Answer:
The existence of a strong internal magnetic field allows probing of the interior through both long term changes of and short period fluctuations in that magnetic field. Venus, while Earth’s twin in many ways, lacks such a strong intrinsic magnetic field, but perhaps short period fluctuations can still be used to probe the electrical conductivity of the interior. Toward the end of the Venus Express mission, an aerobraking campaign took the spacecraft below the ionosphere into the very weakly electrically conducting atmosphere. As the spacecraft descended from 150 to 140 km altitude, the magnetic field became weaker on average and less noisy. Below 140 km, the median field strength became steady but the short period fluctuations continued to weaken. The weakness of the fluctuations indicates they might not be useful for electromagnetic sounding of the atmosphere from a high altitude platform such as a plane or balloon, but possibly could be attempted on a lander.
Introduction
The existence of a strong intrinsic magnetic field and the presence of time-varying fields can both be used to probe the electrical conductivity of a planetary crust1,2. Based on the Venus near-equatorial magnetic field surveyed down to 150 km altitude by the Pioneer Venus Orbiter (PVO), it is generally accepted that Venus has no significant global intrinsic field3,4. Although strong variable fields are present in the Venus ionosphere, these may be largely spatial variations, fossil fields impressed by slowly changing interplanetary magnetic fields “played back” at higher frequencies by the spacecraft’s rapid motion through the ionosphere. If so, then the fields at the surface of Venus resulting from the diffusion of the ionospheric magnetic field into the Venus atmosphere might be significantly weaker than in the ionosphere and much quieter5.
The Venus Express mission, designed to complement PVO, was inserted into an elliptical orbit with periapsis over north pole6,7. Initially, its periapsis was close to 78˚ latitude north and 250 km altitude. Later, the spacecraft periapsis moved to higher latitude over the pole and then to lower latitudes. Periapsis altitude was variable but typically remained above 160 km. A joint analysis of the Pioneer Venus and Venus Express measurements at low altitude within the ionosphere revealed that the magnetic field was horizontal on the dayside and expanded both into the wake at low altitudes and away from the wake at high altitudes8. During the last days of the Venus Express mission May – July 2014, an aerobraking campaign was performed. The changes of the spacecraft orbit allowed the periapsis to go as low as 129.7 km in altitude, which is well below the main peak ionosphere altitude of ~140 km9,10. Note that the lowest altitude measured by the PVO magnetometer was 150 km
Explanation:
Brian least po please
The answer to the question "us physicians..." is a. are well-trained in pain management.
This situation will produce a low birth rate, and likely decrease in individuals. It is a K-selected species.
<h3>K selected species</h3>
K-selected species are species in which the populations fluctuate in values near to the carrying capacity.
These species (K-selected) can be characterized by having long gestation periods, slow maturation and long life spans.
Occasional breeding is also a characteristic of K-selected species.
Learn more about K-selected species here:
brainly.com/question/9982086
<span>The answer is D. Example
of such a relationship is that of a tick and a cow. The tick is the
ectoparasite while the cow is the host.
The tick benefits by sucking blood from the cow while the cow is disadvantaged since it is losing some of its
blood and also the tick is a vector of disease</span>
Answer:
a) withheld information from test subjects about their condition
Explanation:
The Tuskegee syphilis study which was carried between 1932-1972 in the Macon County, Alabama on the African-Americans infected from syphilis.
The U.S. Public Health Service started the study promising the infected persons that they will receive the benefits from the studies like a healthy meal, proper antibiotic medication and other benefits.
But the U.S Public Health Service failed to provide the services mainly the medication in which antibiotic penicillin which could treat the disease was not provided to the patient. As a result of this, syphilis continued in their generations also and people and about 100 subjects died.
They were told that they had bad blood which cannot be treated and thus in 1972, this raised a question over this issue related to ethics as to why the penicillin was not provided as well why the person was kept away from the reality.
Thus, Option-A is the correct answer.
