Category Archives: Space exploration

Hubble Gazes Into a Black Hole of Puzzling Lightness

The beautiful spiral galaxy visible in the center of the image is known as RX J1140.1+0307, a galaxy in the Virgo constellation imaged by the NASA/ESA Hubble Space Telescope, and it presents an interesting puzzle. At first glance, this galaxy appears to be a normal spiral galaxy, much like the Milky Way, but first appearances can be deceptive!

The Milky Way galaxy, like most large galaxies, has a supermassive black hole at its center, but some galaxies are centered on lighter, intermediate-mass black holes. RX J1140.1+0307 is such a galaxy — in fact, it is centered on one of the lowest black hole masses known in any luminous galactic core. What puzzles scientists about this particular galaxy is that the calculations don’t add up. With such a relatively low mass for the central black hole, models for the emission from the object cannot explain the observed spectrum. There must be other mechanisms at play in the interactions between the inner and outer parts of the accretion disk surrounding the black hole.

Source: NASA

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Catching Cassini’s call

Above Saturn

This week, ESA deep-space radio dishes on two continents are listening for signals from the international Cassini spacecraft, now on its final tour of Saturn.

ESA’s sensitive tracking antennas at New Norcia, Western Australia, and Malargüe, Argentina, are being called in to help with crucial observations during Cassini’s last months in orbit, dubbed the ‘Grand Finale’.

The Cassini–Huygens mission is one of the most successful exploration endeavours ever.

Launched in October 1997, the Cassini orbiter delivered Europe’s Huygens probe to the surface of Saturn’s mysterious moon Titan in 2005, just a few months after becoming the first spacecraft to enter orbit around the giant gas planet.

In addition to Huygens’ historic delivery 12 years ago on 14 January, Cassini has returned a wealth of information from Saturn’s system, including images and other data from the massive planet, its multiple moons and its hauntingly beautiful system of rings.

Huygens landing on Titan

Now running low on fuel, Cassini will be commanded to dive into Saturn’s upper atmosphere on 15 September, where it will burn up like a meteor.

As part of its final ambitious observing plan, the craft began last month making a series of 20 orbits, arcing high above the planet’s north pole then diving down, skimming the narrow F-ring at the edge of the main rings.

Then, starting in April, Cassini will leap over the rings to begin its final series of 22 daring dives, taking it between the planet and the inner edge of the rings.

Between December 2016 and July 2017, ESA’ ground stations will work with NASA’s Deep Space Network to record radio signals transmitted by Cassini across 1.6 billion km, helping scientists to study Saturn’s atmosphere and its enigmatic rings, bringing us closer to understanding its origins.

New Norcia tracking station

They will record signals transmitted from Cassini that have crossed or bounced off Saturn’s atmosphere or rings. Variations in the strength and frequency contain valuable information on the composition, state and structure of whatever they have passed through.

In addition, tiny wobbles in Cassini’s orbit due to the varying pull of gravity can be teased from the signals, helping to build our understanding of the planet’s interior.

First passes

The first three recording passes involving ESA stations were conducted in December, followed by two more on 3 and 10 January. Twenty more deep-space link-ups are scheduled.

“For the first few months of 2017, we’re mostly recording signals that will transit through the ring system or the atmosphere,” says Daniel Firre, the service manager at ESA’s mission control centre in Darmstadt, Germany.

“After April, as Cassini’s orbit gets lower, we’ll switch to recording signals to be used for gravity analysis.”

The recordings – some batches comprising up to 25 GB – are passed to the Cassini radio science team for analysis.

“The ESA stations are helping to acquire extremely important radio science data from Cassini, highlighting how interagency cooperation can make planetary missions even more valuable,” notes Aseel Anabtawi, from the radio science group at NASA’s Jet Propulsion Laboratory.

Some recording contacts between Cassini and Earth will last over 10 hours, and require technically complex handovers of the signal from an ESA to a NASA station and vice versa. In addition, specialists in Darmstadt must perform very precise frequency calculations for the recording passes.

“Supporting Cassini radio science for the mission’s Grand Finale requires not only teamwork at ESA, but also deep collaboration between the agencies,” says ESA’s Thomas Beck, responsible for ground station services.

“This is part of our continuing mutual support that is yielding real scientific and engineering value.”

Source: ESA

NASA Meets the Big Game: Five Things Space and Football Have in Common

As Super Bowl LI in Houston approaches and players, coaches and a host of personnel behind the scenes prepare for the big game in Space City, NASA remains on the cutting edge of human space exploration, setting its sights on the journey to Mars. A football player’s journey to the end zone, though, has a lot more in common to space exploration than one might think. Here are five similarities.

Exercise

Football players must be quick and powerful, honing the physical skills necessary for their unique positions. In space, maintaining physical fitness is a top priority, since astronauts will lose bone and muscle mass if they do not keep up their strength and conditioning, which will result in a reduced capacity to work in space.

Expedition 50 crew members Peggy Whitson (left) and Shane Kimbrough of NASA (right) share fresh fruit that was recently delivered by the HTV-6 cargo vehicle to the International Space Station.

On the International Space Station, astronauts work out about two hours a day and use three unique pieces of exercise equipment. They run on a treadmill with harnesses that hold them to its surface to maintain cardiovascular health, work out on a resistive exercise device that simulates free-weight exercises on Earth to keep up their strength and ride a type of exercise bike for cardiovascular and aerobic conditioning.

NASA is also developing smaller exercise devices for astronauts on longer missions to deep space, where equipment space is limited. Astronauts in Orion will use a device about the size of a large shoe box for both aerobic activity and strength training. Another compact device called the Miniature Exercise Device-2 is currently being evaluated on the space station.

Expedition 47 flight controllers in the Johnson Space Center’s Mission Control watch over the undocking of a spacecraft from the International Space Station. Teamwork plays a vital role in successful missions in space.

Nutrition

Sustaining peak performance through a multi-month season requires players to pay close attention to what they eat. Similarly, astronauts in space must maintain a balanced diet to stay physically and mentally sharp during their missions. However, space poses unique challenges to maintaining optimum nutrition, such as the need to minimize not only the weight of food, but the packaging and trash volume.

Space station crew members have about 200 options to choose from, shipped to the orbital laboratory aboard cargo vehicles. NASA also is working on ways to feed the crew on longer missions, including a months-long journey to Mars that could last about 1,000 days, including transit time. The space station vegetable production system is helping to determine how to regularly grow fresh vegetables in space, and astronaut Shane Kimbrough recently started the third such investigation aboard the station. Scientists are developing new high-calorie food bars to reduce the amount of weight astronauts will have to carry on missions in the Orion spacecraft. Scientists are also looking at packaging food items to keep them edible and nutritious in conditions where there are temperature fluctuations, such as on the surface of Mars.

ESA (European Space Agency) astronaut Samantha Christoforetti works out on the Advanced Resistive Exercise Device on the International Space Station. Routine exercise is critical to keeping crews healthy in space.

Communication

During football games, calling plays and relaying information from coaches on the sidelines or in the booth to players on the field is essential. Coaches communicate directly with quarterbacks and a defensive player between plays via radio frequencies. They must have a secure and reliable system that keeps their competitors from listening in and also keeps loud fan excitement from drowning out what can be heard. Likewise, reliable communication with astronauts in space and robotic spacecraft exploring far into the solar system is key to NASA’s mission success.

A radio and satellite communications network allows space station crew members to talk to ground-based control centers, and for those centers to send commands to the orbital complex. The space station has multiple space-to-ground communications channels that are in near-constant use to allow for voice, video or data transmissions. With hundreds of scientific investigations and technology demonstrations taking place on the space station, this communication is essential to maintaining the space station’s primary function as a research laboratory and is also critical for crew safety. In noisy conditions, players and coaches also use good old-fashioned hand signals to communicate, which is also a technique employed by spacewalking astronauts as a backup to radio communications. When humans reach Mars, communications with the ground will take between seven and 22 minutes to go one way from Earth to the Red Planet.

NASA’s Deep Space Network is an international array of giant radio antennas in California, Spain and Australia that supports interplanetary spacecraft missions, plus a few that orbit Earth. It’s the largest and most sensitive scientific telecommunications system in the world.

Innovative Technology

The days of bulky pads and jersey materials have given way to lightweight materials and innovative technologies that improve safety and allow players to move better. A host of NASA technologies have been adapted for use in sports.

A former NASA engineer invented a treadmill that was licensed to a company that transformed the technology into an enclosed treadmill that uses air pressure to help patients feel up to 80 percent lighter, easing discomfort during rehabilitation. The anti-gravity treadmills are now used by professional sports teams and others to train and speed up recovery after injuries.

To monitor the body temperature of astronauts during spaceflight, NASA teamed up with Johns Hopkins University in the 1980s to develop an ingestible thermometer pill. A commercially available version of the pill has been used by sports teams to detect elevated core body temperature. This NASA spinoff is also used to help keep soldiers, firefighters and first responders safe in dangerous environments.

Included in the recovery regimen for certain football injuries is cold therapy, the use of liquid cooling in a compression garment to reduce swelling and increase blood circulation in the targeted area. An industry-leading provider of these therapeutic garments was founded by a NASA scientist who worked on similar cooling garments for spacesuits.

Teamwork

Some say football is the ultimate team sport, and space exploration is no different. Landing robotic rovers on Mars, sending probes to Jupiter and past Pluto, building the most powerful space telescope ever, operating the space station and developing new spacecraft and rockets for deep space exploration requires the work of thousands of people behind the scenes who dedicate their time, energy and abilities to executing successful missions in space. From engineers who develop hardware and software to enable spacecraft to function to the many people who keep NASA centers running, everyone plays a role in successfully exploring far into the solar system.

Mission control at NASA’s Johnson Space Center in Houston, for example, supports the International Space Station seven days a week, 24 hours a day, 365 days a year—keeping a constant watch on the crew’s activities and monitor spacecraft systems. These highly trained flight controllers have the skills needed to closely monitor and maintain increasingly complex expeditions and respond to unexpected events. Football teams have a similar all-hands-on-deck approach, relying not only on their coaching staff and players, but also on trainers, front-office staff and many others behind the scenes to win games.

Source: NASA

 

Huygens: ‘Ground Truth’ From an Alien Moon

Images taken by Huygens were used to create this view, which shows the probe’s perspective from an altitude of about 6 miles (10 kilometers). Image credit: ESA/NASA/JPL/University of Arizona

2005 Historic Descent to Titan Revisited

After a two-and-a-half-hour descent, the metallic, saucer-shaped spacecraft came to rest with a thud on a dark floodplain covered in cobbles of water ice, in temperatures hundreds of degrees below freezing. The alien probe worked frantically to collect and transmit images and data about its environs — in mere minutes its mothership would drop below the local horizon, cutting off its link to the home world and silencing its voice forever.

Although it may seem the stuff of science fiction, this scene played out 12 years ago on the surface of Saturn’s largest moon, Titan. The “aliens” who built the probe were us. This was the triumphant landing of ESA’s Huygens probe.

Huygens, a project of the European Space Agency, traveled to Titan as the companion to NASA’s Cassini spacecraft, and then separated from its mothership on Dec. 24, 2004, for a 20-day coast toward its destiny at Titan.

The probe sampled Titan’s dense, hazy atmosphere as it slowly rotated beneath its parachutes, analyzing the complex organic chemistry and measuring winds. It also took hundreds of images during the descent, revealing bright, rugged highlands that were crosscut by dark drainage channels and steep ravines. The area where the probe touched down was a dark, granular surface, which resembled a dry lakebed.

Thoughts on Huygens

Today the Huygens probe sits silently on the frigid surface of Titan, its mission concluded mere hours after touchdown, while the Cassini spacecraft continues the exploration of Titan from above as part of its mission to learn more about Saturn and its moons. Now in its dramatic final year, the spacecraft’s own journey will conclude on September 15 with a fateful plunge into Saturn’s atmosphere.

With the mission heading into its home stretch, Cassini team members and NASA leaders look back fondly on the significance of Huygens:

“The Huygens descent and landing represented a major breakthrough in our exploration of Titan as well as the first soft landing on an outer-planet moon. It completely changed our understanding of this haze-covered ocean world.”
— Linda Spilker, Cassini project scientist at NASA’s Jet Propulsion Laboratory, Pasadena, California

“The Huygens images were everything our images from orbit were not. Instead of hazy, sinuous features that we could only guess were streams and drainage channels, here was incontrovertible evidence that at some point in Titan’s history — and perhaps even now — there were flowing liquid hydrocarbons on the surface. Huygens’ images became a Rosetta stone for helping us interpret our subsequent findings on Titan.”
— Carolyn Porco, Cassini imaging team lead at Space Science Institute, Boulder, Colorado

“Cassini and Huygens have shown us that Titan is an amazing world with a landscape that mimics Earth in many ways. During its descent, the Huygens probe captured views that demonstrated an entirely new dimension to that comparison and highlights that there is so much more we have yet to discover. For me, Huygens has emphasized why it is so important that we continue to explore Titan.”
— Alex Hayes, a Cassini scientist at Cornell University, Ithaca, New York

“Twelve years ago, a small probe touched down on an orangish, alien world in the outer solar system, marking humankind’s most distant landing to date. Studying Titan helps us tease out the potential of habitability of this tiny world and better understand the chemistry of the early Earth.”
— Jim Green, director of planetary science at NASA Headquarters, Washington

Source: JPL

The Dust Never Settles on the Space Station

When your house gets dusty, the dust settles, falling down to lower surfaces, awaiting your attention with the vacuum cleaner or duster.  Not so on the International Space Station.  Like any home, it gets dusty, but the particles don’t settle…they float.

And that’s a problem for astronauts living and working there.  Dust can get in their eyes and nose causing irritation and allergic reactions.

Although high efficiency filters are installed on the space station and the astronauts vacuum regularly, there has never been a thorough investigation of airborne particulates until now.

NASA Glenn Research Scientist Dr. Marit Meyer is leading an experiment to sample airborne particles on station to help improve astronaut health and wellness. The experiment involves two types of samplers designed by the RJ Lee Group, which are portable collection devices.

The passive air sampler has several plates with sticky surfaces that collect large particulates floating inside the space station.
Credits: NASA

“Collecting this data will help us to ultimately build a particulate matter monitor so NASA can improve the environment for astronauts on station and other long term missions in deep space,” says Meyer.

The first collection device is an electric sampler placed on the wall near where the astronauts work.  A pump draws air through a cartridge containing a heated channel and across a very small disk.  The airborne particles are drawn inside and get stuck to the surface of the disk.

“For six hours at a time the sampler collects particles as small as nanometer sizes, given off by the astronauts where they exercise and work,” explains Meyer.

She is particularly interested in collecting data from near the cargo bay area.

“When cargo vehicles are opened to retrieve supplies, any particulates inside can circulate into the station and affect the air astronauts breathe,” she says.

Additionally, seven passive samplers are placed near air ducts and vents. These devices have several plates with sticky surfaces that are opened all at once and then closed at different times to collect larger particulates.

“We expect to see lint, skin flakes and metal particles when we study the samples upon their return from the space station,” says Meyer.

When the samplers return to Earth, the cartridges and other samples will be analyzed in a variety of light, laser and electron microscopes.

Source: NASA