Amazon billionaire Jeff Bezos is showing off a picture of his Blue Origin space venture’s BE-4 rocket engine going full blast during a hot-fire test in Texas. “BE-4 continues to rack up time on the test stand,” Bezos said in an accompanied by a picture of today’s full-power engine test. A post shared by (@jeffbezos) on Aug 2, 2019 at 8:24pm PDT Getting the BE-4 into operation is crucial to Blue Origin’s space ambitions. The rocket engine, which runs on liquefied natural gas and packs 550,000 pounds of thrust at liftoff, is destined for use on Blue Origin’s orbital-class New Glenn rocket. It’s also . Both those rockets are currently scheduled to have their maiden launches in 2021. Bezos’ company tends to play its cards closer to the vest than rival billionaire Elon Musk’s SpaceX, which has been letting its fans pass along and Starship hops in South Texas over the past few months. Blue Origin has been testing BE-4 engine components at its West Texas proving ground for more than two years, and the course has not always run smooth. In May 2017, for instance, , resulting in the loss of hardware. The fact that he’s sharing a picture of the full-power firing on a summery Friday night suggests that the test program is on track. But it also suggests there are more test firings to go. Bezos has said more than once that he’s annually. Just in the past few days, Bezos , and it’s a sure bet that some of that cash is going toward the BE-4. When the BE-4 gets an honest-to-goodness thumbs-up, that’ll clear the way for engine production to shift from Blue Origin’s headquarters in Kent, Wash., to a in Huntsville, Ala. That, in turn, will set the stage for New Glenn rocket assembly to move ahead at Blue Origin’s . Bottom line? Keep an eye on and for word that the BE-4 has passed its final test.
August 02, 2019
An artist’s conception depicts GJ 357 d orbiting its host star. (Cornell University Illustration / Jack Madden) Astronomers are sharing a flood of findings from NASA’s Transiting Exoplanet Survey Satellite, or TESS, including the detection of a potentially habitable super-Earth far beyond our solar system. The planet is said to circle an M-type dwarf star called GJ 357, about 31 light-years from Earth in the constellation Hydra. Known as GJ 357 d, the world is at least six times more massive than Earth — and orbits the star every 55.7 days, at a distance that’s only 20% as far away as Earth is from our own sun. With that orbit, GJ 357 d would be broiling-hot if it were in our solar system. But its parent star is so much dimmer than our sun that the super-Earth could conceivably be just warm enough to have liquid water. That characteristic serves as the definition for habitable zones around alien suns. “This is exciting, as this is humanity’s first nearby super-Earth that could harbor life – uncovered with help from TESS, our small, mighty mission with a huge reach,” astronomer Lisa Kaltenegger, who’s the director of Cornell University’s Carl Sagan Institute, . The findings relating to the GJ 357 system are detailed in research papers published by the journal and the . Detecting GJ 357 d was a complex operation. It started with data from the TESS satellite, which was and scans the skies for the telltale signs of planets crossing in front of their parent stars. The same transit-tracking technique was used by to identify thousands of candidate planets. TESS’ readings indicated that the dwarf star harbored a super-close-in planet dubbed GJ 357 b, which makes a complete orbit in just 3.9 Earth days. Assuming that the planet lacks an atmosphere, scientists estimated GJ 357 b’s equilibrium temperature to be in the range of 490 degrees Fahrenheit (254 degrees Celsius). “We describe GJ 357 b as a ‘hot Earth,’ ” Enric Pallé, an astrophysicist at the , said in a . “Although it cannot host life, it is noteworthy as the third-nearest transiting exoplanet known to date and one of the best rocky planets we have for measuring the composition of any atmosphere it may possess.” To get a better fix on the toasty planet, astronomers turned to ground-based observations. Those observations were analyzed using a different method, which measures the ever-so-slight wobbles in a star’s position caused by the gravitational tug of its planets. In addition to confirming GJ 357 b’s existence, the analysis determined that two other planets orbited the star in farther-out orbits. One was GJ 357 c, a too-hot planet that’s at least 3.4 times as massive as Earth and orbits the star every 9.1 days. The other was GJ 357 d. If GJ 357 d lacks an atmosphere, its equilibrium temperature would be uncomfortably chilly, around 64 degrees below zero F (-53 degrees C). But if it has an atmosphere, as expected for a rocky planet at that distance, temperatures would be more moderate — and the prospects for life would be much sunnier. “With a thick atmosphere, the planet GJ 357 d could maintain liquid water on its surface like Earth, and we could pick out signs of life with telescopes that will soon be online,” Kaltenegger said. The studies about GJ 357 and its planets were published in conjunction with the , conducted this week at MIT in Cambridge, Mass. The TESS mission is led and operated by MIT, and managed by NASA’s Goddard Space Flight Center. More than a dozen other partners contribute to the mission. Earlier in the week, the TESS team reported the detection of three exoplanets circling TOI 270, another M-type dwarf star that’s about 73 light-years away in the constellation Pictor. (For what it’s worth, TOI stands for “TESS Object of Interest.”) The innermost planet, TOI 270 b, appears to be a hot super-Earth that’s similar to GJ 357 b. In a scientists say the other two planets, TOI 270 c and d, are about half the size of Neptune — and are likely to be similar to that gas giant in composition. Such “mini-Neptunes” don’t exist in our solar system. “An interesting aspect of this system is that its planets straddle a well-established gap in known planetary sizes,” said Fran Pozuelos, a postdoctoral researcher at the University of Liège in Belgium. “It is uncommon for planets to have sizes between 1.5 and two times that of Earth for reasons likely related to the way planets form, but this is still a highly controversial topic,” Pozuelos . “TOI 270 is an excellent laboratory for studying the margins of this gap and will help us better understand how planetary systems form and evolve.” All this is just the start: TESS’ primary mission is due to last another year, and the data analysis could go on for years longer. In addition to Pozuelos, the authors of the Nature Astronomy paper, are Maximilian Günther and Ian Waite. Pallé and Kaltenegger are among 76 authors of the Astronomy & Astrophysics paper, Principal author is Rafael Luque. In addition to Kaltenegger, Luque and Pallé, the authors of the paper in the Astrophysical Journal Letters, include Jack Madden, Zifan Lin, Sarah Rugheimer, Antigona Segura and Néstor Espinoza.
July 31, 2019
This image was taken during the LightSail 2 sail deployment sequence on July 23. Baja California and Mexico are visible in the background. This image has been de-distorted and color corrected. (Planetary Society Photo / CC BY-NC 3.0) It may be “mission accomplished” for the , but its privately funded LightSail 2 mission is far from over. Five weeks after LightSail 2’s launch aboard a SpaceX Falcon Heavy rocket, the nonprofit membership society celebrated the spacecraft’s ability to raise the highest point of its orbit by a little more than a mile (1.7 kilometers), using the force of sunlight pressing against its 18.4-foot-wide, 4.5-micron-thick reflective Mylar sails. Demonstrating solar sail steerability was the point of the decade-long campaign to build and fly LightSail 2 and its predecessor, . The project’s estimated $7 million cost was covered by contributions from Planetary Society members and other donors. “On behalf of the tens of thousands of people around the world who came together to help the dream of solar sailing move forward, we’re thrilled to declare mission success for LightSail 2,” Planetary Society chief scientist Bruce Betts, who serves as program manager for LightSail, told journalists today at a teleconference. The sail maneuvered itself in response to commands beamed up from Earth to take advantage of the push of the sun’s photons, in a way that’s similar to what sailboats do when they take advantage of the wind. LightSail 2 isn’t the first solar sail to get a push from the sun: That distinction belongs to Japan’s Ikaros spacecraft, which in 2010. But the Planetary Society’s executive director, Bill Nye (the Science Guy), said LightSail 2 showed that the job could be done using a 3U CubeSat spacecraft that’s about the size of a loaf of bread. This image was taken during the LightSail 2 sail deployment sequence on July 23. The sail is almost fully deployed here and appears warped near the edges due to the spacecraft’s 185-degree fisheye camera lens. The image has been color corrected and some of the distortion has been removed. The sun is visible at center. (Planetary Society Photo / CC BY-NC 3.0) If the technology can be perfected, solar sailing could be suitable for a wide range of fuel-free space applications — for example, keeping spacecraft steady above Earth’s poles or at gravitational balance points in deep space. Sail-borne spacecraft could also be directed from one solar system destination to another, or out of the solar system altogether. Nye said his favorite solar sailing destination would be the planet next door. “We’d ferry cargo to Mars and look for signs of life, and change the course of human history. How about that?” he said. Nye noted that the late astronomer Carl Sagan, one of the Planetary Society’s co-founders, promoted the idea of using a solar sail to send a spacecraft to Comet Halley back in the 1970s. Sagan happened to be one of Nye’s mentors. “I’ve been charmed or thrilled by this idea ever since I heard about it 40 years ago,” Nye said. LightSail 2 a week ago, after a series of orbital checkouts. Purdue aerospace engineer David Spencer, LightSail 2’s mission manager, said the orbit was raised in a series of steps. The biggest step lifted the spacecraft a little more than 900 meters (half a mile). Spencer said LightSail 2’s capabilities would undergo further testing during maneuvers that are due to continue through August. But there’s a limit: Every time there’s a rise in the maximum altitude of LightSail 2’s elliptical orbit (known as the apogee) there’s a corresponding drop in the minimum altitude on the other side of the orbit (known as the perigee). “For simplicity, the plan was never to circularize the orbit, only to raise apogee by thrusting on one side of the orbit, which also drops perigee,” the Planetary Society’s Jason Davis . Years of computer simulations. Countless ground tests. They've all led up to now. The Planetary Society's crowdfunded LightSail 2 spacecraft is successfully raising its orbit solely on the power of sunlight. Details at — Planetary Society (@exploreplanets) Eventually, the atmospheric drag at perigee will cancel out LightSail 2’s orbit-raising capability and pull it back toward Earth. The Planetary Society expects the spacecraft to meet its downfall in less than a year. But before it burns up, Spencer wants to do a final experiment. “Once we get down to the point of re-entry, I’d like to see if we can actually control the re-entry point somewhat by changing the orientation of the solar sail,” he told GeekWire. “That’s an experiment that, to my knowledge, hasn’t been done before.” There’s more solar sailing on the horizon: NASA plans to put a solar sail on , an asteroid-observing mission that’s due for launch as a secondary payload on the. “The NEA Scout engineers have been working with us,” Spencer said. Meanwhile, the Planetary Society is planning a competition to select its next crowdfunded space mission. “We are involved in other, we believe, game-changing technologies for planetary exploration,” Nye said. As an example, he pointed to the society-supported , which would stir up a sampling of soil from the lunar surface and capture it for chemical analysis. “This international formal proposal competition is what we’re doing next,” he said.
July 31, 2019