SMC, ULA Enter into CRADA to Certify Vulcan Launch Vehicle
Today, Elon Musk elaborated on his plans to make humanity a planet-faring species. We've known for a long time that Mars is SpaceX's destination, but the fine details haven't been revealed. In today's talk at the International Astronautical Congress (IAC), Musk revealed a game-changer for travel to Mars, and beyond.
If anyone has ever guessed that Musk's plans involved a refuelling ship, I've never heard them say it out loud. But that's exactly what Musk revealed. SpaceX plans to launch a Mars-bound craft into orbit, then launch a refuelling craft to refill the interplanetary ship's fuel tanks. Only then would the Interplanetary Transport System (ITS) depart for Mars.
SpaceX's proposed system is all about lowering the cost of travel to Mars. Only when the cost is lowered, does a sustained presence there become realistic. And Musk's ITS system will definitely lower the cost.
Traditional space travel would cost 10 billion to get one person to Mars. Musk said that they can get it down to the median cost of a house in the US, about $200,000 US. The idea is that anyone who really wanted to could save up enough money and go to Mars. Musk did acknowledge that it will be tricky to reduce the cost of the Earth to Mars trip by a whopping 5 million percent.
There are four keys to reducing the cost:full reusability refilling in orbit propellant production on Mars right propellant
The ITS would feature reusable boosters, reusable spaceships, and refuelling in orbit. The interplanetary ship would be launched into orbit around Earth and parked there. Fuel ships would make 3 to 5 trips to fill the tank of the interplanetary ship waiting in orbit. From there, Musk thinks that the trip to Mars could take as little as 80 days. In the more distant future, that could be cut to 30 days.
If this whole system isn't shocking enough, and thrilling enough, for you, Musk has more than just one of these craft in mind. He imagines a fleet of them, perhaps 1,000, travelling en masse back and forth to Mars.
The driving force behind all this is, of course, making Mars possible. In his presentation, Musk said we have two paths. One is to stay on Earth and face extinction from some doomsday event. The other is to become an interplanetary species, and use Mars to back up Earth's biosphere. The SpaceX system is designed to make the second path possible.
Musk talked about the need to create a self-sustaining city in its own right. That obviously won't happen right away, but it'll never happen unless transport to Mars, and back, becomes feasible. With the proposed SpaceX system, Mars will be an option. Musk thinks that the ITS could also get us to one of the Jovian moons, if we could create fuel production and depots. In fact, he said we can probably go all the way to Pluto and beyond.
There are a lot of challenges for this system. It's far from a done deal. The system will require newer, more powerful engines. But SpaceX is already working on that. It's called the Raptor, and testing has already begun.
Musk talked about the impressive exploration done on Mars by NASA and other agencies, but stressed that it's time to take things further and aim for a sustained presence on Mars. To that end, SpaceX plans on sending a craft to Mars during every Earth-Mars rendezvous, which happens about every 22 months. Initially, that will be done with an unmanned Dragon capsule.
The mood at Musk's presentation was one of excitement. The crowd was definitely there to see him. There was one humorous moment when Musk remarked "Timelines. I'm not the best at this sort of thing." But really, what agency can adhere to strict schedules when doing something that's never been done before? Especially in the realm of interplanetary travel?
There was much more detail in his presentation, including in the Q&A that followed his talk. Stay tuned for more.
More To Come
The post Ready Or Not, Musk Is Dragging Us Into Interplanetary Species Status appeared first on Universe Today.
Since it first landed on the surface of Mars on August 6th, 2012, the science team behind the Curiosity rover has conducted some crucial experiments. In the course of collecting rock samples, testing the air, and searching for organic molecules, the rover has revealed some very impressive things about Mars' past.
After months of exploring the slopes around Mount Sharp, which sits in the ancient lake basin known as the Gale Crater, the rover team has been drilling into the formation see what's hidden beneath. And with drill samples now obtained from Mount Sharp's lower levels, the Curiosity team hopes to learn a great deal more about the planet's ancient history.
For years, scientists have understood that Mount Sharp is essentially a giant mound of sedimentary deposits that were deposited by water billions of years ago. These sediment layers are believed to have been laid down over the course of 2 billion years, and most likely came into contact with the water that filled the crater 3.3. to 3.8 billion years ago.
As Ashwin Vasavada, the Deputy Project Scientist of the Curiosity mission at JPL, explained to Universe Today via email:
"Aeolis Mons, known informally as Mount Sharp, is the central mountain within Gale crater where Curiosity landed. It was chosen as Curiosity?s landing site because the mountain and the nearby plains have evidence for ancient liquid water in the form of channels and debris fans, as well as minerals that form when liquid water interacts with rock. Furthermore, the layers within lower Mount Sharp change in mineralogy in a way that indicates that they may record the drying out of Mars: lower and older layers indicate more water, while higher and younger layers indicate less."
The drilling began late on Wednesday, Sept. 24th, when Curiosity's hammering drill bore about 6.7 cm (2.6 inches) into Mount Sharp and collected a powdered-rock sample. Data and images of the drill sample were then received on the following morning (Thursday, Sept. 25th) at NASA's Jet Propulsion Laboratory in Pasadena, California.
With drill samples now obtained from the lower level of Mount Sharp, Curiosity will soon deposit them into a scoop in the rover's arm. While there, the rock powder will be examined to see if it is safe and of proper quality to be analyzed by Curiosity's internal laboratory instruments, which will determine its chemical and mineralogical properties.
And once that analysis is complete, the Curiosity team hopes to make some more major discoveries of the region, the ultimate purpose of which is to determine if life could have existed in the Gale Crater during its warmer, wetter past. As Vasavada explained:
"Now that water-rich ancient environments have been discovered and studied on the plains and in the lowest layers of Mount Sharp, the team in drilling additional samples from progressively higher and younger layers to see how the ancient environment changed over time.
"The team also is searching for additional evidence of organic molecules that would help them understand whether the raw ingredients of life were present and how they degrade over time. The degradation is important to understand for the M2020 Mars rover mission that will search for signatures of ancient microbial life."
Since September 11th, 2014, Curiosity has been exploring the slopes of Mount Sharp. As of Sept. 19th, 2016, the rover arrived at a area called "Pahrump Hills," a basalt rock outcropping located in the lower region of Mount Sharp (known as the Murray Formation).
On Sept. 22nd, the rover completed mini-drill test to make sure the rock was suitable for drilling. This took place in an area known as "Confidence Hills", which proved to be soft enough to obtain rock samples. This was the second mini-drill test since last month, the previous one having found that the rock was not stable enough for drilling.
Looking forward, the team plans to drill regularly as the rover climbs higher and higher along Mount Sharp, in the process accessing progressively younger layers of rock. In so doing, they will be able to create a comprehensive picture of how Mars evolved over time to become the dry and cold landscape it is today.
The team will also continue to use the rovers instruments to monitor the modern environment, including the weather and composition of the atmosphere to get a better picture of the planet's meteorology today. Needless to say, this is not the last "taste" Curiosity will get of good ol' Aeolis Mons!
Be sure to check this video too - "A Taste of Mount Sharp" - courtesy of NASA JPL:
Further Reading: NASA
Mercury is a fascinating planet. As our Suns' closest orbiting body, it experiences extremes of heat and cold, has the most eccentric orbit of any Solar planet, and an orbital resonance that makes a single day last as long as two years. But since the arrival of the MESSENGER probe, we have learned some new and interesting things about the planet's geological history as well.
For example, images that were recently obtained by the NASA spacecraft revealed previously undetected landforms - small fault scarps - that appear to be geologically young. The presence of these features have led scientists to conclude that Mercury is still contracting over time, which means that - like Earth - it is tectonically active.
In geology, fault scarps refer to small step-like formations in the surface of a planet, where one side of a fault has moved vertically relative to the other. Previously, scientists believed that Mercury was tectonically dead, and that all major geological activity had taken place in the planet's early history.
This was evidenced by features spotted by the MESSENGER and Mariner 10 probes, both of which found evidence of large wrinkle ridges and fault scarps on the surface. The features were reasoned to be the result of Mercury contacting as it cooled early in its history (i.e. billion of years ago).
This action caused the planet's crust to break, forming cliffs up to a kilometer and a half (about 1 mile) in height and hundreds of kilometers long. However, as the MESSENGER team noted, these small scarps were considerably younger, dating to about 50 million years of age.
They concluded that the scarps would have to be this young in order to survive bombardment by comets and meteoroids, a common occurrence on Mercury. They also noted their resemblance to similar features on the Moon, which also has young scarps that are the result of recent contraction.
The team's findings were reported in a paper titled ?Recent Tectonic Activity on Mercury Revealed by Small Thrust Fault Scarps", which appeared in the October issue of Nature Geoscience.
?The young age of the small scarps means that Mercury joins Earth as a tectonically active planet, with new faults likely forming today as Mercury?s interior continues to cool and the planet contracts.?
The findings were made during the last 18 months of the MESSENGER mission, during which time the probe lowered its altitude to get higher-resolution images of the planet's surface. The findings are also consistent with recent findings about Mercury's global magnetic field, which appears to be powered by the planet's slowly-cooling outer core.
As Jim Green, NASA's Planetary Science Director, said of the discovery:
?This is why we explore. For years, scientists believed that Mercury?s tectonic activity was in the distant past. It?s exciting to consider that this small planet ? not much larger than Earth?s moon ? is active even today.?
All told, these findings have let scientists know that the planet is still alive, in the geological sense. It also means that that there is likely such as thing as Mercury-quakes, something which NASA is sure to follow up on if and when a lander mission (equipped with seismology instruments) is dispatched to the surface of the planet.
Imagine if you will, that you are a human being living in the prehistoric past. You look up at the sky and see the Sun slowly being blocked out, becoming a ominous black sphere that glows around the edges. Could you really be faulted for thinking that this was some sort of supernatural event, or that the end of the world was nigh?
Of course not. Which is why for thousands of years, human beings believed that solar eclipses were just that - a sign of death or a bad omen. But in fact, an eclipse is merely what happens when one stellar object passes in front of another and obscures it. In astronomy, this happens all the time; and between the Sun, the Moon, and the Earth, total eclipses have been witnessed countless times throughout history.Definition:
The general term for when one body passes in front of another in a solar system is transit. This term accurately describes how, depending on your vantage point, stellar bodies pass in front of each other on a regular basis, thus causing the reflected light from that body to be temporarily obscured.
However, when we are talking about how the Moon can pass between the Earth and the Sun, and how the Earth can pass in front of the Moon, we use the term eclipse. This is also known as a syzygy, an astronomical term derived from ancient Greek (meaning "yoked together") that describes a straight-line configuration between three celestial bodies.Total Solar Eclipse:
When the Moon passes between the Sun and the Earth, and the Moon fully occults (blocks) the Sun, it is known as the solar eclipse. The type of solar eclipse event - total or partial - depends on the distance of the Moon from the Earth during the event.
During an eclipse of the Sun, only a thin path on the surface of the Earth is actually able to experience a total eclipse - this is called the path of totality. People on either side of that path see a partial eclipse, where the Sun is only partly obscured by the Moon, relative to those who are standing in the center and witnessing the maximum point of eclipse.
A total solar eclipse occurs when the Earth intersects the umbra portion - the innermost darkest part - of the Moon's shadow. These are relatively brief events, generally lasting only a few minutes, and can only be viewed along a relatively narrow track (up to 250 km wide). The region where a partial eclipse can be observed is much larger.
During a solar eclipse, the Moon can sometimes perfectly cover the Sun because its size is nearly the same as the Sun's when viewed from the Earth. This, of course, is an illusion brought on by the fact that the Moon is much closer to us than the Sun.
And since it is closer, it can block the light from the Sun and cast a shadow on the surface of the Earth. If you're standing within that shadow, the Sun and the Moon appear to line up perfectly, so that the Moon is completely darkened.
At that point, when the Sun is completely blocked by the Moon, you are witnessing what astronomers call a total solar eclipse - the point of maximum eclipse. After that, the Moon continues to move past the Sun, obscuring smaller and smaller portions of it and allowing more and more light to pass.Total Lunar Eclipse:
A total eclipse of the Moon is a different story. In this situation, the entire Moon passes into the Earth's shadow, darkening it fully. A partial lunar eclipse occurs when the shadow of the Earth doesn't fully cover the Moon, so only part of the Moon is darkened.
Unlike a solar eclipse, a lunar eclipse can be observed from nearly an entire hemisphere. In other words, observers all across planet Earth can see this darkening and it appears the same to all. For this reason it is much more common to observe a lunar eclipse from a given location. A lunar eclipse also lasts longer, taking several hours to complete, with totality itself usually averaging anywhere from about 30 minutes to over an hour.
There are three types of lunar eclipses. There's a penumbral eclipse, when the Moon crosses only the Earth's penumbra (the region in which only a portion of light is obscured); followed by a partial, when the Moon crosses partially into the Earth's umbra (the innermost and darkest part of a shadow, where the light is completely blocked).
Last, there is a total eclipse, when the Moon crosses entirely into the Earth's umbra. A total lunar eclipse involes the Moon passing through all three phases, then gradually admitting light again. Even during a total lunar eclipse, however, the Moon is not completely dark.
Sunlight is still refracted through the Earth's atmosphere and enters the umbra to provide faint illumination. Much as in a sunset, the atmosphere scatters shorter wavelength light, causing it to take on a red hue. This is where the phrase 'Blood Moon' comes from.
Since the Moon orbits the Earth, you would expect to see an eclipse of the Sun once a lunar month, and an eclipse of the Moon once a lunar month. However, this does not happen simply because the Moon's orbit isn't lined up with the Sun. In fact, the Moon's orbit is tilted by a few degrees - 1.543º between the angle of the ecliptic and the lunar equator, to be exact.
This means that three objects only have the opportunity to line up and cause an eclipse a few times a year. It's possible for a total of 7 solar and lunar eclipses every year, but that only happens a few times every century.Other Types of Eclipses:
The term eclipse is most often used to describe either a solar eclipse or a lunar eclipse. However, it can also refer to such events beyond the Earth?Moon system: for example, a planet moving into the shadow cast by one of its moons, a moon passing into the shadow cast by its host planet, or a moon passing into the shadow of another moon.
For instance, during the Apollo 12 mission in 1969, the crew were able to observed the Sun being eclipsed by the Sun. In 2006, during its mission to study Saturn, the Cassini spacecraft was able to capture the image below, which shows the gas giant transiting between it and the Sun.
In July of 2015, when the New Horizons mission passed through the shadow of Pluto, it was able to capture a stunning image of the dwarf planet eclipsing the Sun. The image was taken at a distance of about 2 million km (1.25 million miles) which provided the necessary vantage point to fully obscure the disc of the Sun.
On top of that, many other bodies in the Solar System can experience eclipses as well. These include the four gas giants, all of which have major moons that periodically occult the planet, from the point of view of Earth-based observers.
The most impressive and common of these involve Jupiter and its four largest moons (Io, Europa, Ganymede and Callisto). Given the size and low axial tilt of these moons, they often experience eclipses with Jupiter as a result of transiting relative to our observing instruments.
A well-known example occurred in April of 2014, when the Hubble Space Telescope caught an image of Ganymede passing in front atof Jupiter. At the time the image was taken, Ganymede was casting its shadow within Jupiter's Great Red Spot, which lent the planet a cyclops-like appearance (see below).
The other three gas giants are known to experiences eclipses as well. However, these only occur at certain periods the planet's orbit of the Sun, due to their higher inclination between the orbits of their moons and the orbital plane of the planets. For instance, Saturn's largest moon Titan has been known to only occult the ringed gas giant once about every 15 years.
Pluto has also been known to experience eclipses with is largest moon (and co-orbiting body) Charon. However, in all of these cases, the eclipses are never total, as they do not have the size to obscure the much larger gas giant. Instead, the passage of the moons in front of the larger celestial bodies either cast small shadows on the cloud tops of the gas giants, or leads to an annular eclipse at most.
Similarly, on Mars, only partial solar eclipses are ever possible. This is because Phobos or Deimos are large enough (or distant enough in their orbits) to cover the Sun's disc, as seen from the surface of the planet. Phobos and Deimos have also been known to experience lunar eclipses as they slip into the shadow of Mars.
Martian eclipses have been photographed numerous times from both the surface and from orbit. For example, in 2010, the Spirit rover captured images of a Martian lunar eclipse as Phobos, the larger of the two martian moons, was photographed while slipping into the shadow of Mars.
Also, between Nov. 4 and Nov. 5, 2010, the Opportunity rover captured several images (later turned into two movies) of a Martian sunset. In the course of imaging the Sun for a total of 17 minutes, Opportunity captured still of the Sun experiencing a Solar eclipse. On September 13th, 2012 - during the 37th day of its mission (Sol 27) - the Curiosity rover captured an image of Phobos transiting the Sun.
As far as astronomical events go, total eclipses (Lunar and Solar) are not uncommon occurrences. If you ever want to witness a one, all you need to do is keep track of when one will be visible from your part of the world. A good resource for this is NASA's Eclipse Website and timeanddate.com.
Or, if you're the really adventurous type, you can find out where on Earth the next path of totality is going to be, and then book a vacation to go there. Get to the right spot at the right time, and you should be getting the view of a lifetime.
We have written many articles about the eclipse for Universe Today. Here's a list of articles about specific times when a total Lunar Eclipse took place, and here's a list of Solar Eclipse articles. And be sure to check out this article and video of an Annular Eclipse.
We've also recorded related episodes of Astronomy Cast about Eclipses. Listen here, Episode 160: Eclipses.
Sources:NASA - Eclipse Wikipedia - Eclipse ESA - What is an Eclipse? Time and Date - What are Solar Eclipses?