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How is the historical moon landing changed our scientific understanding and how this event added to or changed our understanding of science.
To convert one kilogram of hydrogen (1H) into helium (4He), you must start with 1.5 kg of hydrogen. Please explain why, and explain what happens to the other 0.5kg.
What is the phase of the Moon if it rises at 1. Midnight? 2. Sunrise? 3. Halfway between sunset and midnight? 4. Halfway between noon and sunset? Please explain.
The attached image of the Earth was made by the Galileo spacecraft while en route to Jupiter. South America is at the center of the image and Antarctica is at the bottom of the image. 1. In which month of the year was this image made? Please explain. 2. When this image was made, was the Earth relatively close to the S ...continues
When observing the Earth's orbit, how does it relate to the galaxy's plane?
Imagine that a civilization in another planetary system is sending a radio signal toward Earth. As our planet moves in its orbit around the Sun, the wavelength of the signal we receive will change due to the Doppler effect. This give SETI scientists a way to distinguish stray signals of terrestrial origin (which will not show ...continues
In the spectrum of the galaxy NGC4839, the K line of a singly ionized calcium has a wavelength 403.2 nm. (a) What is the redshift of this galaxy? (b). Determine the distance to this galaxy using the Hubble law with H0 = 73km/s/Mpc.
(a) Calculate the Schwarzschild radius of a supermassive black hole of mass 3.7 x 10^6 M., the estimated mass of the black hole at the galactic center. Give your answer in both kilometers and astronomical units. (b) What is the angular diameter of such a black hole as seen at a distance of 8 kpc, the distance from the Ear ...continues
The orbital period of the binary system containing A0620-00 is 0.32 day, and Doppler shift measurements reveal that the radial velocity of the X-ray source peaks at 457 km/s (about 1 million miles per hour). a) Assuming that the orbit of the X-ray source is a circle, find the radius of its orbit in kilometers. (This is act ...continues
Suppose that the brightness of a star becoming a supernova increases by 20 magnitudes. Show that this corresponds to an increase of 10^8 in luminosity.
The total luminosity at all wavelengths of the magnetar burst observed on December 27, 2006, was approximately 10^14 L. At what distance from the magnetar would the brightness of the burst have been equal to the brightness of the Sun as seen on Earth? Can you give the answer in AU and in parsecs.
At one stage during its birth, the protosun had a luminosity of 1000L and a surface temperature of about 1000K. What was its radius at this time? Please give the answer in three different ways: As a multiple of the sun's present day radius, In kilometers, and In astronomical units.
How much dimmer does the sun appear from Neptune than from Earth? The average distance between a planet and the sun equals the semimajor axis of the planet's orbit. I think you need to calculate a ratio, but I'm not sure.
Please answer in detail. Thanks!! A force of 300 pounds compresses a 10-inch string to a length of 4 inches. 1) Calculate the work done in compressing the spring an additional 2 inches. 2) Calculate the work done in compressing the spring a total of 4 inches (from its natural length).
What is the makeup of the solar nebula and what did it have to do with the formation of the planets?
How did Galileo's observations show that the Earth center theory (Ptolemaic) was wrong?
Determine if the following statement is true or false. If false, explain why and give an example that shows it is false. See attached file for full problem description.
Why do you think it was so difficult for people to accept the heliocentric model in the 1600s? And what do you think was the impact of this model, once it was accepted?
Why is it more difficult to notice the westward motions of the stars that are high in the sky than those that are near the horizon?
Explain why Cephid variable stars are so useful for determining the distances of galaxies.
In 2 paragraph please explain the method by which most planets have been discovered around other stars.
Explain in your own words why the observation of a full set of phases for Venus backs the Copernican system.