Crashing rockets could lead to novel sample-return technology - Video

An artist’s conception shows a sampling rocket, with a tether linking a return capsule inside the rocket to a recovery craft. 

Credit: Chad Truitt / UW

During spring break the last five years, a University of Washington class has headed to the Nevada desert to launch rockets and learn more about the science and engineering involved.

Sometimes, the launch would fail and a rocket smacked hard into the ground.

This year, the session included launches from a balloon that were deliberately directed into a dry lakebed.

Far from being failures, these were early tests of a concept that in the future could be used to collect and return samples from forbidding environments – an erupting volcano, a melting nuclear reactor or even an asteroid in space.

"We're trying to figure out what the maximum speed is that a rocket can survive a hard impact," said Robert Winglee, a UW professor of Earth and space sciences, who heads that department and leads the annual trek to the desert.

The idea for a project called "Sample Return Systems for Extreme Environments" is that the rocket will hit the surface and, as it burrows in a short distance, ports on either side of the nose will collect a sample and funnel it to an interior capsule.

That capsule will be attached by tether to a balloon or a spacecraft, which would immediately reel in the capsule to recover the sample.

"The novel thing about this is that it developed out of our student rocket class. It's been a successful class, but there were a significant number of rockets that went ballistically into the ground. We learned a lot of physics from those crashes," Winglee said.

The technology, which recently received $500,000 over two years from NASA Innovative Advanced Concepts, could have a number of applications, he said.



UW Earth and space sciences faculty and students used a kite to hoist a rocket high above the Nevada desert in March 2013, then fired the rocket directly into a dry lakebed.

On Earth, it would allow scientists a relatively safe way of recovering samples in areas of high contamination, such as Japan's Fukushima Daichi nuclear power plant and the Chernobyl nuclear power facility in Ukraine, both of which suffered catastrophic failures.

Or it could collect samples from an erupting volcano to give Earth scientists a better understanding of the processes at work during one of nature's most violent shows.

In either case, the tethered sample-return capsule could be hauled in by a balloon or a plane.

Novel analysis method reveals more about the enigmatic Quasar

The interaction of a supermassive black hole and a disk of accreting matter, called a quasar, can be seen at the center of a faraway galaxy in this artist's concept. 

It consists of a dusty, doughnut-shaped cloud of gas and dust that feeds a central supermassive black hole. 

As the black hole feeds, the gas and dust heat up and spray out different kinds of light, as illustrated by the white rays. 

In the nearly six decades since quasars were discovered, the list of these energetic galaxies powered by supermassive black holes has grown to more than 100,000 – enough examples to reveal important information about the quasar population as a whole.

But attempts to conduct a celestial census of these powerful objects have been limited by a fundamental problem: Although quasars are bright, they also span billions of light years in distance from Earth. Just as with stars in an urban sky, the closest quasars can be seen even if they are dim, while the oldest and most distant ones can be seen only if they are bright.

This means astrophysicists have to study a sample with big differences among individual members, including distance, age, brightness and type of radiation emitted.

Astrophysicists with the Kavli Institute for Particle Astrophysics and Cosmology, a joint SLAC-Stanford institute, found a way to reach past these limitations: They improved an algorithm that homes in on important commonalities of a population of objects while taking into account the limitations and biases for observations made in multiple types of electromagnetic radiation, such as optical light or radio waves – two of the most important wavelengths for studying quasars.

In the process they shed new light on a contentious question: Are there two types of quasars, with one "louder" in radio than the other, or is there just one type with emissions that vary widely across the electromagnetic spectrum?

A recent paper in The Astrophysical Journal details how the team, including KIPAC scientist Jack Singal, KIPAC member and Stanford professor Vahe Petrosian and KIPAC alumnus Lukasz Stawarz, improved upon an algorithm developed more than a decade ago by Petrosian and Bradley Efron, a respected statistics professor at Stanford.

After validating their algorithm with a small sample, the team turned it loose on the largest sample of quasars yet available: the Sloan Digital Sky Survey (SDSS) Data Release 7 catalog, which has optical-light measurements for more than 100,000 quasars, plus data from the FIRST radio survey, which has more than 400,000 celestial radio sources, to achieve a huge combined sample of radio and optical quasars for analysis.

The team found that quasars have, on average, grown steadily dimmer in both radio and optical light over the history of the universe, but have dimmed more in radio than in optical – dramatically so.

This analysis also supports the "one quasar population" model, and both that and the greater dimming in radio relative to optical light are sure to spark controversy.

Regardless, the work represents what the authors consider to be the most rigorous analysis yet of the evolution of quasars in both radio and optical emissions.

According to Singal, the technique is also useful for studying any population of objects that can be found at widely varying distances – for example, blazars or gamma-ray bursts.

More information: iopscience.iop.org/0004-637X/764/1/43