Cassini, MESSENGER, and MOM: A Space Probe Odyssey

Cassini_Saturn_Orbit_InsertionIt had has been a big month in the field of space probes and satellites. Whether they are in orbit around Mercury, on their way to Mars, or floating in the outer Solar System, there’s been no shortage of news and inspirational footage to be had. And it is a testament to the age we live in, where space news is accessible and can instantly be shared with millions of people around the world.

First up, there’s the recent release of Cassini’s magnificent image of Saturn’s rings shining in all their glory. Back in July, Cassini got a good look back at Earth from about 1.5 billion kilometers (932 million miles) away. Known as
“The Day The Earth Smiled”, NASA has spent the past few months cobbling together this picture from numerous shots taken during Cassini’s circuitous orbit around Saturn.

cassini-jupiter-annotatedCassini has always been able to take impressive pictures in Earth’s general direction, but this picture was special since it used the enormous bulk of Saturn to block the usually confounding brightness of the Sun. Cassini, which was launched to survey the outer planets in 1997, captured an absolutely incredible image of both the Earth as a pale blue dot, and of Saturn as a striking, luminous apparition.

As part of NASA’s latest awareness campaign, which tried to get everyday citizens to smile at the sky for the first posed interplanetary photo most of us have ever experienced, the photo captured the halo effect that makes our sixth planet look truly breathtaking. In the annotated version (pictured above), you can also see Venus, Mars, and some of Saturn’s moons.


Next up, there’s the MESSENGER probe, which managed to capture these impressive new videos of Mercury’s surface. As part of the NASA Advisory Council (NAC) ride-along imaging campaign, these videos were captured using the Mercury Dual Imaging System (MDIS). Even though the original high-res images were captured four seconds apart, these videos have been sped up to a rate of 15 images per second.


The views in each video are around 144-178 km (90-110 miles) across. The large crater visible in the beginning of the second video is the 191-km (118-mile) wide Schubert basin. In related news, there are new maps of Mercury available on the US Geological Survey website! Thanks to MESSENGER we now have the entirety of the first planet from the Sun imaged and mapped.

MESSENGER launched from Cape Canaveral Air Force Station back in August of 2004 and established orbit around Mercury on March 18th, 2011. It was the first man-made spacecraft ever to do so, and has provided the most comprehensive mapping of Mercury to date, not to mention evidence of ice, organic molecules, and detailed conditions on the surface.

India_Mars_Orbiter1And last, but not least, there was the recent launch of the Indian Space Research Organization’s (ISRO) new Mars Orbiter Mission (aka. MOM). The launch took place on Tuesday, November 5th from the Indian space port located on a small island in the Bay of Bengal. As the nation’s first attempt to reach the Red Planet, the aim of the $70 million mission goes beyond mere research.

In addition to gathering information that might indicate if life has ever existed or could exist on Mars, the mission is also meant to showcase India’s growing prowess in the field of space and to jump ahead of its regional rival (China) in the big interplanetary march. As Pallava Bagla, one of India’s best known science commentators, put it:

In the last century the space race meant the US against the Soviets. In the 21st century it means India against China. There is a lot of national pride involved in this.

India Mars probeIn addition, there has been quite a bit of speculation that the missionw as designed to stimulate national pride in the midst of an ongoing economic crisis. In recent years, a plunging currency, ailing economy and the state’s seeming inability to deliver basic services have led many Indians to question whether their nation is quite as close to becoming a global superpower as it seemed in the last decade.

MOM is expected to arrive in the vicinity of Mars on September 24th, 2014 where it will assume an elliptical orbit around the planet and begin conducting atmospheric surveys. If all continues to goes well, India will the elite club of only four nations that have launched probes which successfully investigated the Red Planet from orbit or the surface – following the Soviet Union, the United States and the European Space Agency (ESA).

India_Mars_Orbiter2MOM was also the first of two new Mars orbiter science probes that left Earth and began heading for Mars this November. The second was NASA’s $671 million MAVEN orbiter, which launched on November 18th atop an Atlas V rocket from Cape Canaveral in Florida. MAVEN is slated to arrive just two days before MOM, and research efforts will be coordinated between the two agencies.

Much like MAVEN, MOM’s goal is to study the Martian atmosphere , unlock the mysteries of its current state and determine how, why and when the atmosphere and liquid water were lost – and how this transformed Mars climate into its cold, desiccated state it is in today. In addition to aiding our scientific understanding of the world, it may help us to transform the planet into a liveable environment once again.

For many people, these developments are an indication of things to come. If humanity ever intends to become an interplanetary species, an expanding knowledge of our Solar System is an absolute prerequisite. And in many respects, making other planets our home may be the only way we can survive as a species, given our current rate of population growth and consumption.

Sources: extremetech.com, nasa.gov, universetoday.com, planetarynames.wr.usgs.gov, theguardian.com, www.isro.org

News From Space: MAVEN’s “Time-Machine” for Mars

marsYes, the name is a bit of a attention-getter, but when you come to understand the purpose behind Lockheed Martin’s new spacecraft, the description does appear to be quite apt. It’s known as MAVEN, which stands for Mars Atmosphere and Volatile EvolutioN, and it is currently being produced in Lockheed Martin’s Martin Space Systems facility in Denver, Colorado.

People may recall how earlier this year, MAVEN was mentioned as part of the “Going to Mars” campaign. A project that is being organized by the University of Colorado at Boulder’s Laboratory for Atmospheric and Space Physics (CU/LASP), the Martian orbiter will be carrying a DVD featuring the names of everyone who applies, as well as three specially-selected haikus.

However, it is MAVEN’s larger mission which is now the focus of much interest. Later this year, NASA will be launching the orbiter to Mars for the sake of examine the atmosphere and answering some burning questions that remain about the planet. Thanks to evidence provided by Curiosity, Opportunity, and other missions, scientists now know that the Martian surface once boasted conditions suitable for life, including liquid water.

maven_orbitHence, Maven’s ultimate purpose, which will be will to orbit the planet and examine whether the atmosphere could also have provided life support. Scientists working on the Maven mission want to understand what this atmosphere was like, and the processes that led to its destruction. As Guy Beutelschies, Maven Programme Manager at Lockheed Martin, put it:

What we know from our missions looking at the surface of Mars is that there used to be water there. We can see the outlines of ancient rivers, the shorelines of ancient oceans. But water can’t exist there now – the atmosphere is too thin and too dry, any water would just evaporate or freeze. 

So the big question is what happened to Mars’ atmosphere? Short of being able to travel back in time into the Martian past, how would anyone go about tackling these questions with a mission today? Beutelshcies explained it as follows:

[The atmosphere] used to be thicker, warmer, wetter, now it’s thin and dry. How did we get there? In a sense we are building a little bit of a time machine. What we’re doing is understanding the processes.

maven_atmosphereJust last week, evidence provided by the Curiosity rover supports the theory that Mars may have lost most of its atmosphere billions of years ago. Still, scientists remain skeptical that Mars once had an atmosphere comparable to that of Earth. Today, that atmosphere is roughly one-hundredth the thickness of Earth’s, made up mostly of carbon dioxide and a tiny fraction of water vapor. What little remains is being stripped away by the solar wind.

And unlike Earth, Mars does not have a magnetosphere to protect its atmosphere from being blown away – at least not anymore. Such a fragile, thin band around is now unlikely to support any sort of life, as far as we know. But the atmosphere in the past must have been more substantial to allow the formation of rivers, lakes and oceans.

mars_sunsetBruce Jakosky, the Principal Investigator for Maven who is based at the University of Colorado’s CU/LASP lab in Boulder, claims:

We think that Mars used to have a magnetic field. We see places on the surface that retain some remnant magnetism, they were imprinted when they formed with whatever magnetism was there. We think that some four billion years ago, when the magnetic field turned off, that turn-off of the magnetic field allowed [for the] turn-on of the stripping by the solar wind.

To investigate the processes taking place today, Maven will dip into the Martian upper atmosphere with each orbit, measuring the particles, sampling gases, monitoring the magnetic field and solar wind. Whereas the rovers have looked at the atmosphere from the ground up, MAVEN will look at it from the top down. At this point, both are needed to put together a picture of what’s controlling the Mars environment.

maven_atmo1As well as filling in the blanks about Mars’ depleted atmosphere, Maven will also provide clues to the habitability of other planets beyond the solar system. As Jakosky said, the research conducted will have far-reaching implication for our understanding:

In trying to understand the distribution of life throughout the Universe, this is a really important indicator. Understanding the environmental conditions that allow [life] to exist, or don’t allow it to exist, is key to being able to extrapolate elsewhere.

What’s more, understanding what happened to Mars will provide some key insight into the history of our Solar System, and how it went from being a star with two planets that had oceans and atmospheres to just one. Knowing why things continued to operate on Earth, while on Mars they went horribly wrong, is likely to be quite the eye-opener, and make us all thankful we evolved here on Earth.

Source: bbc.com