62, Uranus with 27 (depending on your source) so you could say all the above have at least 13.

The third motion of the Earth and other planets is known as axial tilt or obliquity. It refers to the angle at which the planet's axis is tilted in relation to its orbit around the Sun. This tilt is responsible for the changing seasons on Earth and plays a significant role in shaping the planet's climate and weather patterns.

Yes, the word "Venus" is capitalized because it is the name of a planet.

Winning the lottery is a game of chance, and there is no guaranteed strategy to win. In order to increase your chances, you can try buying more tickets or joining a lottery syndicate. However, ultimately, winning the lottery is a matter of luck.

The Earth is part of a larger system known as the Solar System, with the Sun roughly at the center, which the Earth orbits. The Solar System comprises the Sun, eight planets - one of which is Earth, and other objects. The solar system itself is also in orbit about the center of the galaxy (The Milky Way) which galaxy is part of a local grouping of galaxies, which is in turn part of a larger cluster of galaxies.

The reason for the slower movement of outer planets answers to the simple nature of the gravitational force, which varies with the inverse square of distance. For example, an object twice as distant would feel one quarter the gravitational pull. For a stable orbit, this would mean an outer planet would have to move more slowly. Meanwhile, the inner planets move more quickly, and Mercury, with an orbit closest to the sun, zips around it in only 88 days, compared to Naptune's 165 years.

Gravity will keep an object in the shape of a sphere, if the object is sufficiently large and massive, and if it doesn't rotate too fast. If it rotates quickly, it will be an ellipsoid - a flattened sphere. For example, Jupiter's diameter from pole to pole is approximately 10% less than its equatorial diameter, due to its quick rotation.

The planet with the highest eccentricity (in other words the most stretched or elongated ellipse) in our solar system is Mercury, with an eccentricity of about 0.21. (Pluto's is higher but is no longer considered a true planet).

By contrast, Venus is the most nearly a perfect circle with an eccentricity of about 0.007.

No one killed the planet Pluto. Pluto was reclassified as a "dwarf planet" by the International Astronomical Union (IAU) in 2006 due to its smaller size and different characteristics compared to the eight classical planets in our solar system. This decision was based on scientific understanding and classification criteria.

LOL Also watching Planet 51? Yeah, me too! :D

The corona is hotter than the photosphere because the sun's magnetic field carries energy upward from the surface and into the chromosphere and corona. The opposite effect is observed when the magnetic fields cause sunspots to form resulting in cooler surfaces.

Short Answer - who knows.

Long answer - Actually, if one accepts the notion of extraterrestrial beings coming from distant star systems or galaxies many many light years away, it would be presumed that having the technology to travel through space, they could be any colour - the skin colour native to their own home planet.

The 'Greys' (as per Close Encounters of the Third Kind) are so named for their skin tone and big eyes. The 'Black' or 'Dark' beings are so named for their dwarfish and muscular appearance and 'space-suit' colour.

Some movies even portray the 'Greys' as being 'suited' in a skin-like fabric.

The light that comes from the star. The light is spread out into its spectrum and the pattern of spectral lines allow the composition (and temperature) to be determined. The temp can also be found by looking at the black body curve for the star (also from spectrum), or, by looking at the color of the star (difference in intensity of the light through two different color filters typically B and V. The light that comes from the star. The light is spread out into its spectrum and the pattern of spectral lines allow the composition (and temperature) to be determined. The temp can also be found by looking at the black body curve for the star (also from spectrum), or, by looking at the color of the star (difference in intensity of the light through two different color filters typically B and V.

The most relevant quantity is the black hole's mass. Note that the black hole's diameter (the diameter of the event horizon, really) is directly proportional to its mass. The largest galactic black holes known seem to be around 20 billion solar masses. Check the Wikipedia "List of most massive black holes" for more details. Note that the mass of some of these black holes is not very well-known.

Possibly the European Union logo.

It usually means unity, solidarity and harmony.

X-rays have the shortest wavelength of those listed.

One btu will heat a pound of water about one degree Fahrenheit in one hour.

The relative mass of a proton measures around 1.0073, "relative" here being defined with respect to the atomic mass unit (or Dalton), a twelfth the mass of a carbon-12 atom in its ground state. So it's convenient to say a proton or neutron's relative mass is roughly 1 (the neutron being just barely heavier).

The relative mass of a substance is much more convenient to use than the actual mass since it is such a tiny fraction of the everyday units of mass.. the approximate number of protons it would take just to get one gram would be about six hundred thousand billion billion!

Christiaan Huygens, an astronomer, discovered Saturn's largest moon, Titan.

Among his other accomplishments:

* he correctly identified the rings of Saturn * mapped Mars * built the first practical pendulum clocks * formulated the wave theory of light

Guitar, bass, drums, and a shaker (... or some similar form of percussion instrument).

The guitar and bass have effects on them.

Specifically for a black hole the range of gravitational influence is calculated by the "Shwarzchild Radius" and surprisingly the radius is quite small for even the biggest blackhole, If a blackhole had the mass of the earth, then the Shwarzchild radius would only be a centimeter! Meaning you would have to come with in a centimeter of the blackhole to get sucked in.

Be careful. If you're already thinking about this, then be careful you don't get yourself and the boy into trouble. If you were to hold hands, or even kiss, that would be plenty far for kids of any age. Don't be in a hurry to lose something that you can never get back. I'm not suggesting that you let him kiss you either, but just be very careful.

There are several techniques to detect cosmic rays, using devices of various configurations (some of which you can even make at home). One of the oldest is the cloud chamber, where cosmic rays travel through a chamber containing vapor near its condensation point; as the cosmic ray (which is a high energy particle) collides with vapor molecules it cause them to breifly condense info visible cloud-like trails. A bubble chamber uses a similar method, where a liquid is kept near its boiling point, and a stream of bubbles can be made visible as the particle travels through the liquid causing a line of bubbles to form where the additional energy pushes the liquid briefly above the boiling point. Another technique uses parallel high voltage plates (spark chambers) in which a small channel in the gas between the plates can become ionized in the path of the cosmic rays, causing a spark to travel between the plates making the path visible. Geiger counters, and scintillators use other techniques to detect cosmic rays.