From New York and Northern New Jersey

Take the New Jersey Turnpike South to Exit 4 (Route 73).
Follow 73 North to the Betsy Ross Bridge (left exit).
Take the Betsy Ross Bridge to 95 South to 676 West (Central Philadelphia).
Follow 676 West to 76 East Exit (Int'l. Airport).
Follow signs for Exit 345 (3/10 of a mile – 30th St./University City).
Go under bridge and immediately get into the right hand lane, which is Exit 345.
Turn right at the top of the ramp and go around 30th St. Station to the first traffic light.
For further instructions, see Parking Options.

From Princeton, Trenton, and Points North

Take 95 South to 676 West/Central Philadelphia.
Follow 676 West to 76 East Exit (Int'l. Airport).
Follow signs for Exit 345 (3/10 of a mile – 30th St./University City).
Go under bridge and get into the right hand lane, which is Exit 345.
Turn right at the top of the ramp and go around 30th St. Station to the first traffic light.
For further instructions, see Parking Options.

From Western Pennsylvania

Take the PA Turnpike to Exit 326 (Valley Forge).
Follow 76 East to Exit 345 (30th Street).
Turn right at the top of the ramp and go around 30th St. Station to the first traffic light.
For further instructions, see Parking Options.

From Northeastern Pennsylvania

Take the PA Turnpike Northeast Extension South to 76 East.
Follow 76 East to Exit 345 (30th Street).
Turn right at the top of the ramp and go around 30th St. Station to the first traffic light.
For further instructions, see Parking Options.

From Airport and Points South

Take 95 North to 676 West (Exit 22 – left side exit).
Follow 676 West to 76 East. Exit at 76 East (Int'l. Airport).
Follow signs for Exit 345 (3/10th of a mile – 30th St./University City).
Go under bridge and get into the right hand lane, which is Exit 345.
Follow Exit 345 (30th St.) to first traffic light. For further instructions, see Parking Options.

Many things

The Aircraft Laser Infrared Absorption Spectrometer (ALIAS) instrument is a high resolution four-channel scanning Tunable Diode Laser (TDL) and Quantum-Cascade (QC) laser spectrometer (3.4 to 8 µm) that makes direct, simultaneous measurements of (e.g. HCl, NO2, CH4, N2O, CO, water isotopes) (including vertical profiles of the tracers) in the stratosphere and troposphere at sub-parts-per-billion sensitivities. The whole instrument weighs 160 lbs. The measurement technique is based upon using TDL and QC lasers operating from 3.4 to 8 µm scanning over absorption lines recorded using second harmonic absorption spectroscopy over an 80-m pathlength in a 1-m multipass optical cell of the Herriott design. ALIAS has flown over 300 times in 7 major NASA missions: AASE-II, SPADE, STRAT, ASHOE/MAESA, POLARIS, SOLVE, and CRYSTAL-FACE.

Chemical Climate Changes

Carbon dioxide levels in the atmosphere, as measured from gas bubbles trapped in ice cores, has increased since the start of the industrial revolution in the 19th century from about 280 to around 380 parts per million (by volume). Direct measurements over the last 30 years show an average increase of 1.5 ppm/year. Much of this increase, which contributes to global warming, is the result of burning fossil fuels and to some extent deforestation. Total carbon content in the Earth system is held in three main reservoirs, the atmosphere, the ocean, and the terrestrial biosphere (see the Global Carbon Cycle for more information on these sinks).

Besides carbon dioxide there are other gases, such as methane, ozone, and of curse water vapour which have a role to play in the greenhouse effect. Unlike carbon dioxide, the concentration and distribution of these gases are highly dependent on physical and chemical reactions in the atmosphere. In the lower part of the atmosphere, the concentration of methane depends on the rate of its destruction by the hydroxyl radical. The concentration of ozone depends on various short lived precursor gases (carbon monoxide, oxides of nitrogen, and non-methane hydrocarbons) and transport from the stratosphere.

The Galactic Habitable Zone

Astrobiologists’ new, grander view of habitability gets even more expansive when they look out to the galaxy around us. The Milky Way contains perhaps 200 billion stars. Now that we know a significant fraction of stars have planets, that number translates into (as Carl Sagan might say) billions and billions of worlds. Red dwarf stars, which are by far the most common stars in our galaxy, were once considered unlikely places to find Earth-like planets, but new studies contradict that view. And the extremophiles tell us that life could potentially take hold even on planets not much like our own.
All of that is the good news. But things are not quite so simple, because galaxies—like solar systems—have habitability zones of their own. Not all parts of a galaxy are suited to life. In 2004 astrobiologist Charley Lineweaver of Australian National University published a paper that broadly mapped out our galaxy, the Milky Way, with an eye toward possibilities and dangers for alien biology. In this case, the crucial factor is not the presence of water; it is the proximity of violent, massive stars.

Beyond the Science

Things were not looking so good for alien life in 1976, after the Viking I spacecraft landed on Mars, stretched out its robotic arm, and gathered up a fist-size pile of red dirt for chemical testing. Results from the probe’s built-in lab were anything but encouraging. There were no clear signs of biological activity, and the pictures Viking beamed back showed a bleak, frozen desert world, backing up that grim assessment. It appeared that our best hope for finding life on another planet had blown away like dust in a Martian windstorm.
What a difference 33 years makes. Back then, Mars seemed the only remotely plausible place beyond Earth where biology could have taken root. Today our conception of life in the universe is being turned on its head as scientists are finding a whole lot of inviting real estate out there. As a result, they are beginning to think not in terms of single places to look for life but in terms of “habitable zones”—maps of the myriad places where living things could conceivably thrive beyond Earth. Such abodes of life may lie on other planets and moons throughout our galaxy, throughout the universe, and even beyond.

Masten Space Systems - New Hiring, New Engine, and XA-0.1 Replacement Plans

MSS Blog: It’s the beginning of a new year, and there are many changes afoot at MSS, so I figured it was about time for a bit of an update. A lot of people were curious about what direction we would end up taking after we damaged our vehicle last month, so I wanted to discuss some of our plans for this year.
MSS Now Hiring One of the biggest changes that we’re undergoing at the moment is an effort to augment the core team here at MSS. We haven’t had any real changes to our core team since early 2005, but situations change over time, and we’ve been recognizing the need to expand and diversify our skillset as a team. Basically, we came to the conclusion early last year that there are a couple of areas that we really need to have someone in-house with solid expertise in, particularly Guidance, Navigation and Control. We’ve updated our careers page with more details, but I’d like to go into some of the reasoning for why we’re looking to fill some of these positions.
GN&C Engineer Even though we’ve been working with outside groups to provide us with expertise in this area, we’ve long since come to the conclusion that having someone in-house who has a good understanding of controls engineering is very important. Having someone with real experience in that area is critical to properly specifying and designing actuators and other subsystems. A lot of the control systems related challenges we’ve had to fight through over the past year and a half came from not knowing what to expect, “failure to overcommunicate” when it came to specifications, and just the general learning curve of figuring out what data was important and how to actually verify that things were performing the way you expect them to. Quite frankly, the basic rocket propulsion part of our vehicle has been the easy part. Read the rest of this entry »

Masten Space Systems - Quick igniter blog update

Over the weekend I learned LabVIEW and wrote a virtual instrument to do data acquisition on the igniter cart, and calibrated the pressure transducers earlier this week. Today we ran the igniter three more times, so we can start dialing in the correct nozzle throat diameter and orifice sizes. As expected, the igniter chamber pressure is bit more than double the final desired value. Here are the promised Mach diamond photos. Still not as good as they should be, but you can kind of see the first glowing spot in the flames.