Mars Orbiter Mission (Mangalyaan) – India Mars Orbiter - 15 kg - (November 5, 2013) The Indian Mars Orbiter Mission was launched on November 5, 2013, from the Satish Dhawan Space Center. It was inserted into orbit around Mars on September 24, 2014 and completed its planned 160-day mission duration in March 2015. Speaking at the Mars Society's 23rd Annual Convention earlier today, SpaceX C.E.O. And Chief Engineer Elon Musk shared his thoughts on the company's Starship launch vehicle platform and Mars missions.
- Mars as seen from Earth
- The atmosphere
- Character of the surface
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Mars Orbital Velocity
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Mars, fourth planet in the solar system in order of distance from the Sun and seventh in size and mass. It is a periodically conspicuous reddish object in the night sky. Mars is designated by the symbol ♂.
Sometimes called the Red Planet, Mars has long been associated with warfare and slaughter. It is named for the Roman god of war. As long as 3,000 years ago, Babylonian astronomer-astrologers called the planet Nergal for their god of death and pestilence. The planet’s two moons, Phobos (Greek: “Fear”) and Deimos (“Terror”), were named for two of the sons of Ares and Aphrodite (the counterparts of Mars and Venus, respectively, in Greek mythology).
| Planetary data for Mars | |
|---|---|
| *Time required for the planet to return to the same position in the sky relative to the Sun as seen from Earth. | |
| mean distance from Sun | 227,943,824 km (1.5 AU) |
| eccentricity of orbit | 0.093 |
| inclination of orbit to ecliptic | 1.85° |
| Martian year (sidereal period of revolution) | 686.98 Earth days |
| visual magnitude at mean opposition | −2.01 |
| mean synodic period* | 779.94 Earth days |
| mean orbital velocity | 24.1 km/sec |
| equatorial radius | 3,396.2 km |
| north polar radius | 3,376.2 km |
| south polar radius | 3,382.6 km |
| surface area | 1.44 × 108 km2 |
| mass | 6.417 × 1023 kg |
| mean density | 3.93 g/cm3 |
| mean surface gravity | 371 cm/sec2 |
| escape velocity | 5.03 km/sec |
| rotation period (Martian sidereal day) | 24 hr 37 min 22.663 sec |
| Martian mean solar day (sol) | 24 hr 39 min 36 sec |
| inclination of equator to orbit | 25.2° |
| mean surface temperature | 210 K (−82 °F, −63 °C) |
| typical surface pressure | 0.006 bar |
| number of known moons | 2 |
Mars Orbit Time
In recent times Mars has intrigued people for more-substantial reasons than its baleful appearance. The planet is the second closest to Earth, after Venus, and it is usually easy to observe in the night sky because its orbit lies outside Earth’s. It is also the only planet whose solid surface and atmospheric phenomena can be seen in telescopes from Earth. Centuries of assiduous studies by earthbound observers, extended by spacecraft observations since the 1960s, have revealed that Mars is similar to Earth in many ways. Like Earth, Mars has clouds, winds, a roughly 24-hour day, seasonal weather patterns, polar ice caps, volcanoes, canyons, and other familiar features. There are intriguing clues that billions of years ago Mars was even more Earth-like than today, with a denser, warmer atmosphere and much more water—rivers, lakes, flood channels, and perhaps oceans. By all indications Mars is now a sterile frozen desert. However, close-up images of dark streaks on the slopes of some craters during Martian spring and summer suggest that at least small amounts of water may flow seasonally on the planet’s surface, and radar reflections from a possible lake under the south polar cap suggest that water may still exist as a liquid in protected areas below the surface. The presence of water on Mars is considered a critical issue because life as it is presently understood cannot exist without water. If microscopic life-forms ever did originate on Mars, there remains a chance, albeit a remote one, that they may yet survive in these hidden watery niches. In 1996 a team of scientists reported what they concluded to be evidence for ancient microbial life in a piece of meteorite that had come from Mars, but most scientists have disputed their interpretation.
Since at least the end of the 19th century, Mars has been considered the most hospitable place in the solar system beyond Earth both for indigenous life and for human exploration and habitation. At that time, speculation was rife that the so-called canals of Mars—complex systems of long, straight surface lines that very few astronomers had claimed to see in telescopic observations—were the creations of intelligent beings. Seasonal changes in the planet’s appearance, attributed to the spread and retreat of vegetation, added further to the purported evidence for biological activity. Although the canals later proved to be illusory and the seasonal changes geologic rather than biological, scientific and public interest in the possibility of Martian life and in exploration of the planet has not faded.
During the past century Mars has taken on a special place in popular culture. It has served as inspiration for generations of fiction writers from H.G. Wells and Edgar Rice Burroughs in the heyday of the Martian canals to Ray Bradbury in the 1950s and Kim Stanley Robinson in the ’90s. Mars has also been a central theme in radio, television, and film, perhaps the most notorious case being Orson Welles’s radio-play production of H.G. Wells’s novel War of the Worlds, which convinced thousands of unwitting listeners on the evening of October 30, 1938, that beings from Mars were invading Earth. The planet’s mystique and many real mysteries remain a stimulus to both scientific inquiry and human imagination to this day.
Mars Orbital Radius
Mars distance from the Sun is 230 million km and its orbital period is equal to 687 Earth days. For this planet, the solar day is only a bit longer than that of the Earth’s day which is 24 hours, 39 minutes and 35.244 seconds. An entire Martian year would equal 1.8809 in Earth years.
Mars’ axial tilt is 25.19 degrees, which is quite similar to that of our own planet and in this way, seasons in Mars are very much like the seasons that we have here on Earth. However, on Mars, they are almost twice as long because of the fact that the planet has significantly longer years compared to us. At the moment, the orientation of Mars’ North Pole is close to Deneb.
The planet has passed its perihelion in April 2009 and its aphelion in May 2007. It would reach its next perihelion in May 2011. Mars has a rather pronounced orbital eccentricity, which is about 0.09, compared to the other planets in the Solar System. The only other planet that shows greater eccentricity would be Mercury. For the last 35,000 years, Mars’ orbit has grown even more eccentric due to the gravitation effects that the other planets have on it. In fact, the closest distance between our planet and Mars would continuously decrease for the next 25,000 years.
As for its moons, Mars has two tiny natural ones. Phobos and Deimos orbit quite close to the planets. Currently, from what scientists know of their composition, it is believed that both moons were captured asteroids but this has never been completely ascertained nor confirmed.
Where Is Mars Right Now
More about the Planet Mars