Author: jappe

Credit: NRAO

This view of Mercury is made up of hundreds of images taken by NASA’s MESSENGER spacecraft during its first flyby of the planet in 2008. New data suggest that Mercury, the closest planet to the sun, completes a rotation on its axis 9 seconds more quickly than previously thought. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington/DLR

Mercury is a spinning faster than scientists had thought: New research shows that the planet completes a rotation on its axis roughly 9 seconds more quickly than scientists previously charted — and that data will help scientists understand more about the planet’s molten core.

Mercury is a rocky planet only slightly larger than Earth’s moon. Based on the data collected from NASA’s MESSENGER spacecraft, scientists think most of Mercury contains a molten core that takes up 70 percent of the planet’s mass. The newly measured rotation rate can be used to help calculate the proportions of solid and liquid within, even as researchers begin to understand its cause.

“One possible explanation for Mercury’s faster rotation is that Jupiter influences its orbit,” study participant Alexander Stark, of the German Space Agency (DLR) Institute of Planetary Research, said in a statement. “As a result, its distance from the sun varies, which, in turn, affects the planet’s rotation speed.” [Planet Mercury: Simple Facts, Tough Quiz]

Mercury is the closest planet to the sun. Because of tidal forces exerted by the star’s gravity, Mercury has a 59-day rotation period that represents a 3:2 ratio with its 88-day orbit around the sun — for every three times it rotates, it orbits the sun twice. This ratio is unique among planets in the solar system.

MESSENGER (Mercury Surface, Space Environment, Geochemistry and Ranging) was the first orbital mission around Mercury; after flying by the planet a couple of times, it remained there taking measurements between 2011 and 2015. 

While it was there, MESSENGER was also the first spacecraft to detect slight irregularities as Mercury moved around its orbit. By measuring the irregularities, scientists can deduce the size and density of the core, as well as map the planet more accurately.

MESSENGER measured the altitude of the surface by timing the reflection of laser pulses off of the planet. These data were then compared with terrain models based on photos taken by the spacecraft.

In addition to providing more information about Mercury’s core, the rotation speed allows researchers to make highly accurate maps of the planet’s surface — which officials say will help with future missions to Mercury. In 2017, the European Space Agency plans to launch the BepiColombo mission to further examine the planet’s surface and internal structure.

Follow Elizabeth Howell @howellspace, or Space.com @Spacedotcom. We’re also on Facebook and Google+. Original article on Space.com .

SpaceX has thrown open the hatch to its Crew Dragon spacecraft, revealing a sleek black and white interior for the capsule it is building to fly astronauts to the International Space Station and other destinations.

“Step inside Crew Dragon,” SpaceX invited on a new page of its website on Thursday (Sept. 10).

“Dragon made history in 2012 when it became the first commercial [uncrewed] spacecraft to deliver cargo to the space station,” SpaceX wrote on its website. “But Dragon was also designed from the beginning to carry people, and today SpaceX is finalizing the necessary refinements to make that a reality.” [Take a Video Tour Inside SpaceX’s Crew Dragon Spacecraft]

Images and video newly-released by the company show that the tan leather and mirrored metal surfaces previously unveiled as part of Crew Dragon’s debut in May 2014 have now been replaced by black bucket seats and stark white walls.

SpaceX designed its Crew Dragon manned space capsule to be an enjoyable ride.
Credit: SpaceX

“Crew Dragon was designed to be an enjoyable ride. With four windows, passengers can take in views of Earth, the Moon, and the wider Solar System right from their seats, which are made from the highest-grade carbon fiber and Alcantara cloth,” SpaceX described.

The spacecraft’s only punch of color — other than from its windows — is from the flat panel displays of the capsule’s forward-mounted control panel.

“Crew Dragon’s displays will provide real-time information on the state of the spacecraft’s capabilities, anything from Dragon’s position in space, to possible destinations, to the environment on board,” SpaceX stated.

The Crew Dragon’s environmental control and life support system will “provide a comfortable and safe environment” for its passengers, added the Hawthorne, California-based company. “During their trip, astronauts on board can set the spacecraft’s interior temperature to between 65 and 80 degrees Fahrenheit.”

SpaceX’s Crew Dragon displays will provide real-time information on the state of the spacecraft’s capabilities.
Credit: SpaceX

The fully autonomous Crew Dragon is one of two privately designed spacecraft NASA has contracted to begin flying its astronauts to the space station beginning in 2017. The other, Boeing’s CST-100 Starliner, is also equipped with a primarily black and white cabin, punctuated by the glow of “Boeing Sky Interior” blue LED lighting, as the aerospace company has deployed on its passenger jetliners.

SpaceX, which earlier this year tested the Crew Dragon’s emergency escape system, is planning another abort test in 2017, preceded by a test flight without astronauts to the space station. The company’s first Crew Dragon to fly with NASA astronauts aboard will follow the in-flight abort test, prior to SpaceX starting to fly operational missions to the orbiting outpost in the next two to three years.

Step into SpaceX’s Crew Dragon: watch a video tour inside the capsule at collectSPACE.

Follow collectSPACE.com on Facebook and on Twitter at @collectSPACE. Copyright 2014 collectSPACE.com. All rights reserved.

An ALMA image of the young star HL Tau and the disk of gas and dust surrounding it. New evidence suggests this is the first image ever obtained of planetary birth. Credit: ALMA (NRAO/ESO/NAOJ); C. Brogan, B. Saxton (NRAO/AUI/NSF)

A controversial space image does indeed show the first picture of planets being born, a new study confirms.

When an image of the system HL Tau was unveiled last year, it sparked controversy over whether or not grooves in the disk of dust surrounding the star could be explained by the presence of newly formed giant planets. Now, a new paper suggests that the orbit of those planets could serve to stabilize rather than eject one another, as had originally been suggested. That means this image is the first time scientists have observed a forming planetary system, and a tightly packed one at that.

“The big question is, are we really seeing giant planets carving out the disk out of which they are forming?” lead author Daniel Tamayo, from the University of Toronto in Canada, had said in a presentation at the Emerging Researchers for Exoplanet Science Symposium hosted at Pennsylvania State University in April.

The new research performed by Tamayo and his colleagues provides strong evidence that the answer is yes. [Video: Planet birth around the star HL Tau]

Special orbits

In October 2014, the Atacama Large Millimeter/submillimeter Array (ALMA) — a giant radio telescope in Chile — captured a puzzling image of HL Tau. Scientists immediately began debating whether planets were responsible for carving the gaps in the system, which lies about 450 light-years from Earth, in the constellation Taurus. Although they didn’t take the original ALMA image, Tamayo and his colleagues set out to investigate whether planets could survive so close to one another.

Planets massive enough to carve the close-fitting gaps at the outer edges of the disk would have enough gravity to scatter other close-orbiting neighbors, Tamayo said. When his team ran simulations with planets five times as massive as Saturn, things became eccentric, and at least one of the planets wound up ejected.

However, Tamayo and his colleagues noticed something interesting about the outermost lanes.

“These outer three gaps, the ones that are closest to one another, their locations are close to where you’d have a chain of 4:3 resonance,” Tamayo said.

In a 4:3 resonance, one planet would orbit the star four times for every three times its neighbor traveled around the star. These special orbits would just miss one another, allowing the entire system to remain stable over time. In Earth’s solar system, the presence of a similar orbit allows Pluto to travel inside of Neptune’s orbit but keeps the two from colliding.

In its initial findings, the team argued that the resonances of the outer planets would keep their orbits elliptical. However, if these orbits were not resonant, the disk of gas and dust would make the orbits more circular. Soon after the original findings were published, the scientists who took the original image announced that the gaps were, indeed, elliptical.

“I think that’s really promising evidence that planets are what’s responsible for these gaps,” Tamayo said.

Still, he cautioned, “It’s not a slam dunk.”

However, a system of matched-orbit giants has interesting implications, he said.

“If these are giant planets resonantly interacting, this is the most closely packed system of giant planets,” Tamayo said.

The results were published in the Astrophysical Journal.

‘A ticking time bomb’

A system of close-orbiting massive planets may be stable today, but Tamayo and his colleagues questioned how it could have wound up that way.

“It sets up a puzzle, and that’s the puzzle of formation,” Tamayo said.

He described the special orbits as a cozy shelter, surrounded by a ring of fire of instability.

“How do you slowly migrate across this ring of fire to get to this nice, cozy shelter?” he wondered.

“It seems like we’re in a jam.”

Massive exoplanets would be unlikely to move together without getting kicked out by one another’s gravity. But the scientists realized that smaller planets had the advantage. If the planets were captured into resonance at lower mass, they would avoid the instability issue. Slowly, these smaller planets could grow together into bodies large enough to clear gaps in the cloud of dust surrounding the star.

Tamayo and his team started with planets roughly five times the size of Earth. Their models showed that the smaller protoplanets could form and move into stabilizing orbits without knocking each other out of the young system. Over time, the merged bodies would continue to accrete the gas and dust while in their special orbits, clearing out their own paths as they grew into massive planets roughly the mass of Saturn.

But the system can only remain stable so long, Tamayo said. Eventually, the planets will accrete enough mass that they will bump each other out of resonance, knocking the system out of control, he said.

“This system is a ticking time bomb,” Tamayo said.

Follow Nola Taylor Redd on Twitter @NolaTRedd. Follow us @Spacedotcom, Facebook or Google+. Originally published on Space.com.

WASHINGTON – Rocket engine maker Aerojet Rocketdyne has offered to buy launch services provider United Launch Alliance from Lockheed Martin and Boeing for at least $2 billion, an industry source told SpaceNews Sept. 8.

The unsolicited bid is the latest twist in what has been a topsy-turvy year for ULA, the primary U.S. government launch services provider.

The proposal is still in discussion, but an announcement could come as early as the week of Sept. 14 at the annual U.S. Air Force Association conference, to be held at National Harbor, Maryland, the source said. [Awesome Atlas V Rocket Launch Photos]

Aerojet Rocketdyne’s bid starts at $2 billion, but could go higher after the company does its due diligence, the source said.

Denver-based ULA operates and owns the production rights for the Atlas V and Delta IV rockets, which together launch the vast majority of U.S. government payloads. The Boeing-Lockheed Martin joint venture, established in 2006, also owns a rocket production plant in Decatur, Alabama, and launch infrastructure at Cape Canaveral Air Force Station in Florida and at Vandenberg Air Force Base in California.

ULA faces an uncertain future owing to a congressional ban on the Russian-built RD-180 engine that powers its workhorse, the Atlas V, and a competitive challenge in its government market from upstart SpaceX. Congress appears willing to fund a U.S.-built RD-180 replacement, and Aerojet Rocketdyne is developing one called the AR-1, but ULA last September announced plans to use an alternative built by the secretive Blue Origin rocket company owned by Amazon.com founder Jeff Bezos.

Kent, Washington-based Blue Origin’s planned BE-4 uses a different type of fuel than the RD-180 and as such cannot be retrofitted into the current Atlas V design. ULA, which plans to phase out all but the largest variants of the high-priced Delta IV, in April unveiled a new rocket design called Vulcan that accommodates the BE-4. The new vehicle, to debut around 2020, would essentially be an Atlas 5  outfitted with a new, larger first stage, at least in its initial incarnation.

But Boeing and Lockheed Martin, who control ULA’s purse strings, have yet to agree to invest the roughly $1 billion that ULA says it needs to develop the Vulcan. Blue Origin is funding development of the BE-4, also to the tune of about $1 billion, ULA says.

Spokesmen for Sacramento, California-based Aerojet Rocketdyne, Boeing and Lockheed Martin declined to comment. Jessica Rye, a spokeswoman for ULA, referred questions to Lockheed Martin and Boeing.

In May, a consortium of three companies including Aerojet Rocketdyne asked the U.S. Department of Defense about the possibility of obtaining production rights to  the Atlas V. ULA rebuffed that overture.

A purchase of ULA, if approved by the parent companies and the government, would be a dramatic turnaround for Aerojet Rocketdyne, which was stung by ULA’s decision to go with the BE-4 over the AR-1. ULA continues to fund work on the AR-1, but views that engine as a backup in case Blue Origin falters in its engine effort.

This story was provided by SpaceNews, dedicated to covering all aspects of the space industry.