Olympus Mons, Tharsis Bulge trio of volcanoes and Valles Marineris from ISRO's Mars Orbiter Mission. Note the clouds and south polar ice cap. Credit: ISRO
MOM celebrates 1 Year at Mars
Olympus Mons, Tharsis Bulge trio of volcanoes and Valles Marineris from ISRO’s Mars Orbiter Mission. Note the clouds and south polar ice cap. Credit: ISRO[/caption]
The Mars Orbiter Mission, or MOM, is India’s first deep space voyager to explore beyond the confines of her home planets influence and successfully arrived at the Red Planet after the “history creating” orbital insertion maneuver on Sept. 23/24, 2014 following a ten month interplanetary journey from Earth.
The MOM orbiter was designed and developed by the Indian Space Research Organization (ISRO), India’s space agency, which is the equivalent of NASA.
“Mars Orbiter spacecraft marks one year of its life around the Red Planet today [Sept. 24, IST],” said ISRO. It was primarily designed as a technology demonstrator but is also outfitted with significant science instruments.
Shri A S Kiran Kumar, Chairman ISRO (centre) releasing the Mars Orbiter Mission (MOM) Mars Atlas with Dr. Y V N Krishnamoorthy, Scientific Secretary ISRO (left); Dr. Annadurai M, Director ISRO Satellite Centre, Shri Tapan Misra, Director Space Application Centre ISRO, Shri Deviprasad Karnik, Director Public Relations Unit ISRO. Credit: ISRO
The probe is equipped with a 15 kg (33 lb) suite of five indigenous instruments to conduct meaningful science – including the tri color Mars Color Camera imager (MCC) and a methane gas sniffer (MSM) to study the Red Planet’s atmosphere, morphology, mineralogy and surface features. Methane on Earth originates from both geological and biological sources – and could be a potential marker for the existence of Martian microbes.
“After successfully completing one year of the mission life around Mars, now a large data set has been acquired by all five payloads of MOM,” ISRO stated.
To mark the one year anniversary ISRO released a new 120 page “Mars Atlas” of imagery and results, which can be downloaded from the ISRO website.
“The images from MCC have provided unique information about Mars at varying spatial resolutions. It has obtained Mars Global data showing clouds, dust in atmosphere and surface albedo variations, when acquired from apoapsis at around 72000 km.”
“On the other hand high resolution images acquired from periapsis show details of various morphological features on the surface of Mars. Some of these images have been showcased in this atlas. The images have been categorized depending upon the Martian surface and atmospheric processes.”
This view over the Ophir Chasma canyon on the Martian surface was taken by the Mars Colour Camera aboard India’s Mars Orbiter Mission (MOM). Ophir Chasma is a canyon in the Coprates quadrangle located at 4° south latitude and 72.5° west longitude. It is part of the Valles Marineris canyon system. Credit: ISRO
MOM was built in record time and for a budget of $73 million.
“The MOM spacecraft was designed, built and launched in record period of less than two years,” ISRO explained. “MOM carried five science instruments collecting data on surface geology, morphology, atmospheric processes, surface temperature and atmospheric escape process.”
Valles Marineris from India’s Mars Mission. Credit: ISRO
MOM’s Martian arrival was webcast worldwide with an elaborate ceremony that included India’s prime minister who beamed with pride in the team and the nation at that time.
“India has successfully reached Mars!” declared Indian prime minister Narendra Modi, who watched the events unfold from mission control at ISRO’s Telemetry, Tracking and Command Network (ISTRAC) in Bangalore, on Sept. 24, 2014.
“History has been created today. We have dared to reach out into the unknown and have achieved the near-impossible. I congratulate all ISRO scientists as well as all my fellow Indians on this historic occasion.”
MOM swoops around the Red Planet in a highly elliptical orbit whose nearest point to Mars (periapsis) is about 421.7 km and farthest point (apoapsis) is about 76,993.6 km, according to ISRO
ISRO’s Mars Orbiter Mission captures spectacular portrait of the Red Planet and swirling dust storms with the on-board Mars Color Camera from an altitude of 74500 km on Sept. 28, 2014. Credit: ISRO
Upon MOM’s arrival, India became the newest member of an elite club of only four entities who have launched probes that successfully investigated Mars – following the Soviet Union, the United States and the European Space Agency (ESA).
MOM was launched on Nov. 5, 2013 from India’s spaceport at the Satish Dhawan Space Centre, Sriharikota, atop the nations indigenous four stage Polar Satellite Launch Vehicle (PSLV) which placed the probe into its initial Earth parking orbit.
ISRO’s Mars Orbiter Mission captures the limb of Mars with the Mars Color Camera from an altitude of 8449 km soon after achieving orbit on Sept. 23/24, 2014. . Credit: ISRO
The Indian probe arrived just two days after NASA’s MAVEN Mars orbiter, the first mission specifically targeted to study Mars tenuous upper atmosphere and the escape rates of atmospheric constituents.
The $73 million MOM mission was initially expected to last at least six months. In March 2015, ISRO extended the mission duration for another six months since its healthy, the five science instruments were operating fine and it had sufficient fuel reserves.
Indeed MOM has enough fuel to continue gather data and images for years to come if the instruments and spacecraft continue to function nominally.
“The Mars Orbiter Mission still has some 45 kg of fuel left which could, in theory, keep the mission going for at least 15 years,” ISRO told The Hindu.
“One cannot get a better bang for the buck! According to ISRO, for normal housekeeping operations and orbit maintenance only about two kg of fuel is necessary per year.”
Including MOM, Earth’s invasion fleet at the Red Planet numbers a total of seven spacecraft comprising five orbiters from NASA, ESA and ISRO as well as the sister pair of mobile surface rovers from NASA – Curiosity and Opportunity.
Spectacular 3D view of Arsia Mons, a huge volcano on Mars, taken by camera on India’s Mars Orbiter Mission (MOM). Credit: ISRO
Stay tuned here for Ken’s continuing Earth and planetary science and human spaceflight news.
First ever image of Earth Taken by Mars Color Camera aboard India’s Mars Orbiter Mission (MOM) spacecraft while orbiting Earth and before the Trans Mars Insertion firing on Dec. 1, 2013. Image is focused on the Indian subcontinent. Credit: ISRO
Special Guests:
Maggie Scholtz (@martianmagster), who is a Mechanical Engineer working at JPL. She worked on the Curiosity Rover, primarily on the development of the drill and sampling system.
Watched @MartianMovie on @Space_Station last night! Today working towards our #JourneyToMars during my #YearInSpace!” Credit: NASA/Scott Kelly
Video caption: ‘The Martian’ Star Matt Damon Discusses NASA’s Journey to Mars. Credit: NASA
The excitement is building for the worldwide movie premiere of ‘The Martian’ on Oct. 2.
Based on the bestselling book by Andy Weir, ‘The Martian’ tells the story of how NASA astronaut Mark Watney, played by Matt Damon, is accidentally stranded on the surface of Mars during a future manned expedition, after a sudden and unexpectedly fierce dust storm forces the rest of the crew to quickly evacuate after they believe he is dead.
In the video above, Matt Damon discusses NASA’s ongoing real life efforts focused on turning science fiction dreams into reality and sending astronauts to Mars.
Watney actually survived the storm but lost contact with NASA. The film recounts his ingenious years long struggle to survive, figure out how to tell NASA he is alive and send a rescue crew before he starves to death on a planet where nothing grows. Watney’s predicament is a survival lesson to all including NASA.
‘The Martian’ was written by Andy Weir in 2010 and has now been produced as a major Hollywood motion picture starring world famous actor Matt Damon and directed by the world famous director Ridley Scott from 20th Century Fox.
NASA’s overriding strategic goal is to send humans on a ‘Journey to Mars’ by the 2030s.
‘The Martian’ is a rather realistic portrayal of how NASA might accomplish the ‘Journey to Mars.’
“Sending people to Mars and returning them safely is the challenge of a generation,” says Damon in the video.
“The boot prints of astronauts will follow the rover tracks [of NASA’s Curiosity rover] thanks to innovations happening today.”
“NASA’s Journey to Mars begins on the International Space Station (ISS) .. where we are learning how humans can thrive over long periods without gravity.”
The current six person crew serving aboard the ISS even got a sneak preview of The Martian this past weekend!
Gleeful NASA astronaut Scott Kelly, commander of the Expedition 45 crew, just tweeted a photo of the crew watching ‘The Martian’ while soaring some 250 miles (400 kilometers) above Earth.
“Watched @MartianMovie on @Space_Station last night! Today working towards our #JourneyToMars during my #YearInSpace!” tweeted NASA astronaut Scott Kelly.
Kelly comprises one half of the first ever ‘1 Year ISS Crew’ along with Russian cosmonaut Mikhail Kornienko, aimed at determining the long term physical and psychological effects on the human body of people living and working in the weightlessness of space.
The 1 Year ISS mission is an important data gathering milestone on the human road to Mars since the round trip time to the Red Planet and back will take approximately 3 years or more.
The first unmanned test flight of SLS/Orion is slated for Nov. 2018. The first manned flight could occur between 2021 and 2023 – read my new report here.
“The Journey to Mars will forever change our history books … and expand our human presence deeper into the solar system,” says Damon.
THE MARTIAN features a star studded cast that includes Matt Damon, Jessica Chastain, Kristen Wiig, Kate Mara, Michael Pena, Jeff Daniels, Chiwetel Ejiofor, and Donald Glover.
Matt Damon stars as NASA astronaut Mark Watney in ‘The Martian.’ Credit: 20th Century Fox
“NASA has endorsed “The Martian’” Jim Green, NASA’s Director of Planetary Sciences, told Universe Today. Green served as technical consultant on the film.
I have read the book (I’m a professional chemist) and highly recommend it to everyone.
The Martian is all about how Watney uses his botany and chemistry skills to “Science the Sh.. out of it” to grow food and survive.
Learning how to live of the land will be a key hurdle towards enabling long term space voyages.
Kelly and his ISS cremates took a big first step towards putting that theory into practice when they recently grew, harvested and ate the first space grown NASA lettuce on the ISS using the Veggie experimental rack – detailed in my recent story here.
NASA Astronauts Kjell Lindgren (center) and Scott Kelly (right) and Kimiya Yui (left) of Japan consume space grown food for the first time ever, from the Veggie plant growth system on the International Space Station. Credit: NASA TV
Here’s the second official trailer of “The Martian:
Stay tuned here for Ken’s continuing Earth and planetary science and human spaceflight news.
Veggie demonstration apparatus growing red romaine lettuce under LED lights in the Space Station Processing Facility at NASA’s Kennedy Space Center. Credit: Ken Kremer/kenkremer.com
Mars and Regulus are already close. This photo was taken this morning (Sept. 21) about an hour 10 minutes before sunrise. Credit: Bob King
I was up before dawn today hoping to find the returning comet 205P/Giacobini and a faint new supernova in the galaxy IC 1776 in Pisces. I was fortunate to see them both. But the morning held a pleasant surprise I hadn’t anticipated. Venus rose brilliantly in the east followed by the much dimmer planet Mars some 10° to its lower left. And there, not more than a couple degrees below Mars, shone Leo’s brightest star, Regulus. At first glance both appeared about equally bright, but looking closer, it was clear that Regulus, at magnitude +1.3, bested Mars by nearly half a magnitude. What was especially appealing was the color contrast between the two with Mars’ dusty, rusty surface so different from the pure white radiance of Regulus.
On Friday morning September 25, Mars and Regulus will be just 0.8 degrees apart in the eastern sky below brilliant Venus at dawn. They’ll be nearly as close Thursday morning. Source: Stellarium
While star and planet are both close enough to catch the eye, they’re headed for an excellent conjunction Thursday and Friday mornings, September 24 and 25. The actual time of closest approach, when star and planet will be separated by just 0.8°, occurs around 11 p.m. CDT — before Mars rises for skywatchers in the Americas and Canada, but about perfect for European and African observers.
Just the same, everyone around the planet will see them less than a degree apart low in the eastern sky about 90 minutes to an hour before sunrise on those dates. Joining the scene will be Venus, now spectacularly bright against the deep blue, early dawn, and Jupiter, bringing up the rear further lower down in Leo’s tail.
Regulus is a main sequence star like the Sun but hotter. It spins so fast that it’s stretched into an oblate spheroid 4.3 times the diameter of the Sun.
Regulus, Latin for “little king”, may have received that name because it’s the brightest star in the Leo the Lion, king of the beasts. The ancient Greeks knew it by the same name, Basiliscos, as did the Babylonians before them who called it Lugal (king). Regulus is the only 1st magnitude star to sit almost directly on the ecliptic, the path followed by the Moon, Sun and planets through the sky. That means it gets regular visitors. Mars this week; Venus and the crescent Moon both on October 8. Few bright stars are as welcoming of unannounced guests.
I encourage beginning and advanced astrophotographers alike to capture the Regulus-Mars conjunction using a tripod-mounted camera. Just find an attractive setting and make a series of exposures at ISO 800 with a standard 35mm lens. Click here to find out when the Sun rises, so you’ll know what time to back up from to see the event. Now that fall brings much later sunrises, it’s not so hard anymore to catch dawn sky offerings.
It’s also a delight to see the Red Planet again, which will come to a close opposition in the constellation Scorpius next May. Let the fun begin!
Special Guests:
Dr. Sara Seager, whose research focuses on computer models of exoplanet atmospheres, interiors, and biosignatures. Her favorite projects involve the search for planets like Earth with signs of life
on them.
Large-scale crossbedding in the sandstone of this ridge on a lower slope of Mars' Mount Sharp is typical of windblown sand dunes that have petrified. NASA's Curiosity Mars rover used its Mastcam to capture this vista on Aug. 27, 2015, Sol 1087. Similarly textured sandstone is common in the U.S. Southwest. Credits: NASA/JPL-Caltech/MSSS
Large-scale crossbedding in the sandstone of this ridge on a lower slope of Mars’ Mount Sharp is typical of windblown sand dunes that have petrified. NASA’s Curiosity Mars rover used its Mastcam to capture this vista on Aug. 27, 2015, Sol 1087. Similarly textured sandstone is common in the U.S. Southwest. Credits: NASA/JPL-Caltech/MSSS
See Sol 1100 mosaic below [/caption]
NASA’s SUV-sized Curiosity rover has arrived at a beautiful Martian vista displaying a huge deposit of magnificently petrified sand dunes that look remarkably like some commonly found on Earth and native to the deserts of the U.S. Southwest.
The petrified sand dunes were discovered amongst an area of dark sandstone along a ridge at the lower slope of Mars’ Mount Sharp. They are now being explored in detail by the six wheeled rover in a geologic feature dubbed the Stimson unit.
“The team is considering where to drill next within the Stimson sandstone and we are looking for the best light toned areas to check for mineralogical signs of water-rock reaction,” says John Bridges, rover team member from the University of Leicester, England, in the latest mission update from today, September 12, 2015.
Curiosity looks toward fabulous canyons and buttes at the base of Mount Sharp from the Stimson sand dunes on Mars on Sol 1100, Sept. 10 2015 in this photo mosaic stitched from Mastcam color camera raw images. Credit: NASA/JPL/MSSS/Ken Kremer/kenkremer.com/Marco Di Lorenzo
Curiosity also discovered large-scale crossbedding in the sandstone that were formed by the action of Martian winds.
“This sandstone outcrop — part of a geological layer that Curiosity’s science team calls the Stimson unit — has a structure called crossbedding on a large scale that the team has interpreted as deposits of sand dunes formed by wind,” according to the rover team.
So Curiosity was commanded by her handlers back on Earth to capture an array of high resolution imagery as part of detailed investigation of the area for up close and contact science.
Dozens of images were taken with the pair of high resolution Mastcam color cameras on the robots mast and combined into the panoramic scene show above and another shown below with a scalebar the length of a tall human, 6.6 feet or 200 centimeters.
Large-scale crossbedding in the sandstone of this ridge on a lower slope of Mars’ Mount Sharp is typical of windblown sand dunes that have petrified. NASA’s Curiosity Mars rover used its Mastcam to capture this vista on Aug. 27, 2015. Similarly textured sandstone is common in the U.S. Southwest. Credits: NASA/JPL-Caltech/MSSS
The images were taken on Aug. 27, 2015, corresponding to Sol 1087 of the rover’s work on Mars, using both the 34 millimeter-focal-length lens and the 100 mm millimeter-focal-length telephoto Mastcam camera lenses that function as Curiosity’s left and right eyes.
The panorama spans the Martian terrain looking from the east, at left, to the south-southwest at right.
“Some of the dark sandstone in the area …. shows texture and inclined bedding structures characteristic of deposits that formed as sand dunes, then were cemented into rock” say officials.
“Sets of bedding laminations lie at angles to each other.”
Since taking the panorama in late August, the team has driven Curiosity around the area to collect more measurements with her state of the art science instruments.
Later this month, Curiosity will drill into an outcrop at the Stimson unit sandstone for collection and feed it for analysis into the pair of on board chemistry labs – SAM and CheMin- located inside the rover’s belly.
Curiosity already carried out initial contact science in the area by extending the robotic arm to rock targets for investigation with the arm mounted instruments, including the MAHLI camera and APXS spectrometer.
Curiosity “investigated an outcrop of the Stimson unit … and conducted successful contact science,” says Lauren Edgar, Research Geologist at the USGS Astrogeology Science Center and an MSL science team member, in a mission update.
Scientists will select the Stimson drill target soon.
Curiosity rover explores around the Stimson unit at the base of Mount Sharp on Mars on Sol 1095, Sept. 5, 2015 in this photo mosaic stitched from Mastcam color camera raw images. Credit: NASA/JPL/MSSS/Marco Di Lorenzo/Ken Kremer/kenkremer.com
Why explore outcrops at Stimson?
“The Stimson unit overlies a layer of mudstone that was deposited in a lake environment. Curiosity has been examining successively higher and younger layers of Mount Sharp, starting with the mudstone at the mountain’s base, for evidence about changes in the area’s ancient environment.”
Curiosity’s prior drill campaign was recently conducted at the “Buckskin” outcrop target in early August 2015. Buckskin was very notable for being the first high silica rock drilling target of the mission.
Curiosity extends robotic arm and conducts sample drilling at “Buckskin” rock target at bright toned “Lion” outcrop at the base of Mount Sharp on Mars, seen at right. Gale Crater eroded rim seen in the distant background at left, in this composite multisol mosaic of navcam raw images taken to Sol 1059, July 30, 2015. Navcam camera raw images stitched and colorized. Inset: MAHLI color camera up close image of full depth drill hole at “Buckskin” rock target on Sol 1060. Credit: NASA/JPL-Caltech/MSSS/Ken Kremer/kenkremer.com/Marco Di Lorenzo
Stimson and Buckskin sit at the base of Mount Sharp, a huge layered mountain that dominates the center of the 96 mile-wide (154 kilometers-wide) Gale Crater landing site.
Exploring the sedimentary layers of Mount Sharp, which towers 3.4 miles (5.5 kilometers) into the Martian sky, is the primary destination and goal of the rovers long term scientific expedition on the Red Planet.
As of today, Sol 1102, September 12, 2015, she has driven some 6.9 miles (11.1 kilometers) kilometers and taken over 268,000 amazing images.
Curiosity has already accomplished her primary objective of discovering a habitable zone on the Red Planet – at the Yellowknife Bay area – that contains the minerals necessary to support microbial life in the ancient past when Mars was far wetter and warmer billions of years ago.
Curiosity rover scans toward south east around Marias Pass area at the base of Mount Sharp on Mars on Sol 1074, Aug. 14, 2015 in this photo mosaic stitched from Mastcam color camera raw images. Credit: NASA/JPL/MSSS/Marco Di Lorenzo/Ken Kremer/kenkremer.com
Stay tuned here for Ken’s continuing Earth and planetary science and human spaceflight news.
The Moon, just a couple days before new phase and the upcoming partial solar eclipse, joins Venus and Mars in the dawn sky on Thursday Sept. 10. Well below the triplet, look for returning Jupiter. Source: Stellarium
The dawn sky’s where it’s happening. With Saturn swiftly sinking westward at dusk, bright planets have become scarce in the evening hours. But if you get up early and look east, you’ll discover where the party is. Venus, Mars and now Jupiter have the dance floor.
Tale of two crescents. A montage of the thick crescent Moon and crescent Venus photographed earlier this month. Credit: Tom Ruen
What’s more, the sky gods have seen fit to roll a thin crescent Moon alongside Venus Thursday morning (Sept. 10). This lovely twinning of crescents is best seen about 75 minutes to an hour before sunrise. All you need is a pair of 10x binoculars to see the peewee Venusian version. Its waning crescent phase closely mimics the Moon’s.
From the U.S., the separation between the two will vary from 3° for the East Coast to 4.5° for the West. European and African skywatchers will witness the actual conjunction with the Moon gliding 2.5° north of the planet.
Venus is very bright, making it easy to see in the daytime if you know where to look. Try using the thin Moon soon after sunrise (7:30 a.m. local time shown here) to spot Venus. Aim and focus your binoculars on the Moon, then glide up and to the right to find Venus. If you succeed, lower the binoculars and see if you can spot it without optical aid. Source: Stellarium
Much fainter Mars, checking in at magnitude +1.8, lies 6° to the left or east of the Moon. It thrills me to see Mars begin a new apparition with its return to the morning sky. Next year, the Red Planet reaches opposition on May 22 in the constellation Scorpius, when it will be brighter than Sirius and more than 18 arc seconds across, its biggest and closest since 2005.
Remember Jupiter? We lost it in the solar glare more than a month ago, but if you can find a location with a nice, open eastern horizon, you can welcome the ever-jovial planet back Thursday. Bring binoculars just in case! Jove’s only a few degrees high in moderately-bright twilight.
The bright sunlit crescent contrasts with the darker lighting of twice-reflected light contributed by own planet. Credit: Bob King
When you look at the Moon Thursday, most of it will be illuminated not by sunlight but by Earth-light called earthshine. This smoky, dark glow results from sunlight bouncing off the globe into space to softly light the otherwise shadowed portion of the Moon. The effect is most pleasing to the eye and remarkable in binoculars, which reveal lunar seas and even larger craters shrouded in blue-dark. Don’t miss it!
The Universe is a very big place, and we occupy a very small corner of it. Known as the Solar System, our stomping grounds are not only a tiny fraction of the Universe as we know it, but is also a very small part of our galactic neighborhood (aka. the Milky Way Galaxy). When it comes right down to it, our world is just a drop of water in an endless cosmic sea.
Nevertheless, the Solar System is still a very big place, and one which is filled with its fair share of mysteries. And in truth, it was only within the relatively recent past that we began to understand its true extent. And when it comes to exploring it, we’ve really only begun to scratch the surface.
Discovery:
With very few exceptions, few people or civilizations before the era of modern astronomy recognized the Solar System for what it was. In fact, the vast majority of astronomical systems posited that the Earth was a stationary object and that all known celestial objects revolved around it. In addition, they viewed it as being fundamentally different from other stellar objects, which they held to be ethereal or divine in nature.
Although there were some Greek, Arab and Asian astronomers during Antiquity and the Medieval period who believed that the universe was heliocentric in nature (i.e. that the Earth and other bodies revolved around the Sun) it was not until Nicolaus Copernicus developed his mathematically predictive model of a heliocentric system in the 16th century that it began to become widespread.
Galileo (1564 – 1642) would often show people how to use his telescope to view the sky in Saint Mark’s square in Venice. Note the lack of adaptive optics. Credit: Public Domain
During the 17th-century, scientists like Galileo Galilei, Johannes Kepler, and Isaac Newton developed an understanding of physics which led to the gradual acceptance that the Earth revolves round the Sun. The development of theories like gravity also led to the realization that the other planets are governed by the same physical laws as Earth.
The widespread use of the telescope also led to a revolution in astronomy. After Galileo discovered the moons of Jupiter in 1610, Christian Huygens would go on to discover that Saturn also had moons in 1655. In time, new planets would also be discovered (such as Uranus and Neptune), as well as comets (such as Halley’s Comet) and the Asteroids Belt.
By the 19th century, three observations made by three separate astronomers determined the true nature of the Solar System and its place the universe. The first was made in 1839 by German astronomer Friedrich Bessel, who successfully measured an apparent shift in the position of a star created by the Earth’s motion around the Sun (aka. stellar parallax). This not only confirmed the heliocentric model beyond a doubt, but revealed the vast distance between the Sun and the stars.
In 1859, Robert Bunsen and Gustav Kirchhoff (a German chemist and physicist) used the newly invented spectroscope to examined the spectral signature of the Sun. They discovered that it was composed of the same elements as existed on Earth, thus proving that Earth and the heavens were composed of the same elements.
With parallax technique, astronomers observe object at opposite ends of Earth’s orbit around the Sun to precisely measure its distance. Credit: Alexandra Angelich, NRAO/AUI/NSF.
Then, Father Angelo Secchi – an Italian astronomer and director at the Pontifical Gregorian University – compared the spectral signature of the Sun with those of other stars, and found them to be virtually identical. This demonstrated conclusively that our Sun was composed of the same materials as every other star in the universe.
Further apparent discrepancies in the orbits of the outer planets led American astronomer Percival Lowell to conclude that yet another planet, which he referred to as “Planet X“, must lie beyond Neptune. After his death, his Lowell Observatory conducted a search that ultimately led to Clyde Tombaugh’s discovery of Pluto in 1930.
Also in 1992, astronomers David C. Jewitt of the University of Hawaii and Jane Luu of the MIT discovered the Trans-Neptunian Object (TNO) known as (15760) 1992 QB1. This would prove to be the first of a new population, known as the Kuiper Belt, which had already been predicted by astronomers to exist at the edge of the Solar System.
Further investigation of the Kuiper Belt by the turn of the century would lead to additional discoveries. The discovery of Eris and other “plutoids” by Mike Brown, Chad Trujillo, David Rabinowitz and other astronomers would lead to the Great Planet Debate – where IAU policy and the convention for designating planets would be contested.
The Sun contains 99.86% of the system’s known mass, and its gravity dominates the entire system. Most large objects in orbit around the Sun lie near the plane of Earth’s orbit (the ecliptic) and most planets and bodies rotate around it in the same direction (counter-clockwise when viewed from above Earth’s north pole). The planets are very close to the ecliptic, whereas comets and Kuiper belt objects are frequently at greater angles to it.
It’s four largest orbiting bodies (the gas giants) account for 99% of the remaining mass, with Jupiter and Saturn together comprising more than 90%. The remaining objects of the Solar System (including the four terrestrial planets, the dwarf planets, moons, asteroids, and comets) together comprise less than 0.002% of the Solar System’s total mass.
The Sun and planets to scale. Credit: Illustration by Judy Schmidt, texture maps by Björn Jónsson
Astronomers sometimes informally divide this structure into separate regions. First, there is the Inner Solar System, which includes the four terrestrial planets and the Asteroid Belt. Beyond this, there’s the outer Solar System that includes the four gas giant planets. Meanwhile, there’s the outermost parts of the Solar System are considered a distinct region consisting of the objects beyond Neptune (i.e. Trans-Neptunian Objects).
Most of the planets in the Solar System possess secondary systems of their own, being orbited by planetary objects called natural satellites (or moons). In the case of the four giant planets, there are also planetary rings – thin bands of tiny particles that orbit them in unison. Most of the largest natural satellites are in synchronous rotation, with one face permanently turned toward their parent.
The Sun, which comprises nearly all the matter in the Solar System, is composed of roughly 98% hydrogen and helium. The terrestrial planets of the Inner Solar System are composed primarily of silicate rock, iron and nickel. Beyond the Asteroid Belt, planets are composed mainly of gases (such as hydrogen, helium) and ices – like water, methane, ammonia, hydrogen sulfide and carbon dioxide.
Objects farther from the Sun are composed largely of materials with lower melting points. Icy substances comprise the majority of the satellites of the giant planets, as well as most of Uranus and Neptune (hence why they are sometimes referred to as “ice giants”) and the numerous small objects that lie beyond Neptune’s orbit.
Together, gases and ices are referred to as volatiles. The boundary in the Solar System beyond which those volatile substances could condense is known as the frost line, which lies roughly 5 AU from the Sun. Within the Kuiper Belt, objects and planetesimals are composed mainly of these materials and rock.
Formation and Evolution:
The Solar System formed 4.568 billion years ago from the gravitational collapse of a region within a large molecular cloud composed of hydrogen, helium, and small amounts of heavier elements fused by previous generations of stars. As the region that would become the Solar System (known as the pre-solar nebula) collapsed, conservation of angular momentum caused it to rotate faster.
The center, where most of the mass collected, became increasingly hotter than the surrounding disc. As the contracting nebula rotated faster, it began to flatten into a protoplanetary disc with a hot, dense protostar at the center. The planets formed by accretion from this disc, in which dust and gas gravitated together and coalesced to form ever larger bodies.
Due to their higher boiling points, only metals and silicates could exist in solid form closer to the Sun, and these would eventually form the terrestrial planets of Mercury, Venus, Earth, and Mars. Because metallic elements only comprised a very small fraction of the solar nebula, the terrestrial planets could not grow very large.
In contrast, the giant planets (Jupiter, Saturn, Uranus, and Neptune) formed beyond the point between the orbits of Mars and Jupiter where material is cool enough for volatile icy compounds to remain solid (i.e. the frost line).
The ices that formed these planets were more plentiful than the metals and silicates that formed the terrestrial inner planets, allowing them to grow massive enough to capture large atmospheres of hydrogen and helium. Leftover debris that never became planets congregated in regions such as the asteroid belt, Kuiper belt, and Oort cloud.
Within 50 million years, the pressure and density of hydrogen in the center of the protostar became great enough for it to begin thermonuclear fusion. The temperature, reaction rate, pressure, and density increased until hydrostatic equilibrium was achieved.
At this point, the Sun became a main-sequence star. Solar wind from the Sun created the heliosphere and swept away the remaining gas and dust from the protoplanetary disc into interstellar space, ending the planetary formation process.
The terrestrial planets of our Solar System at approximately relative sizes. From left, Mercury, Venus, Earth and Mars. Credit: Lunar and Planetary Institute
The Solar System will remain roughly as we know it today until the hydrogen in the core of the Sun has been entirely converted to helium. This will occur roughly 5 billion years from now and mark the end of the Sun’s main-sequence life. At this time, the core of the Sun will collapse, and the energy output will be much greater than at present.
The outer layers of the Sun will expand to roughly 260 times its current diameter, and the Sun will become a red giant. The expanding Sun is expected to vaporize Mercury and Venus and render Earth uninhabitable as the habitable zone moves out to the orbit of Mars. Eventually, the core will be hot enough for helium fusion and the Sun will burn helium for a time, after which nuclear reactions in the core will start to dwindle.
At this point, the Sun’s outer layers will move away into space, leaving a white dwarf – an extraordinarily dense object that will have half the original mass of the Sun, but will be the size of Earth. The ejected outer layers will form what is known as a planetary nebula, returning some of the material that formed the Sun to the interstellar medium.
Inner Solar System:
In the inner Solar System, we find the “Inner Planets” – Mercury, Venus, Earth, and Mars – which are so named because they orbit closest to the Sun. In addition to their proximity, these planets have a number of key differences that set them apart from planets elsewhere in the Solar System.
For starters, the inner planets are rocky and terrestrial, composed mostly of silicates and metals, whereas the outer planets are gas giants. The inner planets are also much more closely spaced than their outer Solar System counterparts. In fact, the radius of the entire region is less than the distance between the orbits of Jupiter and Saturn.
Generally, inner planets are smaller and denser than their counterparts, and have few to no moons or rings circling them. The outer planets, meanwhile, often have dozens of satellites and rings composed of particles of ice and rock.
The terrestrial inner planets are composed largely of refractory minerals such as the silicates, which form their crusts and mantles, and metals such as iron and nickel which form their cores. Three of the four inner planets (Venus, Earth and Mars) have atmospheres substantial enough to generate weather. All of them have impact craters and tectonic surface features as well, such as rift valleys and volcanoes.
Of the inner planets, Mercury is the closest to our Sun and the smallest of the terrestrial planets. Its magnetic field is only about 1% that of Earth’s, and it’s very thin atmosphere means that it is hot during the day (up to 430°C) and freezing at night (as low as -187 °C) because the atmosphere can neither keep heat in or out. It has no moons of its own and is comprised mostly of iron and nickel. Mercury is one of the densest planets in the Solar System.
Venus, which is about the same size as Earth, has a thick toxic atmosphere that traps heat, making it the hottest planet in the Solar System. This atmosphere is composed of 96% carbon dioxide, along with nitrogen and a few other gases. Dense clouds within Venus’ atmosphere are composed of sulphuric acid and other corrosive compounds, with very little water. Much of Venus’ surface is marked with volcanoes and deep canyons – the biggest of which is over 6400 km (4,000 mi) long.
Earth is the third inner planet and the one we know best. Of the four terrestrial planets, Earth is the largest, and the only one that currently has liquid water, which is necessary for life as we know it. Earth’s atmosphere protects the planet from dangerous radiation and helps keep valuable sunlight and warmth in, which is also essential for life to survive.
Like the other terrestrial planets, Earth has a rocky surface with mountains and canyons, and a heavy metal core. Earth’s atmosphere contains water vapor, which helps to moderate daily temperatures. Like Mercury, the Earth has an internal magnetic field. And our Moon, the only one we have, is comprised of a mixture of various rocks and minerals.
Mars, as it appears today, Credit: NASA
Mars is the fourth and final inner planet, and is also known as the “Red Planet” due to the oxidization of iron-rich materials that form the planet’s surface. Mars also has some of the most interesting terrain features of any of the terrestrial planets. These include the largest mountain in the Solar System (Olympus Mons) which rises some 21,229 m (69,649 ft) above the surface, and a giant canyon called Valles Marineris – which is 4000 km (2500 mi) long and reaches depths of up to 7 km (4 mi).
Much of Mars’ surface is very old and filled with craters, but there are geologically newer areas of the planet as well. At the Martian poles are polar ice caps that shrink in size during the Martian spring and summer. Mars is less dense than Earth and has a smaller magnetic field, which is indicative of a solid core, rather than a liquid one.
Mars’ thin atmosphere has led some astronomers to believe that the surface water that once existed there might have actually taken liquid form, but has since evaporated into space. The planet has two small moons called Phobos and Deimos.
Outer Solar System:
The outer planets (sometimes called Jovian planets or gas giants) are huge planets swaddled in gas that have rings and plenty of moons. Despite their size, only two of them are visible without telescopes: Jupiter and Saturn. Uranus and Neptune were the first planets discovered since antiquity, and showed astronomers that the solar system was bigger than previously thought.
The outer planets of our Solar System at approximately relative sizes. From left, Jupiter, Saturn, Uranus and Neptune. Credit: Lunar and Planetary Institute
Jupiter is the largest planet in our Solar System and spins very rapidly (10 Earth hours) relative to its orbit of the sun (12 Earth years). Its thick atmosphere is mostly made up of hydrogen and helium, perhaps surrounding a terrestrial core that is about Earth’s size. The planet has dozens of moons, some faint rings and a Great Red Spot – a raging storm that has happening for the past 400 years at least.
Saturn is best known for its prominent ring system – seven known rings with well-defined divisions and gaps between them. How the rings got there is one subject under investigation. It also has dozens of moons. Its atmosphere is mostly hydrogen and helium, and it also rotates quickly (10.7 Earth hours) relative to its time to circle the Sun (29 Earth years).
Uranus was first discovered by William Herschel in 1781. The planet’s day takes about 17 Earth hours and one orbit around the Sun takes 84 Earth years. Its mass contains water, methane, ammonia, hydrogen and helium surrounding a rocky core. It has dozens of moons and a faint ring system. The only spacecraft to visit this planet was the Voyager 2 spacecraft in 1986.
Neptune is a distant planet that contains water, ammmonia, methane, hydrogen and helium and a possible Earth-sized core. It has more than a dozen moons and six rings. NASA’s Voyager 2 spacecraft also visited this planet and its system by 1989 during its transit of the outer Solar System.
How many moons are there in the Solar System? Image credit: NASA
Trans-Neptunian Region:
There have been more than a thousand objects discovered in the Kuiper Belt, and it’s theorized that there are as many as 100,000 objects larger than 100 km in diameter. Given to their small size and extreme distance from Earth, the chemical makeup of KBOs is very difficult to determine.
However, spectrographic studies conducted of the region since its discovery have generally indicated that its members are primarily composed of ices: a mixture of light hydrocarbons (such as methane), ammonia, and water ice – a composition they share with comets. Initial studies also confirmed a broad range of colors among KBOs, ranging from neutral grey to deep red.
This suggests that their surfaces are composed of a wide range of compounds, from dirty ices to hydrocarbons. In 1996, Robert H. Brown et al. obtained spectroscopic data on the KBO 1993 SC, revealing its surface composition to be markedly similar to that of Pluto (as well as Neptune’s moon Triton) in that it possessed large amounts of methane ice.
Water ice has been detected in several KBOs, including 1996 TO66, 38628 Huya and 20000 Varuna. In 2004, Mike Brown et al. determined the existence of crystalline water ice and ammonia hydrate on one of the largest known KBOs, 50000 Quaoar. Both of these substances would have been destroyed over the age of the Solar System, suggesting that Quaoar had been recently resurfaced, either by internal tectonic activity or by meteorite impacts.
Keeping Pluto company out in the Kuiper belt are many other objects worthy of mention. Quaoar, Makemake, Haumea, Orcus and Eris are all large icy bodies in the Belt and several of them even have moons of their own. These are all tremendously far away, and yet, very much within reach.
Oort Cloud and Farthest Regions:
The Oort Cloud is thought to extend from between 2,000 and 5,000 AU (0.03 and 0.08 ly) to as far as 50,000 AU (0.79 ly) from the Sun, though some estimates place the outer edge as far as 100,000 and 200,000 AU (1.58 and 3.16 ly). The Cloud is thought to be comprised of two regions – a spherical outer Oort Cloud of 20,000 – 50,000 AU (0.32 – 0.79 ly), and disc-shaped inner Oort (or Hills) Cloud of 2,000 – 20,000 AU (0.03 – 0.32 ly).
The outer Oort cloud may have trillions of objects larger than 1 km (0.62 mi), and billions that measure 20 kilometers (12 mi) in diameter. Its total mass is not known, but – assuming that Halley’s Comet is a typical representation of outer Oort Cloud objects – it has the combined mass of roughly 3×1025 kilograms (6.6×1025 pounds), or five Earths.
The layout of the solar system, including the Oort Cloud, on a logarithmic scale. Credit: NASA
Based on the analyses of past comets, the vast majority of Oort Cloud objects are composed of icy volatiles – such as water, methane, ethane, carbon monoxide, hydrogen cyanide, and ammonia. The appearance of asteroids thought to be originating from the Oort Cloud has also prompted theoretical research that suggests that the population consists of 1-2% asteroids.
Earlier estimates placed its mass up to 380 Earth masses, but improved knowledge of the size distribution of long-period comets has led to lower estimates. The mass of the inner Oort Cloud, meanwhile, has yet to be characterized. The contents of both Kuiper Belt and the Oort Cloud are known as Trans-Neptunian Objects (TNOs), because the objects of both regions have orbits that that are further from the Sun than Neptune’s orbit.
Exploration:
Our knowledge of the Solar System also benefited immensely from the advent of robotic spacecraft, satellites, and robotic landers. Beginning in the mid-20th century, in what was known as “The Space Age“, manned and robotic spacecraft began exploring planets, asteroids and comets in the Inner and Outer Solar System.
All planets in the Solar System have now been visited to varying degrees by spacecraft launched from Earth. Through these unmanned missions, humans have been able to get close-up photographs of all the planets. In the case of landers and rovers, tests have been performed on the soils and atmospheres of some.
Photograph of a Russian technician putting the finishing touches on Sputnik 1, humanity’s first artificial satellite. Credit: NASA/Asif A. Siddiqi
The first artificial object sent into space was the Soviet satellite Sputnik 1, which was launched in space in 1957, successfully orbited the Earth for months, and collected information on the density of the upper atmosphere and the ionosphere. The American probe Explorer 6, launched in 1959, was the first satellite to capture images of the Earth from space.
Robotic spacecraft conducting flybys also revealed considerable information about the planet’s atmospheres, geological and surface features. The first successful probe to fly by another planet was the Soviet Luna 1 probe, which sped past the Moon in 1959. The Mariner program resulted in multiple successful planetary flybys, consisting of the Mariner 2 mission past Venus in 1962, the Mariner 4 mission past Mars in 1965, and the Mariner 10 mission past Mercury in 1974.
By the 1970’s, probes were being dispatched to the outer planets as well, beginning with the Pioneer 10 mission which flew past Jupiter in 1973 and the Pioneer 11 visit to Saturn in 1979.The Voyager probes performed a grand tour of the outer planets following their launch in 1977, with both probes passing Jupiter in 1979 and Saturn in 1980-1981. Voyager 2 then went on to make close approaches to Uranus in 1986 and Neptune in 1989.
Launched on January 19th, 2006, the New Horizons probe is the first man-made spacecraft to explore the Kuiper Belt. This unmanned mission flew by Pluto in July 2015. Should it prove feasible, the mission will also be extended to observe a number of other Kuiper Belt Objects (KBOs) in the coming years.
Orbiters, rovers, and landers began being deployed to other planets in the Solar System by the 1960’s. The first was the Soviet Luna 10 satellite, which was sent into lunar orbit in 1966. This was followed in 1971 with the deployment of the Mariner 9 space probe, which orbited Mars, and the Soviet Venera 9 which orbited Venus in 1975.
The Galileo probe became the first artificial satellite to orbit an outer planet when it reached Jupiter in 1995, followed by the Cassini–Huygens probe orbiting Saturn in 2004. Mercury and Vesta were explored by 2011 by the MESSENGER and Dawn probes, respectively, with Dawn establishing orbit around the asteroid/dwarf planet Ceres in 2015.
The first probe to land on another Solar System body was the Soviet Luna 2 probe, which impacted the Moon in 1959. Since then, probes have landed on or impacted on the surfaces of Venus in 1966 (Venera 3), Mars in 1971 (Mars 3 and Viking 1 in 1976), the asteroid 433 Eros in 2001 (NEAR Shoemaker), and Saturn’s moon Titan (Huygens) and the comet Tempel 1 (Deep Impact) in 2005.
Curiosity Rover self portrait mosaic, taken with the MAHLI camera while sitting on flat sedimentary rocks at the “John Klein” outcrop in Feb. 2013. Credit: NASA/JPL-Caltech/MSSS/Marco Di Lorenzo/KenKremer
To date, only two worlds in the Solar System, the Moon and Mars, have been visited by mobile rovers. The first robotic rover to land on another planet was the Soviet Lunokhod 1, which landed on the Moon in 1970. The first to visit another planet was Sojourner, which traveled 500 meters across the surface of Mars in 1997, followed by Spirit(2004), Opportunity (2004), and Curiosity (2012).
Manned missions into space began in earnest in the 1950’s, and was a major focal point for both the United States and Soviet Union during the “Space Race“. For the Soviets, this took the form of the Vostok program, which involved sending manned space capsules into orbit.
The first mission – Vostok 1 – took place on April 12th, 1961, and was piloted by Soviet cosmonaut Yuri Gagarin (the first human being to go into space). On June 6th, 1963, the Soviets also sent the first woman – Valentina Tereshvoka – into space as part of the Vostok 6 mission.
In the US, Project Mercury was initiated with the same goal of placing a crewed capsule into orbit. On May 5th, 1961, astronaut Alan Shepard went into space aboard the Freedom 7mission and became the first American (and second human) to go into space.
After the Vostok and Mercury programs were completed, the focus of both nations and space programs shifted towards the development of two and three-person spacecraft, as well as the development of long-duration spaceflights and extra-vehicular activity (EVA).
Bootprint in the moon dust from Apollo 11. Credit: NASA
This took the form of the Voshkod and Gemini programs in the Soviet Union and US, respectively. For the Soviets, this involved developing a two to three-person capsule, whereas the Gemini program focused on developing the support and expertise needed for an eventual manned mission to the Moon.
These latter efforts culminated on July 21st, 1969 with the Apollo 11 mission, when astronauts Neil Armstrong and Buzz Aldrin became the first men to walk on the Moon. As part of the Apollo program, five more Moon landings would take place through 1972, and the program itself resulted in many scientific packages being deployed on the Lunar surface, and samples of moon rocks being returned to Earth.
After the Moon Landing took place, the focus of the US and Soviet space programs then began to shift to the development of space stations and reusable spacecraft. For the Soviets, this resulted in the first crewed orbital space stations dedicated to scientific research and military reconnaissance – known as the Salyut and Almaz space stations.
The first orbital space station to host more than one crew was NASA’s Skylab, which successfully held three crews from 1973 to 1974. The first true human settlement in space was the Soviet space station Mir, which was continuously occupied for close to ten years, from 1989 to 1999. It was decommissioned in 2001, and its successor, the International Space Station, has maintained a continuous human presence in space since then.
Space Shuttle Columbia launching on its maiden voyage on April 12th, 1981. Credit: NASA
The United States’ Space Shuttle, which debuted in 1981, became the only reusable spacecraft to successfully make multiple orbital flights. The five shuttles that were built (Atlantis, Endeavour, Discovery, Challenger, Columbiaand Enterprise) flew a total of 121 missions before being decommissioned in 2011.
During their history of service, two of the craft were destroyed in accidents. These included the Space Shuttle Challenger – which exploded upon take-off on Jan. 28th, 1986 – and the Space Shuttle Columbia which disintegrated during re-entry on Feb. 1st, 2003.
In 2004, then-U.S. President George W. Bush announced the Vision for Space Exploration, which called for a replacement for the aging Shuttle, a return to the Moon and, ultimately, a manned mission to Mars. These goals have since been maintained by the Obama administration, and now include plans for an Asteroid Redirect mission, where a robotic craft will tow an asteroid closer to Earth so a manned mission can be mounted to it.
All the information gained from manned and robotic missions about the geological phenomena of other planets – such as mountains and craters – as well as their seasonal, meteorological phenomena (i.e. clouds, dust storms and ice caps) have led to the realization that other planets experience much the same phenomena as Earth. In addition, it has also helped scientists to learn much about the history of the Solar System and its formation.
As our exploration of the Inner and Outer Solar System has improved and expanded, our conventions for categorizing planets has also changed. Our current model of the Solar System includes eight planets (four terrestrial, four gas giants), four dwarf planets, and a growing number of Trans-Neptunian Objects that have yet to be designated. It also contains and is surrounded by countless asteroids and planetesimals.
Given its sheer size, composition and complexity, researching our Solar System in full detail would take an entire lifetime. Obviously, no one has that kind of time to dedicate to the topic, so we have decided to compile the many articles we have about it here on Universe Today in one simple page of links for your convenience.
There are thousands of facts about the solar system in the links below. Enjoy your research.
We know that in space, no one can hear you scream. But what would things sound like on another planet?
When humans finally set foot on Mars, they’re going to be curious about everything around them.
What’s under that rock? What does it feel like to jump in the lower Martian gravity. What does Martian regolith taste like? What’s the bitcoin to red rock exchange rate?
As long as they perform their activities in the safety of a pressurized habitation module or exosuit, everything should be fine. But what does Mars sound like?
I urge all future Martian travelers, no matter how badly you want to know the answer to this question: don’t take your helmet off. With only 1% the atmospheric pressure of Earth, you’d empty your lungs with a final scream in a brief and foolish moment, then suffocate horribly with a mouthful of dust on the surface of the Red Planet.
But… actually, even the screaming would sound a little different. How different? Let me show you. First you just need to take your helmet off for a just a little sec, just an itsy bitsy second. Here, I’ll hold it for you. Oh, come on, just take your helmet off. All the cool kids are doing it.
What about Venus? Or Titan? What would everything sound like on an alien world?
We evolved to exist on Earth, and so it’s perfectly safe for us to listen to sounds in the air. No space suit needed. Unless you didn’t evolve on Earth, in which case I offer to serve as emissary to our all new alien overlords.
You know sounds travel when waves of energy propagate through a medium, like air or water. The molecules bump into each other and pass along the energy until they strike something that won’t move, like your ear drum. Then your brain turns bouncing into sounds.
The speed of the waves depends on what the medium is made of and how dense it is. For example, sound travels at about 340 meters/second in dry air, at sea level at room temperature. Sound moves much more quickly through liquid. In water it’s nearly 1,500 m/s. It’s even faster through a solid – iron is up past 5,100 m/s. Our brain perceives a different sound depending on the intensity of the waves and how quickly they bounce off our ears.
Artist’s impression of the surface of Venus. Credit: ESA/AOES
Other worlds have media that sound waves can travel through, and with your eardrum exposed to the atmosphere you should theoretically hear sounds on other worlds. Catastrophic biological failures from using your eardrums outside of documented pressure tolerances notwithstanding.
Professor Tim Leighton and a team of researchers from the University of Southampton have simulated what we would hear standing on the surface of other worlds, like Mars, Venus or even Saturn’s Moon Titan.
On Venus, the pitch of your voice would become deeper, because vocal cords would vibrate much more slowly in the thicker Venusian atmosphere. But sounds would travel more quickly through the soupy atmosphere. According to Dr. Leighton, humans would sound like bass Smurfs. Mars would sound a little bit higher, and Titan would sound totally alien.
Dr. Leighton actually simulated the same sound on different worlds. Here’s the sound of thunder on Earth.
Here’s what it would sound like on Venus.
And here’s what it would sound like on Mars.
Here’s what a probe splashing into water on Earth would sound like.
And here’s what it would sound like splashing into a hydrocarbon lake on Titan.
You might be amazed to learn that we still haven’t actually recorded sounds on another world, right up until someone points out that putting a microphone on another planet hasn’t been that big a priority for any space mission.
A fish-eye view of Titan’s surface from the European Space Agency’s Huygens lander in January 2005. Credit: ESA/NASA/JPL/University of Arizona
Especially when we could analyze soil samples, but hey fart sounds played and then recorded in the Venusian atmosphere could prove incredibly valuable to the future of internet soundboards.
The Planetary Society has been working to get a microphone included on a mission. They actually included a microphone on the Mars Polar Lander mission that failed in 1999. Another French mission was going to have a microphone, but it was cancelled. There are no microphones on either Spirit or Opportunity, and the Curiosity Rover doesn’t have one either despite its totally bumping stereo.
Here’s is the only thing we’ve got. When NASA’s Phoenix Lander reached the Red Planet in 2008, it had a microphone on board to capture sounds. It recorded audio as it entered the atmosphere, but operators turned the instrument off before it reached the surface because they were worried it would interfere with the landing.
Meh. I’m going to need you to do better NASA. I want an actual microphone recording winds on the surface of Mars. I hope it’s something Dethklok puts on their next album, they could afford that kind of expense.
It turns out, that if you travel to an alien world, not only would the sights be different, but the sounds would be alien too. Of course, you’d never know because you’re be too chicken to take your helmet off and take in the sounds through the superheated carbon dioxide or methane atmosphere.
What sounds would you like to hear on an alien world? Tell us in the comments below.
Just how dangerous are the terrifying dust storms that swarm Mars?
Brave explorers trek across the red dunes of Mars when a dangerous dust storm blows in. In moments, our astronauts are blasted by gale force winds and driving sand, reducing visibility to zero. The brave heroes stumble desperately through the driving onslaught, searching in vain for shelter from the catastrophic conditions. One is blown into a ravine, or right to the edge of the cliff, requiring a dramatic rescue and likely a terrible terrible sacrifice and important parting words showing the true mettle of our heroes.
“Tell my Asuka… printed body pillow… I loved her…”
Will they make it? Why the heck would anyone land on that dusty irradiated death trap? Actually, a better question might be “Why do writers lean so hard on this trope?”. I’m looking at you Andy Weir.
Martian dust storms don’t just come from the fevered imagination of the same sci-fi writer who gave us a lush Venusian jungle, Saturnalian lava flats and Moon floor cheese. These dust storms are all too real and they drive at serious windspeeds.
NASA’s Viking landers clocked them at 100 km/h during dust storm season. Which is a thing on Mars. The landers sheltered enough from the big storms that they probably didn’t experience the greatest winds they’re capable of.
Scientists have seen evidence that sand is shifted around on the surface of Mars, and the regolith requires high wind speeds to pick it up and shove it around. Dust devils spin up across the surface, and rotate at hurricane speeds.
When the wind is above 65 km/h, it’s fast enough to pick up dust particles and carry them into the atmosphere encasing the planet in a huge, swirling, shroud. Freaked out yet? Is this dangerous? It sure sounds dangerous.
Apologies to all the fearmongering sci-fi writers, but actually, it’s not that dangerous. Here’s why.
First off, you’re not on Mars. It’s a book. Second, it’s a totally different experience on Earth. Here when you feel the wind blasting you in the face, or watch it dismantle a house during a tornado, it’s the momentum of the air particles hammering into it.
An illustration of a dust storm on Mars. Credit: Brian Grimm and Nilton Renno
That momentum comes from air particle density and their velocity. Sadly, the density of the atmosphere on Mars is a delicate 1% of what we’re used to. It’s got the velocity, but it just doesn’t have the density.
It’s the difference between getting hit by a garden hose and a firehose with the same nozzle speed. One would gets you soaked, the other can push you down the street and give you bruises.
To feel a slight breeze on Mars similar to Earth, you multiply the wind speed by 10. So, if the wind was going about 15 km/h here, you’d need to be hit by winds going about 150 km/h there to have the same experience.
It’s not impossible for winds to go that fast on Mars, but that’s still not enough wind to fly a kite. To get it off the ground your mission buddy holds the kite, and you run around in the dumb Martian sand like a try-hard ass.
It would fly for a second and then crash down. You’d wonder why you even brought a kite to Mars in the first place because it’s NEVER windy enough.
Boo hoo. Your Mars kite doesn’t work. Good news! You’re on Mars!
Bad news. It was a one way trip. Good news! A wizard has made you immortal!
Bad news. The wizard has brought to life the entire fictional cast of the Twilight series and they’re also there and immortal. Have fun brooding with your new dorky friends, FOR ETERNITY.
What I’m saying is you could stand on the red planet restaurant patio and laugh at anything the weather system could throw at you. That is unless, you’re solar powered.
Opportunity Rover. Credit: NASA
Mars gets regular dust storms. From time to time, they can get truly global. In 2001, a storm picked up enough dust to shroud the entire planet in a red haze. Temperatures went up as dust helped trap heat in the atmosphere. This storm lasted for 3 months before temperatures cooled, and the dust settled back down again.
During a storm in 2007, dust blocked 99% of the light reaching the solar panels of the Opportunity rover. This severely decreased the energy it had to power its instruments, and most importantly, the heaters. Ultimately, it was possible that the cold could kill the rover, if the dust hadn’t subsided quickly enough.
If you happen to see a movie or read a book about an astronaut on Mars dealing with a dangerous dust storm, don’t worry. They’ll be fine, the wind won’t shred them to pieces. Instead, focus on unbreathably thin atmosphere, the bone chilling cold, or the constant deadly radiation.
That and where’s their food come from again? Well, now you know dust storms aren’t a big issue. Want to travel to Mars? Tell us in the comments below.
If you haven’t checked it out yet, go read “The Martian”. Jay and I loved the pants off it and we can’t wait to see the film version.
