Tag: university of colorado

News from Mars: MAVEN Orbiter Arrives!

maven_tv_backdropIn November 2013, NASA launched the Mars Atmosphere and Volatile Evolution (MAVEN) space probe from Cape Canaveral. Described as a “time machine” for Mars, the orbiter would spend the next ten months traversing space, assuming an orbit around the Red Planet, and look for an answer as to how Mars went from being a planet with an atmosphere and water to the dried out husk that we know today.

And this evening, after trekking some 711 million kilometers (442 million-mile) across our Solar System, MAVEN will have arrived in orbit around Mars and will begin its year-long mission to study the planet’s upper atmosphere. The arrival will be broadcast live, courtesy of NASA TV and Space.com. The live webcast will run from 9:30 p.m. to 10:45 p.m. EDT (0130 to 0245 GMT), and if all goes well, MAVEN will enter orbit around Mars at 9:50 p.m. EDT (0250 GMT).

maven_launchAs David Mitchell, NASA’s MAVEN project manager at the Goddard Space Flight Center in Greenbelt, Maryland, said in a statement:

So far, so good with the performance of the spacecraft and payloads on the cruise to Mars. The team, the flight system, and all ground assets are ready for Mars orbit insertion.

Though plans to study Mars’ atmosphere in detail have been in the works for years, the MAVEN program received a big push from the ongoing efforts from the Curiosity rover. During its ongoing mission to study the surface of Mars, Curiosity was able to confirm that Mars had extensive surface water billions of years ago. This revelation came very early in the mission, and indicated some rather interesting things about Mars’ past.

Mars-snow-header-640x353For instance, although Mars is now too cold for flowing water today, it might have had a thicker atmosphere in the past that warmed its surface and allowed the liquid to remain stable on the surface. And while scientists have a pretty good idea how it was lost (i.e. too far our Sun, too low a gravity field), the rate of loss and when it disappeared are just some of the questions that MAVEN will attempt to answer.

Much of what scientists know about Mars’ upper atmosphere comes from just a few minutes’ worth of data from the two Viking landers that took measurements as they made their way to the Martian surface in the 1970s. This time around, NASA will be able to collect data for an entire year, gathering far more data than either the Viking landers or any other spacecraft has since had the opportunity to do.

maven_atmo1As Bruce Jakosky, the mission’s principal investigator at the University of Colorado, Boulder’s Laboratory for Atmospheric and Space Physics, explained it:

The MAVEN science mission focuses on answering questions about where did the water that was present on early Mars go, about where did the carbon dioxide go. These are important questions for understanding the history of Mars, its climate, and its potential to support at least microbial life.

NASA scientists understand that Mars’ upper atmosphere acts as an escape zone for molecules floating dozens of miles from the planet’s surface. They theorize that as the solar wind hits the atmosphere, the radiation strips away the lighter molecules and flings them into space forever. To test this hypothesis, MAVEN will be examining the state of Mars’ upper atmosphere, and ionosphere to determine its interactions with the solar wind.

maven_atmosphereIn so doing, NASA hopes to determine what the current rates of escape are for neutral gases and ions, and thus get a better picture of how long it took for the atmosphere to degrade and when it began degrading. The upper atmosphere of Mars likely changes as the sun’s activity increases and decreases, which is why MAVEN investigators hope to run the mission for longer than a year.

MAVEN will began making science measurements around Nov. 8, due to it taking a short break from its commissioning phase to watch Comet Siding Spring pass close by on Oct. 19. The $671 million MAVEN spacecraft is one of two missions that launched toward Mars last November and which are making their arrival this month. The other probe is India’s Mars Orbiter Mission, which launched just before MAVEN and will arrive at the Red Planet this Wednesday (Sept. 24).

It is an exciting time for space exploration, and the coming years are sure to be characterized by an escalating and accelerating rate of learning. Be sure to head on over to Space.com to watch the arrival broadcast live. And be sure to check out the following videos – the Mars Arrival trailer; NASA Goddard Center’s “Targeting Mars” video; and the NASA MAVEN PSA, hosted by LeVar Burton:

MAVEN Mars Arrival Trailer:


Targeting Mars:


LeVar Burton Shares MAVEN’s Story:


Sources: space.com, (2), nasa.gov

Global Warming Slowed by Volcanoes

Klyuchevskaya Volcano. NASA Goddard Space Flight Center
Klyuchevskaya Volcano. NASA Goddard Space Flight Center

Global mean temperatures have been rising in recent years, consistent with every projection provided by Climate Change specialists and planetary ecologists. However, it now seems as though the rate of increase is not as bad as it should have been, thanks to a series of small-to-moderate-sized volcanic eruptions that have spewed sunlight-blocking particles high into the atmosphere.

Between 2000 and 2010, the average atmospheric concentration of carbon dioxide rose more from about 370 parts per million to nearly 390. According to Ryan Neely III, an atmospheric scientist at the University of Colorado, Boulder, if that uptick were the only factor driving climate change, the average global temperature would have risen about 0.2°C. But a surge in the concentration of light-scattering particles in the stratosphere countered as much as 25% of that potential temperature increase.

Sanpedropable Volcano as seen from the ISS
San Pedro Volcano, as seen from the ISS

In addition, Neely and his colleagues ran a series of simulations that indicated that human the human contribution of aerosols to the stratosphere – which would have had a counteractive effect to the carbon – was minimal between 2000 and 2010. William Randel, an atmospheric scientist at the National Center for Atmospheric Research in Boulder claimed that the pattern of stratospheric particulate variations during the past decade “shows the fingerprint of volcanoes, with the right episodes showing up at the right time.”

For some time now, researchers and ecologists have known that sulfur dioxide, a major biproduct of volcanic eruptions, has a global cooling effect. Once introduced into the upper atmosphere, this particulate matter blocks out solar radiation and prevents it from being absorbed by the Earth’s soil, water, and plant life. In fact, it was a massive series of eruptions which took place during the Cretaceous–Paleogene Era that is believed to be linked to the extinction of the dinosaurs.

converted PNM fileFor many years, geoengineers have considered releasing sulfur dioxide into the upper atmosphere in order to slow down the process of Climate Change, a measure intended to give Earth’s scientists more time to develop alternative fuels and its people more time to get their act together. However, at this juncture it seems that the planet has obliged us and given us a bit of window, and completely unheeded.

It’s good to know that human agency alone does not determine the course this planet will take. At the same time however, one should not get too enthused and think this means we’re in for a big reprieve. Based on the most recent data, humanity still only has a few decades before the worst begins to happen and our world slowly becomes uninhabitable.

Source: sciencemag.org, Wired.com