We can determine orbital period and distance and orbital eccentricity with any method, mass with astrometric or doppler methods, size with the transit method, and density when the 2 methods are used together, and a little bit about a planet’s atmospheric composition and temperature with transits.
Which planetary properties we can measure using transit method?
ANSWER: In the transit method, the fraction of light absorbed is the ratio of the planet’s area to the star’s area, so we can find the physical size of the planet . If we also measure its mass via radial velocity, we can calculate its density.
Which planetary properties we can measure using astrometric method quizlet?
the astrometric technique watches for tiny movements of a star against the background of other stars. It’s best for detecting massive planets that orbit far from their stars , even though distant planets take longer to orbit. Current technology limits its use to very rare cases. It works best for nearby stars.
What can the astrometric method measure?
Astrometry is the method that detects the motion of a star by making precise measurements of its position on the sky . This technique can also be used to identify planets around a star by measuring tiny changes in the star’s position as it wobbles around the center of mass of the planetary system.
Which of the following characteristics of a planet can the transit method detect?
For planets that do transit, astronomers can get valuable information about the planet’s atmosphere, surface temperatures and size . For most sun-like stars, an orbiting planet even as large as a brown dwarf will only cause an observed reduction in brightness of the star of a few percent or less during a transit.
Why the transit method is considered so valuable?
Astronomers can glean some very important information about planets detected using this method. As the planetary transit is periodical in nature astronomers can determine the planets orbital period . ... An additional bonus of the transit method is that it can hint at the planets atmospheric make up, if it has one.
What is a disadvantage of the transit method?
Disadvantages. The main difficulty with the transit-photometry method is that in order for the photometric effect to be measured, a transit must occur . Not all planets orbiting other stars transit their stars as seen from Earth; a distant planet must pass directly between its star and Earth.
What is an Exosolar system?
An extrasolar planet (aka. exoplanet) is a planet that orbits a star (i.e. is part of a solar system) other than our own . Our Solar System is only one among billions and many of them most likely have their own system of planets.
Why are these orbits surprising quizlet?
This was surprising since our planet formation model suggests that planets should have nearly circular orbits and that jovian planets, which require ice to form, should form nearer to the star in the solar system. ... Some extrasolar planets are likely to be made mostly of water. The statement doesn’t make sense.
What is planetary migration quizlet?
What is planetary migration, and how may it account for the surprising orbits of many extrasolar planets? Migration means the planet gradually moves closer to its parent star . Many extrasolar planets are much closer to their stars than we had expected.
Why is it so difficult to see exoplanets directly in an image?
The major problem astronomers face in trying to directly image exoplanets is that the stars they orbit are millions of times brighter than their planets . Any light reflected off of the planet or heat radiation from the planet itself is drowned out by the massive amounts of radiation coming from its host star.
What are the strengths and limitations of the Doppler method?
What are the strengths and limitations of the Doppler method? The Doppler technique has the main advantage of being able to detect planets in a wide range of orbits —as long as the orbit is not face-on. Its disadvantage is that it can yield only the planet’s mass and orbital properties.
Do stars wobble?
The slightly off-center barycenter is what makes the star appear to wobble back and forth . Planets around other stars—called exoplanets—are very hard to see directly. They are hidden by the bright glare of the stars they orbit. Detecting a star’s wobble is one way to find out if there are planets orbiting it.
What is transit associated with?
In astronomy, a transit (or astronomical transit) is a phenomenon when a celestial body passes directly between a larger body and the observer . ... The word “transit” refers to cases where the nearer object appears smaller than the more distant object.
What can we learn from transits?
We can also learn about an exoplanet’s atmosphere during a transit . As it transits, some light will go through its atmosphere and that light can be analyzed to determine what different atmospheric elements influenced its particular dispersion. Atmospheric composition is important to determining habitability.
What is the transit method used for?
The transit method is a photometric method that aims to indirectly detect the presence of one or more exoplanets in orbit around a star . In 1999, the method was used to confirm the existence of HD209458b, a planet that had been discovered almost at the same time by the radial velocity method.
