All posts by Lucy Ingham

Juno mission: Jupiter’s magnetic field is even weirder than expected

It has long been known that Jupiter has the most intense magnetic field in the solar system, but the first round of results from NASA’s Juno mission has revealed that it is far stronger and more misshapen than scientists predicted.

Announcing the findings of the spacecraft’s first data-collection pass, which saw Juno fly within 2,600 miles (4,200km) of Jupiter on 27th August 2016, NASA mission scientists revealed that the planet far surpassed the expectations of models.

Measuring Jupiter’s magnetosphere using Juno’s magnetometer investigation (MAG) tool, they found that the planet’s magnetic field is even stronger than models predicted, at 7.766 Gaus: 10 times stronger than the strongest fields on Earth.

Furthermore, it is far more irregular in shape, prompting a re-think about how it could be generated.

“Juno is giving us a view of the magnetic field close to Jupiter that we’ve never had before,” said Jack Connerney, Juno deputy principal investigator and magnetic field investigation lead at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

“Already we see that the magnetic field looks lumpy: it is stronger in some places and weaker in others.

An enhanced colour view of Jupiter’s south pole. Image courtesy of NASA/JPL-Caltech/SwRI/MSSS/Gabriel Fiset. Featured image courtesy of NASA/SWRI/MSSS/Gerald Eichstädt/Seán Doran

At present, scientists cannot say for certain why or how Jupiter’s magnetic field is so peculiar, but they do already have a theory: that the field is not generated from the planet’s core, but in a layer closer to its surface.

“This uneven distribution suggests that the field might be generated by dynamo action closer to the surface, above the layer of metallic hydrogen,” said Connerney.

However, with many more flybys planned, the scientists will considerable opportunities to learn more about this phenomenon, and more accurately pinpoint the bizarre magnetic field’s cause.

“Every flyby we execute gets us closer to determining where and how Jupiter’s dynamo works,” added Connerney.

With each flyby, which occurs every 53 days, the scientists are treated to a 6MB haul of newly collected information, which takes around 1.5 days to transfer back to Earth.

“Every 53 days, we go screaming by Jupiter, get doused by a fire hose of Jovian science, and there is always something new,” said Scott Bolton, Juno principal investigator from the Southwest Research Institute in San Antonio.

A newly released image of Jupiter’s stormy south pole. Image courtesy of NASA/JPL-Caltech/SwRI/MSSS/Betsy Asher Hall/Gervasio Robles

An unexpected magnetic field was not the only surprise from the first data haul. The mission also provided a first-look at Jupiter’s poles, which are unexpectedly covered in swirling, densely clustered storms the size of Earth.

“We’re puzzled as to how they could be formed, how stable the configuration is, and why Jupiter’s north pole doesn’t look like the south pole,” said Bolton. “We’re questioning whether this is a dynamic system, and are we seeing just one stage, and over the next year, we’re going to watch it disappear, or is this a stable configuration and these storms are circulating around one another?”

Juno’s Microwave Radiometer (MWR) also threw up some surprises, with some of the planet’s belts appearing to penetrate down to its surface, while others seem to evolve into other structures. It’s a curious phenomenon, and one which the scientists hope to better explore on future flybys.

“On our next flyby on July 11, we will fly directly over one of the most iconic features in the entire solar system – one that every school kid knows – Jupiter’s Great Red Spot,” said Bolton.

“If anybody is going to get to the bottom of what is going on below those mammoth swirling crimson cloud tops, it’s Juno and her cloud-piercing science instruments.”

Next-generation spaceplane: DARPA and Boeing to make on-demand space launches a reality by 2020s

DARPA has taken a major step towards the creation of a new class of hypersonic aircraft that would offer low-cost, short-notice space launches, with the selection of The Boeing Company as its design partner.

Having already developed initial designs for the next-generation spaceplane, known as Experimental Spaceplane or XS-1, Boeing will now be tasked with completing detailed working designs, fabricating the craft and performing flight tests. The vehicle will be constructed and tested by 2019, before embarking on between 12 and 15 test flights in 2020.

Once completed, the plane will represent a major step forward in accessing space, allowing launches to be enacted within a matter of days, rather than the current timescale of months or years, and at a cost far lower than is currently the case.

“The XS-1 would be neither a traditional airplane nor a conventional launch vehicle but rather a combination of the two, with the goal of lowering launch costs by a factor of ten and replacing today’s frustratingly long wait time with launch on demand,” said Jess Sponable, DARPA program manager.

Designed to be completely re-useable, the unmanned XS-1 is around the same size as a business jet, and would take off vertically like a traditional rocket.

However, unlike a traditional rocket, it would require no external boosters to launch, instead being powered entirely by self-contained cryogenic propellants. Once the XS-1 arrived in subortbit, a booster would release a one-use upper stage to deploy the payload: a satellite, before the craft itself returned to Earth, landing horizontally like an aircraft.

Upon landing, the craft would be prepped for the next launch, and would be available to blast off again within a matter of hours. It is hoped that it will cut the cost of launch to below $5m per launch with frequent flights.

“We’re delighted to see this truly futuristic capability coming closer to reality,” said Brad Tousley, director of DARPA’s Tactical Technology Office (TTO).

“Demonstration of aircraft-like, on-demand, and routine access to space is important for meeting critical Defense Department needs and could help open the door to a range of next-generation commercial opportunities.”

Images courtesy of DARPA

Now Boeing has been selected to move forward with the spaceplane, it will face a very short timeframe in which to complete a working craft.

“We’re very pleased with Boeing’s progress on the XS-1 through Phase 1 of the program and look forward to continuing our close collaboration in this newly funded progression to Phases 2 and 3—fabrication and flight,” said Sponable.

From now until 2019, Boeing will be tasked with completing all design work and fabricating the spaceplane, before completing on-the-ground tests. These will require the aircraft to be fired 10 times in 10 days before a launch is attempted.

Once this stage is completed, Phase 3 will be launched, which will see the spacecraft complete between 12 and 15 test flights in 2020.

After these, the XS-1 will be subject to more rigorous flight tests, including 10 flights in 10 days, first without payloads, at speeds up to Mach 5. Eventually the spaceplane will be tested at Mach 10, and will deliver dummy payloads first at a fraction of and then the full weight of a satellite.