What are the atmospheric conditions of mercury?
Mercury has a very tenuous and highly variable atmosphere (surface-bound exosphere) containing hydrogen, helium, oxygen, sodium, calcium, potassium and water vapor, with a combined pressure level of about 10−14 bar (1 nPa). The exospheric species originate either from the Solar wind or from the planetary crust.
Why doesn't Mercury have an atmosphere?
Why doesn't Mercury have an atmosphere? There are two main reasons. First, Mercury is small and doesn't have much gravity so it's hard to hold onto an atmosphere. Second, Mercury is close to the Sun so any atmosphere gets blasted away by stuff being blown off the Sun. Trivia Because Mercury has no atmosphere, it can't hold onto its heat very well.
What is Mercury's atmosphere like?
Mercury's Atmosphere
- Atmospheric components. Mercury is the smallest and least massive of the eight planets. ...
- A tail like a comet. While some of the particles kicked up by the sun fall back onto the planet, some of it drifts away, forming a comet-like tail behind ...
- Climate and weather. With virtually no atmosphere, Mercury feels very little in terms of traditional weather. ...
What are the atmospheric features of mercury?
Surface Features of Mercury
- Impact Basins. This is one of the largest impact basins in the solar system and the largest feature on Mercury. ...
- Scarps. A Shrinking Planet? ...
- Volcanism. Between the heavily cratered regions of Mercury's surface lie large expanses of smooth plains. ...
- Water Ice. ...
- Ridges and Troughs. ...
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What is the atmosphere of mercury?
Mercury has a very tenuous and highly variable atmosphere (surface-bound exosphere) containing hydrogen, helium, oxygen, sodium, calcium, potassium and water vapor, with a combined pressure level of about 10 −14 bar (1 nPa ). The exospheric species originate either from the Solar wind or from the planetary crust.
What is the temperature of mercury?
The temperature of Mercury's exosphere depends on species as well as geographical location. For exospheric atomic hydrogen, the temperature appears to be about 420 K , a value obtained by both Mariner 10 and MESSENGER. The temperature for sodium is much higher, reaching 750–1,500 K on the equator and 1,500–3,500 K at the poles.
What is the fourth species of mercury?
The fourth species detected in Mercury's exosphere was sodium (Na). It was discovered in 1985 by Drew Potter and Tom Morgan, who observed its Fraunhofer emission lines at 589 and 589.6 nm. The average column density of this element is about 1 × 10 11 cm −2.
What are the ions in mercury?
In 2008 the MESSENGER probe's Fast Imaging Plasma Spectrometer (FIPS) discovered several molecular and different ions in the vicinity of Mercury, including H 2 O + (ionized water vapor) and H 2 S + (ionized hydrogen sulfide ). Their abundances relative to sodium are about 0.2 and 0.7, respectively. Other ions such as H 3 O + ( hydronium ), OH ( hydroxyl ), O 2+ and Si + are present as well. During its 2009 flyby, the Ultraviolet and Visible Spectrometer (UVVS) channel of the Mercury Atmospheric and Surface Composition Spectrometer (MASCS) on board the MESSENGER spacecraft first revealed the presence of magnesium in the Mercurian exosphere. The near-surface abundance of this newly detected constituent is roughly comparable to that of sodium.
What is the name of the spectrometer that detects magnesium in the atmosphere?
During its 2009 flyby, the Ultraviolet and Visible Spectrometer (UVVS) channel of the Mercury Atmospheric and Surface Composition Spectrometer (MASCS) on board the MESSENGER spacecraft first revealed the presence of magnesium in the Mercurian exosphere.
What element is concentrated near the equator?
In 1998 another element, calcium (Ca), was detected with column density three orders of magnitude below that of sodium. Observations by the MESSENGER probe in 2009 showed that calcium is concentrated mainly near the equator—opposite to what is observed for sodium and potassium.
When was the Mercurian atmosphere discovered?
The existence of a Mercurian atmosphere had been contentious before 1974, although by that time a consensus had formed that Mercury, like the Moon, lacked any substantial atmosphere. This conclusion was confirmed in 1974 when the unmanned Mariner 10 spaceprobe discovered only a tenuous exosphere. Later, in 2008, improved measurements were obtained by the MESSENGER spacecraft, which discovered magnesium in the Mercurian exosphere.
How big is Mercury?
Size and Distance. With a radius of 1,516 miles (2,440 kilometers), Mercury is a little more than 1/3 the width of Earth. If Earth were the size of a nickel, Mercury would be about as big as a blueberry. From an average distance of 36 million miles (58 million kilometers), Mercury is 0.4 astronomical units away from the Sun.
What is the temperature of Mercury?
Without an atmosphere to retain that heat at night, temperatures can dip as low as -290°F (-180°C). Introduction. The smallest planet in our solar system and nearest to the Sun, Mercury is only slightly larger than Earth's Moon. From the surface of Mercury, the Sun would appear more than three times as large as it does when viewed from Earth, ...
Why do the rays of mercury look brighter?
Fine particles of crushed rock are more reflective than large pieces, so the rays look brighter. The space environment—dust impacts and solar-wind particles—causes the rays to darken with time. Temperatures on the surface of Mercury are extreme, both hot and cold.
What is the exosphere of Mercury?
Mercury's exosphere is composed mostly of oxygen, sodium, hydrogen, helium and potassium. Magnetosphere.
How far is Mercury from the Sun?
From an average distance of 36 million miles (58 million kilometers), Mercury is 0.4 astronomical units away from the Sun. One astronomical unit (abbreviated as AU), is the distance from the Sun to Earth. From this distance, it takes sunlight 3.2 minutes to travel from the Sun to Mercury.
What are the bright streaks on Mercury called?
Most of Mercury's surface would appear greyish-brown to the human eye. The bright streaks are called "crater rays.". They are formed when an asteroid or comet strikes the surface.
How fast does Mercury travel?
It speeds around the Sun every 88 days, traveling through space at nearly 29 miles (47 kilometers) per second , faster than any other planet.
What is the composition of Mercury?
Mercury atmospheric composition: Oxygen 42%. Sodium 29%. Hydrogen 22%. Helium 6%. Potassium 0.5%.
Where does the Mercurian atmosphere come from?
It is thought that it originates from peroxides and perchlorates in the soil or that it condenses and evaporates seasonally from clathrates. Despite how small the Mercurian atmosphere is, it has been broken down into four components by NASA scientists. Those components are the lower, middle, upper, and exosphere.
Why did Mercury's atmosphere dissipate?
This was because of Mercury’s lower gravity, and because it’s so close to the Sun and receives the constant buffeting from its solar wind. Its current atmosphere is almost negligible.
How far does the exosphere start?
The exosphere starts at about 200 km and has no clear end. It just tapers off into space. While that may sound like a lot of atmosphere separating the planet from the solar wind and ultraviolet radiation, it is not. Helping Mercury hold on to its atmosphere is its magnetic field.
What is the middle atmosphere?
This airborne dust gives the planet its ruddy brown appearance. The middle atmosphere contains a jetstream like Earth’s. The upper atmosphere is heated by the solar wind and the temperatures are much higher than at the surface. The higher temperatures separate the gases.
What are the components of the atmosphere?
Those components are the lower, middle, upper, and exosphere. The lower atmosphere is a warm region (around 210 K). It is warmed by the combination of airborne dust (1.5 micrometers in diameter) and heat radiated from the surface. This airborne dust gives the planet its ruddy brown appearance.
What episode of Astronomy Cast is about atmospheres?
We have also recorded an entire episode of Astronomy Cast all about atmospheres. Listen here, Episode 151: Atmospheres.
What are the elements in the atmosphere of Mercury?
The elements contained in Mercury’s exosphere are helium, hydrogen, oxygen, sodium, calcium, potassium and water vapor. The comet-like tail that is seen on the end of the planet is created by atmospheric gasses that are pushed by solar light. Sodium is the primary element located in its tail. Mercury’s tail extends very far from the planet. Other elements in its tail include traces of calcium and magnesium but these do not extend as far as the sodium tail do.
Where do the elements in the exosphere come from?
Most of the particles in the exosphere escape into space. This implies that the elements in the exosphere are constantly being supplied by its constituents. The source of the hydrogen and helium in the exosphere is the Solar Wind. Other atoms and molecules come from the crust of Mercury itself. The main supply of the elements found in Mercury’s exosphere are from vaporized surface material caused by meteors hitting its surface, energetic charged particles that are emitted by the Solar Wind and the desorption of atoms of alkali metals.
Is there an atmosphere on Mercury?
Before 1974, the existence of an atmosphere in Mercury was a topic that produced heated debates. Because Mercury is too close to the Sun, it was very hard to study. It wasn’t until the Mariner 10 spacecraft discovered the exosphere of Mercury’s atmosphere. The data gathered by the Mariner 10 spacecraft confirmed that only an exosphere existed on Mercury and is similar to the Moon in having no atmosphere. On 2008 the Messenger spacecraft found magnesium in its exosphere.
What is the thin atmosphere of Mercury?
Compared to Earth's atmosphere, that of Mercury is thin enough to be almost negligible; scientists weren't sure it was there until they received data from the Mariner 10 spacecraft, which conducted multiple flybys of the planet in 1974 and 1975. After analyzing data from the Messenger spacecraft, which launched in 2004 and sends detailed atmospheric readings from Mercury orbit, scientists now know more about the thin atmosphere's composition. It is 95.3 percent carbon dioxide, 2.7 percent nitrogen, 1.6 percent argon and about 0.2 percent oxygen, with trace amounts of carbon monoxide, water vapor and nitric oxide, as well as sulfur, iron, calcium, magnesium, sodium and organic compounds.
Why does Mercury have an atmosphere?
Because Mercury is so small and so close to the sun, it has a hard time attracting an atmosphere, but it does have one. Its atmosphere is so thin, though, astronomers usually refer to it as an exosphere.
How is Mercury different from Earth?
Mercury's diameter is a third as large as that of the Earth, but in terms of volume, it is 18 times smaller. The planet is dense, though, and gravitational attraction on its surface is about one-third of what it is on Earth. Although scientists used to believe it had no magnetic field, they now know it has one, but it is only about 1 percent as strong as Earth's. Because Mercury has an iron core that accounts for 42 percent of its volume, the weakness of its magnetic field is puzzling, but the probable cause is the same one that prevents the planet from having a thick atmosphere -- the solar wind.
Why is Mercury's magnetic field weak?
Because Mercury has an iron core that accounts for 42 percent of its volume, the weakness of its magnetic field is puzzling, but the probable cause is the same one that prevents the planet from having a thick atmosphere -- the solar wind.
What is the composition of the thin atmosphere?
It is 95.3 percent carbon dioxide, 2.7 percent nitrogen, 1.6 percent argon and about 0.2 percent oxygen, with trace amounts of carbon monoxide, ...
Is Mercury's atmosphere static?
Data from Messenger also revealed that Mercury's atmosphere isn't static. It changes from pole to pole, and its composition varies according to the planet's distance from the sun. Mercury has an eccentric orbit.
Why is the atmosphere of Mercury unstable?
As the atmosphere’s materials are being made, they are also being taken away at the uppermost layers due to solar winds. The composition of the atmosphere can also change as you move across the planet.
Why is Mercury's atmosphere empty?
The problem Mercury faces is that its atmosphere is in danger of being blown away by the powerful solar winds coming from the Sun. Scientists find that the molecules in the atmosphere are constantly being restored and replaced, so the atmosphere is never quite empty.
What is the magnetic field of Mercury?
Scientists suggest that dust and rocks kicked into the air by wind or meteorites may be giving the atmosphere its molecules, or solar winds could be kicking up dust and gas. Mercury also has a magnetic field, and has two poles.
What is the difference between Mercury and Earth?
Mercury has a low gravity and receives large gusts of solar winds from the nearby Sun. Earth’s atmosphere contains nitrogen, oxygen, argon, carbon dioxide, and a few other molecules . Mercury, on the other hand, contains hydrogen, helium, oxygen, sodium, calcium, potassium, and water.
What is the thinnest atmosphere in the solar system?
The atmosphere is calculated as the thinnest atmosphere of all the planets in our Solar System. Scientists are still exploring and learning about Mercury’s atmosphere, but they have discovered a few things. Mercury has a low gravity and receives large gusts of solar winds from the nearby Sun.
How does the magnetic field help the atmosphere?
While the magnetic field is nearly 150 times weaker than our own on Earth, this magnetic fields helps hold its atmosphere in place by reducing the impact of the solar winds. Gravity is the other force that helps hold the atmosphere’s gasses in place.
Does Mercury have an atmosphere?
While Mercury does have an atmosphere, it is very thin and constantly trying to exist around Mercury.
Overview
Mercury, being the closest to the Sun, with a weak magnetic field and the smallest mass of the recognized terrestrial planets, has a very tenuous and highly variable atmosphere (surface-bound exosphere) containing hydrogen, helium, oxygen, sodium, calcium, potassium and water vapor, with a combined pressure level of about 10 bar (1 nPa). The exospheric species originate either f…
Composition
The Mercurian exosphere consists of a variety of species originating either from the Solar wind or from the planetary crust. The first constituents discovered were atomic hydrogen (H), helium (He) and atomic oxygen (O), which were observed by the ultraviolet radiation photometer of the Mariner 10 spaceprobe in 1974. The near-surface concentrations of these elements were estimated to vary from 2…
Properties
Mariner 10's ultraviolet observations have established an upper bound on the exospheric surface density at about 10 particles per cubic centimeter. This corresponds to a surface pressure of less than 10 bar (1 nPa).
The temperature of Mercury's exosphere depends on species as well as geographical location. For exospheric atomic hydrogen, the temperature appe…
Observation difficulties
Mercury is the least explored planet of the inner Solar System due to the many difficulties of observation. The position of Mercury as seen from Earth is always very close to the Sun, which causes challenges when trying to observe it. The Hubble Space Telescope and other Earth-based space imaging systems have highly sensitive sensors so they can observe deep space objects. They must not be directed toward the Sun, lest its powerful radiation destroy the sensors.
See also
• Orders of magnitude (pressure)
• Magnetosphere of Mercury