To determine the lifetime of a 1.43MSun star, we use the formula for stellar lifetimes. Sun 2.5 tsun tstar M. star Using the given mass and multiplying by the expected lifetime of the Sun (11 x 10° years), we can calculate the following. (Round your answer to at least three significant figures.) tstar = years

Kepler-444 is one of many stars with terrestrial planets that is over 10 billion a) What do you think the spectral type of Kepler-444 might be? b) How do stars of this spectral type end their lives? c) If evolution followed a similar course on a habitable pranet around a star similar to Kepler-444, it would be 5 billion years more advanced than we are. Let’s try to project our future and see what happens. In particular, suppose our civilization gets motivated enough to colonize another planet. Kepler indicates that most stars have potentially habitable (and colonizable) planets, so roughly how far away is the typical “nearest" planet? d) The New Horizons probe on its way to Pluto took 9 years to travel 30 AU. If we could send colony ships with the same average speed, roughly how long would it take to reach the typical nearest planet? уears old.

Tutorial A radio broadcast left Earth in 1923. How far in light years has it traveled? If there is, on average, 1 star system per 400 cubic light years, how many star systems has this broadcast reached? Assume that the fraction of these star systems that have planets is 0.50 and that, in a given planetary system, the average number of planets that have orbited in the habitable zone for 4 billion years is 0.40. How many possible planets with life could have heard this signal? Part 1 of 3 To figure out how many light years a signal has traveled we need to know how long since the signal left Earth. If the signal left in 1923, distance in light years = time since broadcast left Earth. d = tnow - broadcast d = 97 97 light years Part 2 of 3 Since the radio signal travels in all directions, it expanded as a sphere with a radius equal to the distance it has traveled so far. To determine the number of star systems this signal has reached, we need to determine the volume of that sphere. V, = Vb…

Tutorial A radio broadcast left Earth in 1925. How far in light years has it traveled? If there is, on average, 1 star system per 400 cubic light years, how many star systems has this broadcast reached? Assume that the fraction of these star systems that have planets is 0.30 and that, in a given planetary system, the average number of planets that have orbited in the habitable zone for 4 billion years is 0.85. How many possible planets with life could have heard this signal? Part 1 of 3 To figure out how many light years a signal has traveled we need to know how long since the signal left Earth. If the signal left in 1925, distance in light years = time since broadcast left Earth. d = tnow - tbroadcast d = light years Submit Skip (you cannot come back)

As a consequence of conservation of ............., the 2nd Law of Planetary Motion also implies that a planet will move ............ when farther away from its host star.

The Sun is moving at 220 ??/? around the Galactic Center at a more-or-less constant distance of 8.5 ???. To appreciate how remarkable this is, consider the following questions: a) How massive would the Sun have to be for the Earth to have an orbital velocity of 220 km/s at 1 AU? b) How fast would the Earth move if it was in orbit around the Sun at a distance of 8.5 kpc? Of course, you may ignore the effects of all other stars in this calculation.

Suppose that Earth grew to its present size in 11 million years from particles averaging 80 g each. On average, how many particles did Rarth capture per second? (Notes: 1 yr = 3.2 x 10^7 s. See appendix A to find Earths mass.)  _______ particles per second

what is the scientific concept used in the test? how old is the rock in years? scientist agree that the age of the universe is about 4 billion years old, does the age of the rock referred in the problem support that? why?

Please help me with this question. A=.2

In a globular cluster, astronomers (someday) discover a star with the same mass as our Sun, but consisting entirely of hydrogen and helium. Is this star a good place to point our SETI antennas and search for radio signals from an advanced civilization? Group of answer choices   No, because such a star (and any planets around it) would not have the heavier elements (carbon, nitrogen, oxygen, etc.) that we believe are necessary to start life as we know it.   Yes, because globular clusters are among the closest star clusters to us, so that they would be easy to search for radio signals.   Yes, because we have already found radio signals from another civilization living near a star in a globular cluster.   No, because such a star would most likely not have a stable (main-sequence) stage that is long enough for a technological civilization to develop.   Yes, because such a star is probably old and a technological civilization will have had a long time to evolve and develop there.