Understand the planets
It’s often hard to fully grasp just how big the planets in the solar system are. 1.3 million Earths could fit in the Sun, but that is hard to picture. A good way to help with this problem is drawing the planets to scale. This dataset has the Sun as the background and then has a picture of the solar system drawn to scale. The Sun is also to scale with the rest of the planets.
By far, Jupiter is the largest planet with Saturn the second largest, but they are certainly no where close to being as big as the Sun, which has a radius of 432,000 miles (695,000 km). Now that Pluto is no longer classified as a planet, Mercury, the closest planet to the Sun, is the smallest planet with a radius of 1516 miles (2440 km).
The second planet in the solar system, Venus, is the third smallest planet with a radius of 3761 miles (6052 km).
Earth, of course, is the third closest planet to the Sun and the fourth smallest with a radius of 3963 miles (6378 km). Just past Earth is Mars, the fourth planet in the solar system. Mars is the second smallest planet with a radius of 2111 miles (3397 km). The first four planets are called terrestrial planets because they are made mainly of rock and have thin wispy atmospheres.
The outer planets are called gas giants because they are large and consist mainly of hydrogen and helium. The gas giants also typically have a large number of moons, while the terrestrial planets have limited moons. The first gas giant, Jupiter, is certainly a giant. The radius of Jupiter is 44,423 miles (71492 km). More than 1300 Earth’s could fit inside Jupiter.
The next planet past Jupiter is Saturn, the second largest planet. The radius of Saturn is 37,449 miles (60268 km). The rings of Saturn would be the width of a credit card and would extend much further than the picture shows. The edge of the brightest rings extends 75,900 miles (122,200 km) from Saturn and the faintest rings extend out 300,000 miles (483,000 km) from Saturn. The seventh planet from the sun is Uranus.
Uranus ranks as the third largest planet with a radius of 15882 miles (25,559 km).
Now considered the eighth and final planet in the solar system is Neptune, the fourth largest planet with a radius of 15,389 miles (24,766 km). Uranus and Neptune are very close in size. The final object in the picture is Pluto, which is now classified as a dwarf planet. Pluto only has a radius of 715 miles (1150 km).
It was demoted from planet to dwarf planet in 2006 when new guidelines were created to classify planets and Pluto didn’t meet all of the qualifications.
Over the past 60 years, humans have begun to explore our solar system in earnest. From the first launches in the late 1950s until today, we’ve sent probes, orbiters, landers and even rovers (like NASA’s Perseverance Rover that touched down on Mars in February 2021) to every planet in our solar system.
But can you name all eight of those planets? (Yes, there’s only eight – not nine. Pluto got “demoted” in 2006.) And can you put them in the correct order?
It is the second planet from the Sun. It is named after the Roman goddess of love and beauty. As the brightest natural object in Earth’s night sky after the Moon, Venus can cast shadows and can be visible to the naked eye in broad daylight.
Venus lies within Earth’s orbit, and so never appears to venture far from the Sun, either setting in the west just after dusk or rising in the east a little while before dawn. Venus orbits the Sun every 224.7 Earth days. It has a synodic day length of 117 Earth days and a sidereal rotation period of 243 Earth days.
As a consequence, it takes longer to rotate about its axis than any other planet in the Solar System, and does so in the opposite direction to all but Uranus. This means the Sun rises in the west and sets in the east. Venus does not have any moons, a distinction it shares only with Mercury among the planets in the Solar System.
what is the 2nd planet from the sun
Venus is a terrestrial planet and is sometimes called Earth’s “sister planet” because of their similar size, mass, proximity to the Sun, and bulk composition. It is radically different from Earth in other respects. It has the densest atmosphere of the four terrestrial planets, consisting of more than 96% carbon dioxide.
The atmospheric pressure at the planet’s surface is about 92 times the sea level pressure of Earth, or roughly the pressure at 900 m (3,000 ft) underwater on Earth. Even though Mercury is closer to the Sun, Venus has the hottest surface of any planet in the Solar System, with a mean temperature of 737 K (464 °C; 867 °F).
Venus is shrouded by an opaque layer of highly reflective clouds of sulfuric acid, preventing its surface from being seen from space in light. It may have had water oceans in the past, but these would have vaporized as the temperature rose under a runaway greenhouse effect.
water and hydrogen
The water has probably photodissociated, and the free hydrogen has been swept into interplanetary space by the solar wind because of the lack of a planetary magnetic field.As one of the brightest objects in the sky, Venus has been a major fixture in human culture for as long as records have existed.
It has been made sacred to gods of many cultures, and has been a prime inspiration for writers and poets as the “morning star” and “evening star”. Venus was the first planet to have its motions plotted across the sky, as early as the second millennium BC.
Viewed through a telescope, Venus presents a brilliant yellow-white, essentially featureless face to the observer. Its obscured appearance results from the surface of the planet being hidden from sight by a continuous and permanent cover of clouds. Features in the clouds are difficult to see in visible light.
When observed at ultraviolet wavelengths, the clouds exhibit distinctive dark markings, with complex swirling patterns near the equator and global-scale bright and dark bands that are V-shaped and open toward the west. Because of the all-enveloping clouds, little was known about Venus’s surface, atmosphere, and evolution before the early 1960s, when the first radar observations were undertaken and spacecraft made the first flybys of the planet.
The rotation of Venus on its axis is unusual in both its direction and its speed. The Sun and most of the planets in the solar system rotate in a counterclockwise direction when viewed from above their north poles; this direction is called direct, or prograde. Venus, however, rotates in the opposite, or retrograde, direction.
Were it not for the planet’s clouds, an observer on Venus’s surface would see the Sun rise in the west and set in the east. Venus spins very slowly, taking about 243 Earth days to complete one rotation with respect to the stars—the length of its sidereal day.
Venus rotates in harmony with the earth
Venus’s spin and orbital periods are very nearly synchronized with Earth’s orbit such that, when the two planets are at their closest, Venus presents almost the same face toward Earth. The reasons for this are complex and have to do with the gravitational interactions of Venus, Earth, and the Sun, as well as the effects of Venus’s massive rotating atmosphere.
Because Venus’s spin axis is tilted only about 3° toward the plane of its orbit, the planet does not have appreciable seasons. Also, Venus’s rotational period slowed by 6.5 minutes between two sets of measurements taken in 1990–92 and 2006–08.
Astronomers as yet have no satisfactory explanation for Venus’s peculiar rotational characteristics. The idea cited most often is that, when Venus was forming from the accretion of planetary building blocks (planetesimals). One of the largest of these bodies collided with the proto-Venus in such a way as to tip it over. And possibly slow its spin as well.
Radius of Venus
Venus’s mean radius is 6,051.8 km (3,760.4 miles), or about 95 percent of Earth’s at the Equator, while its mass is 4.87 × 1024 kg, or 81.5 percent that of Earth. The similarities to Earth in size and mass produce a similarity in density—5.24 grams per cubic centimetre for Venus, compared with 5.52 for Earth.
They also result in a comparable surface gravity—humans standing on Venus would possess nearly 90 percent of their weight on Earth. Venus is more nearly spherical than most planets. A planet’s rotation generally causes a bulging at the equator. And a slight flattening at the poles. But Venus’s very slow spin allows it to maintain its highly spherical shape.
The atmosphere of Venus
Venus has the most massive atmosphere of the terrestrial planets, which include Mercury, Earth, and Mars. Its gaseous envelope is composed of more than 96 percent carbon dioxide and 3.5 percent molecular nitrogen. Trace amounts of other gases are present, including carbon monoxide, sulfur dioxide, water vapour, argon, and helium.
The atmospheric pressure at the planet’s surface varies with surface elevation. At the elevation of the planet’s mean radius it is about 95 bars, or 95 times the atmospheric pressure at Earth’s surface. This is the same pressure found at a depth of about 1 km (0.6 mile) in Earth’s oceans.
Its proximity to Earth has made Venus a prime target for early interplanetary exploration. It was the first planet beyond Earth visited by a spacecraft (Venera 1 in 1961), and the first to be successfully landed on (by Venera 7 in 1970).
Venusian thick clouds render observation of its surface impossible in visible spectrum. And the first detailed maps did not emerge until the arrival of the Magellan orbiter in 1991. Plans have been proposed for rovers or more complex missions, but they are hindered by Venus’s hostile surface conditions. The possibility of life on Venus has long been a topic of speculation. And in recent years it has received active research.
WHAT IS VENUS LIKE?
Venus and Earth are often called twins because they are similar in size, mass, density, composition and gravity. Venus is actually only a little bit smaller than our home planet, with a mass about 80% of Earth’s.
The interior of Venus is made of a metallic iron core that’s roughly 2,400 miles (6,000 km) wide. Venus’ molten rocky mantle is roughly 1,200 miles (3,000 km) thick. Its crust is mostly basalt. And it is estimated to be 6 to 12 miles (10 to 20 km) thick, on average.
It is the hottest planet in the solar system. Although Venus is not the planet closest to the sun, its dense atmosphere traps heat in a runaway version of the greenhouse effect that warms Earth. As a result, temperatures on Venus reach 880 degrees Fahrenheit (471 degrees Celsius), which is more than hot enough to melt lead. Spacecraft have survived only a few hours after landing on the planet before being destroyed.
Very heavy atmosphere
With scorching temperatures, Venus also has a hellish atmosphere, that consists mainly of carbon dioxide with clouds of sulfuric acid and only trace amounts of water. Its atmosphere is heavier than that of any other planet. It is leading to a surface pressure that’s over 90 times that of Earth — similar to the pressure that exists 3,300 feet (1,000 meters) deep in the ocean.
Incredibly, however, is that early in Venus’ history, the planet may have actually been habitable, according to models from researchers at NASA’s Goddard Institute for Space Studies and other studies.
Venus’ surface is extremely dry. During its evolution, ultraviolet rays from the sun evaporated water quickly, keeping the planet in a prolonged molten state. There is no liquid water on its surface today. Because the scorching heat created by its ozone-filled atmosphere would cause water to immediately boil away.
Roughly two-thirds of the Venusian surface is covered by flat, smooth plains that are marred by thousands of volcanoes, some of which are still active today, ranging from about 0.5 to 150 miles (0.8 to 240 km) wide, with lava flows carving long, winding canals that are up to more than 3,000 miles (5,000 km) in length.
Six mountainous regions make up about one-third of the Venusian surface. One mountain range, called Maxwell, is about 540 miles (870 km) long. And it reaches up to some 7 miles (11.3 km) high, making it the highest feature on the planet.
Venus also possesses a number of surface features that are unlike anything on Earth. For example, Venus has coronae, or crowns — ring-like structures that range from roughly 95 to 1,300 miles (155 to 2100 km) wide. Scientists believe these formed when hot material beneath the planet’s crust rose up, warping the planet’s surface. Venus also has tesserae, or tiles — raised areas in which many ridges and valleys have formed in different directions.
With conditions on Venus that could be described as infernal, the ancient name for Venus — Lucifer — seems to fit. However, the name doesn’t carry any fiendish connotations; Lucifer means “light-bringer,” and when seen from Earth, Venus is brighter than any other planet or even any star in the night sky. Because of its highly reflective clouds and its closeness to our planet.
The order of the planets in the solar system, starting nearest the sun and working outward is the following. Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and then the possible Planet Nine.
Ever since the discovery of Pluto in 1930, kids grew up learning that the solar system has nine planets. That all changed in the late 1990s when astronomers started arguing about whether Pluto was indeed a planet. In a highly controversial decision, the International Astronomical Union ultimately decided in 2006 to designate Pluto as a “dwarf planet,” reducing the list of the solar system’s true planets to just eight.
If you insist on including Pluto, it would come after Neptune on the list. Pluto is truly way out there and on a wildly tilted, elliptical orbit.
More recent Venus missions include ESA’s Venus Express and Japan’s Akatsuki Venus Climate Orbiter (orbiting since 2016). NASA’s Parker Solar Probe has made multiple flybys of Venus. And on July 11, 2020, the probe came within 516 miles of the surface.
In June 2021 three new missions to Venus were announced:
- On June 2, 2021, NASA announced it had selected two new missions to Venus as part of the agency’s Discovery Program. The missions are expected to launch in the 2028-2030 timeframe.
- On June 10, 2021, the European Space Agency (ESA) announced the selection of EnVision to make detailed observations of Venus. As a key partner in the mission, NASA is providing the Synthetic Aperture Radar, called VenSAR, to make high-resolution measurements of the planet’s surface features.
Thank you for staying with this post “what is the 2nd planet from the sun” until the end.