Host: Fraser Cain (@fcain)
Morgan Rehnberg (cosmicchatter.org / @cosmic_chatter)
Ramin Skibba (@raminskibba)
Alessondra Springmann (@sondy)
Continue reading “Weekly Space Hangout – Dec. 19, 2014: Methane on Mars!”
A United Launch Alliance Altas V 401 rocket like that shown here will launch the next Orbital Sciences Cygnus cargo ship to the space station in place of the Antares rocket. NASA’s Mars-bound MAVEN spacecraft launches atop Atlas V booster at 1:28 p.m. EST from Space Launch Complex 41 at Cape Canaveral Air Force Station on Nov. 18, 2013. Image taken from the roof of the Vehicle Assembly Building (VAB) at NASA’s Kennedy Space Center. Credit: Ken Kremer/kenkremer.com
More photos added[/caption]
Following the catastrophic Oct. 28 failure of an Orbital Sciences Corporation Antares rocket on a critical resupply mission to the space station for NASA, the company is seeking to quickly make up the loss to NASA by announcing the selection of the venerable Atlas V rocket built by United Launch Alliance to launch Orbital’s next Cygnus cargo ship to the orbital science lab.
Orbital and ULA signed a contract to launch at least one, and up to two, Cygnus cargo missions to the International Space Station (ISS) under NASA’s Commercial Resupply Services (CRS) program.
The first Cygnus mission would liftoff sometime late in the fourth quarter of 2015 aboard an Atlas V 401 vehicle from Space Launch Complex 41 (SLC-41) at Cape Canaveral Air Force Station in Florida.
Given that ULA’s full launch manifest was fairly full for the next 18 months, Orbital is fortunate to have arranged one or two available launch slots so quickly in the wake of the Antares launch disaster.
“Orbital is pleased to partner with ULA for these important cargo missions to the International Space Station,” said Frank Culbertson, Orbital executive vice president and general manager of its Advanced Programs Group.
“ULA’s ability to integrate and launch missions on relatively short notice demonstrates ULA’s manifest flexibility and responsiveness to customer launch needs.”
Orbital also stated that there will be “no cost increase to the space agency” by utilizing the Atlas V as an interim launcher.
If necessary, a second Cygnus would be launched by the Atlas V in 2016.
The 401 version of the Atlas uses a 4 meter diameter payload fairing, no solid rocket boosters strapped on to the first stage, and a single-engine Centaur upper stage.
Orbital had been evaluating at least three different potential launch providers.
Observers speculated that in addition to ULA, the other possibilities included a SpaceX Falcon 9 or a rocket from the European Space Agency at the Guiana Space Center.
“We could not be more honored that Orbital selected ULA to launch its Cygnus spacecraft,” said Jim Sponnick, vice president, Atlas and Delta Programs.
“This mission was awarded in a highly competitive environment, and we look forward to continuing ULA’s long history of providing reliable, cost-effective launch services for customers.”
The Orbital-3, or Orb-3, mission that ended in disaster on Oct. 28 was to be the third of eight cargo resupply missions to the ISS through 2016 under the NASA Commercial Resupply Services (CRS) contract award valued at $1.9 Billion.
The highly anticipated launch of the Antares rocket on Oct 28 suddenly went awry when one of the Soviet-era first stage engines unexpectedly exploded and cascaded into a spectacular aerial fireball just above the launch pad at NASA’s Wallops Flight Facility on the Orb-3 mission to the ISS.
Read my earlier eyewitness accounts at Universe Today.
Orbital was awarded a $1.9 Billion contract with NASA under the CRS program to deliver 20,000 kilograms of research experiments, crew provisions, spare parts, and hardware for the eight ISS flights.
In choosing the Atlas V with a greater lift capacity compared to Antares, Orbital will also be able to significantly increase the cargo mass loaded inside the Cygnus by about 35%.
This may allow Orbital to meet its overall space station payload obligation to NASA in 7 total flights vs. the originally planned 8.
The venerable Atlas V rocket is one of the most reliable and well built rockets in the world.
Indeed the Atlas V has been entrusted to launch many high value missions for NASA and the Defense Department – such as MAVEN, Curiosity, JUNO, TDRSS, and the X-37 B.
MAVEN launched on a similar 401 configuration being planned for Cygnus.
The two-stage Atlas rocket is also being man-rated right now to launch humans to low Earth orbit in the near future.
Orbital is still in the process of deciding on a new first stage propulsion system for Antares’ return to flight planned for perhaps sometime in 2016.
Watch here for Ken’s ongoing reporting about Antares and NASA Wallops.
Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.
Feeling lucky? Events such as the Comet Siding Spring approach by Mars in October only happen about once every eight million years, according to NASA.
And after we were treated to spectacular views from the agency’s spacecraft (see Curiosity and Opportunity and MAVEN, for example), we now have fresh pictures this month from an Indian mission. Also, NASA has released science results suggesting that the chemistry of Mars’ atmosphere could be changed forever from the close encounter.
“The image in the center shows a streak … radiating out of the comet’s nucleus (out of frame), possibly indicating the jet from [the] comet’s nucleus,” the Indian Science Research Organisation wrote of the above image sequence on its Facebook mission page.
“Usually jets represent outgassing activity from [the] vents of the comet-nucleus, releasing dust and ice crystals. The outgassing activity gradually increases as the comet moves closer to the Sun.”
The comet’s dust likely produced a meteor shower or meteor storm when particles from it crashed into the upper atmosphere, which “literally changed the chemistry,” added Jim Green, director of NASA’s planetary science division, in a recent discussion highlighted on an agency blog.
The agency says the dust created vaporized metals, which will eventually transform to dust or “meteoric smoke.” MAVEN (which stands for Mars Atmosphere and Volatile EvolutioN) will be monitoring the long-term effects. Possible results include high-altitude clouds or at the most extreme, maybe permanently altering what the chemistry of the atmosphere is. Not a bad thing for a mission to study shortly after it arrived at Mars.
You can view more science results from NASA’s studies of Siding Spring in this recent Universe Today story from Bob King, which talks in more detail about the meteor shower, new layers in the Mars atmosphere and the omnipresent dust.
NASA’s newest Mars spacecraft is “go” for at least a year — and potentially longer. After taking a time-out from commissioning to observe Comet Siding Spring whizz by the Red Planet in October, the Mars Atmosphere and Volatile Evolution (MAVEN) officially began its science mission Monday (Nov. 17). And so far things are going well.
“From the observations made both during the cruise to Mars and during the transition phase, we know that our instruments are working well,” stated principal investigator Bruce Jakosky, who is with NASA’s Goddard Space Flight Center in Maryland. “The spacecraft also is operating smoothly, with very few ‘hiccups’ so far. The science team is ready to go.”
MAVEN arrived in orbit Sept. 16 after facing down and overcoming a potential long delay for its mission. NASA and other federal government departments were in shutdown while MAVEN was in final launch preparations, but the mission received a special waiver because it is capable of communicating with the rovers on Mars. Given the current relay spacecraft are aging, MAVEN could serve as the next-generation spacecraft if those ones fail.
But that’s providing that MAVEN can last past the next year in terms of hardware and funding. Meanwhile, its primary science mission is better understanding how the atmosphere of Mars behaves today and how it has changed since the Red Planet was formed.
“The nine science instruments will observe the energy from the Sun that hits Mars, the response of the upper atmosphere and ionosphere, and the way that the interactions lead to loss of gas from the top of the atmosphere to space,” Jakosky added.
“Our goal is to understand the processes by which escape to space occurs, and to learn enough to be able to extrapolate backwards in time and determine the total amount of gas lost to space over time. This will help us understand why the Martian climate changed over time, from an early warmer and wetter environment to the cold, dry planet we see today.”
“Thousands of meteors per hour would have been visible — truly astounding to the human eye.” That’s Nick Schneider’s description of what you and I would have seen standing on Mars during Comet Siding Spring’s close flyby last month. “It would have been really mind-blowing,” he added. Schneider is instrument lead for MAVEN’s Imaging Ultraviolet Spectrograph (IUVS).
He and a group of scientists who work as lead investigators for instruments on the MAVEN and Mars Reconnaissance Orbiter (MRO) spacecraft shared the latest results from the comet flyby during a media teleconference earlier today. There were many surprises. Would we expect anything less from a comet?
Here’s a summary of the results:
A very dusty ice ball – The comet’s dust tail and the amount of dust in its coma were much larger than expected, prompting Jim Green, director of NASA’s Planetary Science Division in Washington, to remark: “It makes me very happy we hid them (the spacecraft) on the backside of Mars. That really saved them.” Siding Spring dumped several tons of fine dust into the Martian atmosphere prompting a spectacular meteor shower and possibly causing a yellow, twilight afterglow above the Curiosity landing site from vaporizing sodium atoms contained in the minerals. That, and dust in the mid-levels of the atmosphere at the time contributed to the rover’s difficulty in getting good photos of the comet itself. Scientists are still examining the images.
Chemistry of Mars’ atmosphere changed – Dust vaporized in the intense meteor shower produced a striking increase in the amount of magnesium, iron and others metals in Mars’ upper atmosphere. “We were pressed back in our chairs,” said Mike Schneider. The bombardment created a temporary new layer of comet-tainted air and may have acted as condensation nuclei for the formation of high-altitude clouds. MAVEN’s Neutral Gas and Ion Mass Spectrometer (NGIMS) recorded huge spikes in the levels of eight different metals during the comet’s passage and then trailed off a day or so later. “They came to MAVEN as a free sample from no less than an Oort Cloud comet,” said Mehdi Benna, instrument scientist for MAVEN’s Neutral Gas and Ion Mass Spectrometer.
Flaming comet dust creates new ionospheric layer – Comet dust slamming into the atmosphere at 125,000 mph (56 km/sec) knocked electrons loose from atoms in the thin Martian air 50-60 miles (80-100 km) high, ionizing them and creating a very dense ionization layer in the planet’s lower ionosphere seven hours after the comet’s closest approach. Normally, Mars ionosphere is only seen on the dayside of the planet, but even when the MARSIS instrument on Mars Express beamed radio waves through the atmosphere on the nightside of the planet, it picked up a very strong signal.
Nucleus spins once during your work day – Comet Siding Spring’s icy core spins once every 8 hours and its irregular shape causes strong variations in the comet’s brightness. The comet’s size appears less certain – at least for the moment – with estimates anywhere between a few hundred meters to 2 km (1.2 miles). More analysis on images taken by MRO’s HiRISE camera should narrow that number soon.
Dust motes of many sizes – Color variations across Siding Spring’s coma seen by Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) indicate it’s releasing dust particles of different sizes – big and little.
The scientists involved in the encounter couldn’t be happier with how the instruments functioned and the amount of hard data returned. Said Jim Green: “We are so lucky to observe this once-in-a-lifetime event.” How true when you consider that it takes about 8 million years for a comet from the Oort Cloud, that vast reservoir of frozen comets extending nearly a light year from the Sun, to get here in the first place. Nick Schneider put it another way:
“Not only is this a free sample of the Oort Cloud in Mars’ atmosphere, but it gives us a chance to learn more about Mars itself.”
If you’d like to listen in to the hour-long teleconference at any time, it’ll be up for the next week or so HERE.
India’s Mars Orbiter Mission (MOM) has delivered another sweet treat – a stunning view of our Solar System’s largest volcano and the largest canyon.
Just days ago, MOM captured a new global image of the Red Planet dominated by Olympus Mons and Valles Marineris – which is the largest known volcano and the largest known canyon in the Solar System, respectively.
Situated right in between lies a vast volcanic plateau holding a trio of huge volcanoes comprising the Tharsis Bulge: Arsia Mons, Pavonis Mons, and Ascraeus Mons. All four volcanoes are shield volcanoes.
To give an idea of its enormity, Olympus Mons stands about three times taller than Mount Everest and is about the size of Arizona.
Olympus Mons is located in Mars’ western hemisphere and measures 624 kilometers (374 miles) in diameter, 25 km (16 mi) high, and is rimmed by a 6 km (4 mi) high scarp.
Valles Marineris is often called the “Grand Canyon of Mars.” It spans about as wide as the entire United States.
The Indian Space Research Organization (ISRO), India’s space agency which designed and developed the orbiter released the image on Oct. 17, barely two days ahead of the planet’s and spacecrafts’ extremely close encounter with comet Siding Spring.
By the way, a relieved ISRO tweeted MOM’s survival of her close shave with the once-in-a-lifetime cometary passage with gusto, soon after the swingby:
“Phew! Experience of a lifetime. Watched the #MarsComet #SidingSpring whizzing past the planet. I’m in my orbit, safe and sound.”
The new global image was taken by the tri-color camera as MOM swooped around the Red Planet in a highly elliptical orbit whose nearest point to Mars (periapsis) is at 421.7 km and farthest point (apoapsis) at 76,993.6 km, according to ISRO.
To date ISRO has released four global images of the Red Planet, including a 3-D view, reported here.
Olympus Mons, the Tharsis Bulge, and Valles Marineris are near the equator.
Valles Marineris stretches over 4,000 km (2,500 mi) across the Red Planet, is as much as 600 km wide, and measures as much as 7 kilometers (4 mi) deep.
Here’s a comparison view of the region taken by NASA’s Viking 1 orbiter in the 1970s.
MOM is India’s first deep space voyager to explore beyond the confines of her home planet’s influence and successfully arrived at the Red Planet only one month ago after the “history creating” orbital insertion maneuver on Sept. 23/24 following a ten month journey.
The $73 million MOM mission is expected to last at least six months.
MOM’s success follows closely on the heels of NASA’s MAVEN orbiter which also successfully achieved orbit barely two days earlier on Sept. 21 and could last 10 years or more.
With MOM’s arrival, India became the newest member of an elite club of only four entities that have launched probes that successfully investigated Mars – following the Soviet Union, the United States, and the European Space Agency (ESA).
Stay tuned here for Ken’s continuing Earth and planetary science and human spaceflight news.
We present here a compendium of Universe Today articles on comet Siding Spring. Altogether 18 Universe Today stories and counting have represented our on-going coverage of a once in a lifetime event. The articles beginning in February 2013, just days after its discovery, lead to the comet’s penultimate event – the flyby of Mars, October 19, 2014. While comet Siding Spring will reach perihelion just 6 days later, October 25, 2014, it will hardly have sensed the true power and impact that our Sun can have on a comet.
Siding Spring’s Oort Cloud cousin, Comet ISON in November 2013 encountered the Sun at a mere 1.86 million km. The intensity of the Sun’s glare was 12,600 times greater than what Siding Spring will experience in a few days. Comet ISON did not survive its passage around the Sun but Comet Siding Spring will soon turn back and begin a very long journey to its place of origin, the Oort Cloud far beyond Pluto.
The closest approach for comet Siding Spring with the Sun – perihelion is at a distance of 1.39875 Astronomical Units (1 AU being the distance between the Earth and Sun), still 209 million km (130 million miles). The exact period of the comet is not exactly known but it is measured in millions of years. In my childhood astronomy book, it stated that comet Halley, when it is at its furthest distance from the Sun, is moving no faster than a galloping horse. This has also been all that comet Siding Spring could muster for millions of years – the slightest of movement in the direction of the Sun.
It is only in the last 3 years, out all the millions spent on its journey, that it has felt the heat of the Sun and been in proximity to the planetary bodies of our Solar System. This is story of all long period comets. A video camera on Siding Spring would have recorded the emergence and evolution of one primate out of several, one that left the trees to stand on two legs, whose brain grew in size and complexity and has achieved all the technological wonders (and horrors) we know of today.
Now with its close encounter with Mars, the planet’s gravity will bend the trajectory of the comet and reduce its orbital period to approximately one million years. No one will be waiting up late for its next return to the inner Solar System.
It is also unknown what force in the depths of the Oort cloud nudged the comet into its encounter with Mars and the Sun. Like the millions of other Oort cloud objects, Siding Spring has spent its existence – 4.5 Billion years, in the darkness of deep space, with its parent star, the Sun, nothing more than a point of light, the brightest star in its sky. The gravitational force that nudged it may have been a passing star, another cometary body or possibly a larger trans-Neptunian object the size of Pluto and even as large as Mars or the Earth.
The forces of nature on Earth cause a constant turning over geological features. Our oceans and atmosphere are constantly recycling water and gases. The comets that we receive from the Oort Cloud are objects as old as our Solar System. Yet it is the close encounter with Mars that has raised the specter of an otherwise small ordinary comet. All these comets from deep space are fascinating gems nearly unaltered for 1/3rd of the time span of the known Universe.
Universe Today’s Siding Spring Compendium
2014/10/17: Weekly Space Hangout Oct 17 2014
2014/09/09: Tales Tails Of Three Comets
2014/07/26: NASA Preps For Nail Biting Comet Flyby Of Mars
2014/01/29: Neowise Spots Mars Crossing Comet
2013/03/05: Update On The Comet That Might Hit Mars
2013/02/26: Is A Comet On A Collision Course With Mars
Host: Fraser Cain (@fcain)
It’s been less than a month since NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft slipped into orbit. But it’s already provided mission scientists their first look at Mars’ tenuous atmosphere.
“Everything is performing well so far,” said Bruce Jakosky, the mission’s principle investigator, in a news release. “All the instruments are showing data quality that is better than anticipated at this early stage of the mission. The spacecraft is performing beautifully. It’s turning out to be an easy and straightforward spacecraft to fly, at least so far. It really looks as if we’re headed for an exciting science mission.”
Data collected by MAVEN will answer a longstanding puzzle among planetary scientists. There’s ample evidence that early in the Red Planet’s history it had a much denser atmosphere. Rain fell from the sky and water carved its surface. But then the atmosphere vanished, and scientists are unsure why.
One leading theory is that the gas escaped to space, stripped away by the solar wind rushing past. (Click here to see a cool animation of that process.) Here on Earth, our magnetosphere helps protect our atmosphere from the solar wind. But once Mars lost its own magnetosphere, billions of years ago, its atmosphere became vulnerable.
MAVEN’s spectrometers will attempt to determine if hydrogen atoms, torn from water molecules by ultraviolet sunlight, are escaping to space and at what rate. Already, the spacecraft has observed the edges of the Martian atmosphere using its Imaging Ultraviolet Spectrograph (IUVS) camera, which is sensitive to the sunlight reflected by the atoms.
“With these observations, MAVEN’s IUVS has obtained the most complete picture of the extended Martian upper atmosphere ever made,” said team member Mike Chaffin from Colorado University at Boulder.
So far scientists have used IUVS to create a map of Mars’ ozone. “With these maps we have the kind of complete and simultaneous coverage of Mars that is usually only possible for Earth,” said team member Justin Deighan, also from CU-Boulder.
There will be about two weeks of additional instrument calibration and testing before MAVEN starts its primary science mission in early to mid-November. It will then likely take a few additional months to build up enough measurements to have a clear sense of what’s going on. But the initial results are promising.
It was 20 years ago this past July when images of Jupiter being pummeled by a comet caught the world’s attention. Comet Shoemaker-Levy 9 had flown too close to Jupiter. It was captured by the giant planet’s gravity and torn into a string of beads. One by one the comet fragments impacted Jupiter — leaving blemishes on its atmosphere, each several times larger than Earth in size.
Until that event, no one had seen a comet impact a planet. Now, Mars will see a very close passage of the comet Siding Spring on October 19th. When the comet was first discovered, astronomers quickly realized that it was heading straight at Mars. In fact, it appeared it was going to be a bulls-eye hit — except for the margin of error in calculating a comet’s trajectory from 1 billion kilometers (620 million miles, 7 AU) away.
It took several months of analysis for a cataclysmic impact on Mars to be ruled out. So now today, Mars faces just a cosmic close shave. But this comet packs enough energy that an impact would have globally altered Mars’ surface and atmosphere.
So what should we Earthlings gather from this and other events like it? Are we next? Why or why not should we be prepared for impacts from these mile wide objects?
For one, ask any dinosaur and you will have your answer.
One can say that Mars was spared as were the five orbiting spacecraft from India (Mars Orbiter Mission), the European Union (Mars Express) and the United States (MOD, MRO, MAVEN). We have Scottish-Australian astronomer Robert McNaught to thank for discovering the comet on January 3, 2013, using the half meter (20 inch) Uppsala Southern Schmidt Telescope at Siding Spring, Australia.
Initially the margin of error in the trajectory was large, but a series of observations gradually reduced the error. By late summer 2014, Mars was in the clear and astronomers could confidently say the comet would pass close but not impact. Furthermore, as observations accumulated — including estimates of the outpouring of gases and dust — comet Siding Spring shrunk in size, i.e. the estimates of potentially tens of kilometers were down to now 700 meters (4/10th of a mile) in diameter. Estimates of the gas and dust production are low and the size of the tail and coma — the spherical gas cloud surrounding the solid body — are small and only the outer edge of both will interact with Mars’ atmosphere.
Yet, this is a close call for Mars. We could not rule out a collision for over six months. While this comet is small, it is moving relative to Mars at a speed of 200,000 kilometers/hour (125,000 mph, 56 km/sec). This small body packs a wallop. From high school science or intro college Physics, many of us know that the kinetic energy of an object increases by the square of the velocity. Double the velocity and the energy of the object goes up by 4, increase by 3 – energy increases by 9.
So the close shave for Mars is yet another wake up call for the “intelligent” space faring beings of the planet Earth. A wake up call because the close passage of a comet could have just as easily involved Earth. Astronomers would have warned the world of a comet heading straight for us, one that could wipe out 70% of all life as happened 65 million years ago to the dinosaurs. Replace dinosaur with humans and you have the full picture.
Time would have been of the essence. The space faring nations of the world — those of the EU, and Russia, the USA, Japan and others — would have gathered and attempted to conceive some spacecrafts with likely nuclear weapons that could be built and launched within a few months. Probably several vehicles with weapons would be launched at once, leaving Earth as soon as possible. Intercepting a comet or asteroid further out would give the impulse from the explosions more time to push the incoming body away from the Earth.
There is no way that humanity could sit on their collective hands and wait for astronomers to observe and measure for months until they could claim that it would just be a close call for Earth. We could imagine the panic it would cause. Recall the scenes from Carl Sagan’s movie Contact with people of every persuasion expressing at 120 decibels their hopes and fears. Even a small comet or asteroid, only a half kilometer – a third of a mile in diameter would be a cataclysmic event for Mars or Earth.
But yet, in the time that has since transpired from discovery of the comet Siding Spring (1/3/2013), the Chelyabinsk asteroid (~20 m/65 ft) exploded in an air burst that injured 1500 people in Russia. The telescope that discovered Comet Siding Spring was decommissioned in late 2013 and the Southern Near-Earth Object Survey was shutdown. This has left the southern skies without a dedicated telescope for finding near-Earth asteroids. And proposals such as the Sentinel project by the B612 Foundation remain underfunded.
We know of the dangers from small celestial bodies such as comets or asteroids. Government organizations in the United States and groups at the United Nations are discussing plans. There is plenty of time to find and protect the Earth but not necessarily time to waste.
Previous U.T. Siding Spring stories:
“What Comets, Parking Lots and Charcoal Have in Common“, Bob King, Sept 5, 2014
“MAVEN Mars Orbiter Ideally Poised to Uniquely Map Comet Siding Spring Composition
– Exclusive Interview with Principal Investigator Bruce Jakosky”, Ken Kremer“, Sept 5, 2014
“NASA Preps for Nail-biting Comet Flyby of Mars“, BoB King, July 26,2014