A stunning new photograph from the Hubble Space Telescope shows a nearly perfect Einstein Ring, an effect caused by gravitational lensing. This is one of the most complete Einstein Rings ever seen.
Continue reading “What a Perfect Gravitational Lens”Webb’s Testing is Complete. Now it Begins the Journey to the Launch Site.
Finally, it’s starting to get real for the James Webb Space Telescope. Engineers are now preparing the long-awaited landmark telescope for transport to its launch site at Europe’s Spaceport in French Guiana.
Continue reading “Webb’s Testing is Complete. Now it Begins the Journey to the Launch Site.”An Asteroid has Been Discovered That Crosses Mercury’s Orbit
Astronomers have spotted the fastest-ever asteroid orbiting Sun — and at times, it gets closer to the Sun than the planet Mercury.
Continue reading “An Asteroid has Been Discovered That Crosses Mercury’s Orbit”Watch: 14 Hours of Enceladus Geyser Action
What a parting gift the Cassini mission gave us.
Below is a movie sequence of images, garnered from the final dedicated observation of the Enceladus’ geysers by the imitable Cassini spacecraft.
Continue reading “Watch: 14 Hours of Enceladus Geyser Action”Japan’s Mission to Phobos Will Also Bring a Sample Home by 2029
Japan’s space agency (JAXA) is gearing up for its Martian Moons eXploration (MMX) mission, with plans to have a sample from Mars’ moon Phobos return to Earth by 2029. Mission scientists say they hope to find clues to the origins of Mars two moons, as well as Mars itself, and possibly even traces of past life.
“We think that the Martian moon, Phobos, is loaded with material lifted from Mars during meteorite impacts,” the MMX team said on Twitter. “By collecting this Phobos sample, MMX will help investigate traces of Martian life and the new era of Martian habitability exploration in the 2020s will begin.”
Continue reading “Japan’s Mission to Phobos Will Also Bring a Sample Home by 2029”Ingenuity’s Flight 12 was a Tricky one, Flying Over Hazardous Terrain
The Ingenuity helicopter on Mars has now completed its 12th flight, where it acted as a scout, looking ahead for dangerous terrain for it’s partner in crime, the Perseverance rover.
Continue reading “Ingenuity’s Flight 12 was a Tricky one, Flying Over Hazardous Terrain”Can you Last a Year on Mars? NASA is Recruiting Crew for a Year-Long Analog Mission
Want to try living on Mars, but not sure you want to experience the nine-month flight time to get there? NASA is looking for applicants to serve as crew members for a one-year analog mission in a habitat to simulate life on the Red Planet, beginning in Fall 2022. All you have to do is get to Houston, Texas, and you’ll even get paid.
Continue reading “Can you Last a Year on Mars? NASA is Recruiting Crew for a Year-Long Analog Mission”The First Images and Videos from the Double Venus Flyby
Two spacecraft made historic flybys of Venus last week, and both sent back sci-fi-type views of the mysterious, cloud-shrouded planet.
The Solar Orbiter and BepiColombo spacecraft both used Venus for gravity assists within 33 hours of each other, capturing unique imagery and data during their encounters.
Continue reading “The First Images and Videos from the Double Venus Flyby”OSIRIS-Rex got to Know Bennu Really Well. Apparently, There’s now a 1-in-1,750 Chance That it’ll hit Earth by 2300
Asteroid Bennu is one of the two most hazardous known asteroids in our Solar System. Luckily, the OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer) spacecraft orbited Bennu for more than two years and gathered data that has allowed scientists to better understand the asteroid’s future orbit, trajectory and Earth-impact probability, and even rule out some future impact possibilities.
In the most precise calculations of an asteroid’s trajectory ever made, researchers determined Bennu’s total impact probability through the year 2300 is really small — about 1 in 1,750 (or 0.057%). The team’s paper says the asteroid will make a close approach to Earth in 2135, where Bennu will pose no danger at that time. But Earth’s gravity will alter the asteroid’s path, and the team identifies Sept. 24, 2182 as the most significant single date in terms of a potential impact, with an impact probability of 1 in 2,700 (or about 0.037%).
“The impact probability went up just a little bit, but it’s not a significant change,” said Davide Farnocchia, lead author of the paper, and scientist at the Center for Near Earth Object Studies at NASA’s Jet Propulsion Laboratory, speaking at a press briefing this week. Farnocchia added that means there is a 99.94% probability that Bennu is not on an impact trajectory.
“So, there is no particular reason for concern,” he said. “We have time to keep tracking the asteroid and eventually come to a final answer.”
101955 Bennu was discovered in 1999 by the Lincoln Near-Earth Asteroid Research Team. Since its discovery, Bennu has been extensively tracked with 580 ground-based optical astrometric observations. The asteroid made three relatively close passes of Earth in 1999, 2005, and 2011, during which the Arecibo and Goldstone radar stations collected a wealth of data about Bennu’s motion.
But OSIRIS-REx’s two-year reconnaissance and sample collection has provided crucial data about the 500-meter-wide asteroid, including some surprises. Scientists expected Bennu’s surface to be smooth and sandy, but the first images from OSIRIS-REx revealed a rugged boulder-field, littered with large rocks and loose gravel. The team also expected the asteroid to be geologically quiet, but just six days after arriving in orbit, the spacecraft observed the asteroid ejecting bits of rock, due to rocks on the asteroid cracking because of the day-night heat cycle. We also learned that Bennu has pieces of Vesta on it. The spacecraft also scooped up a sample of rock and dust from the asteroid’s surface in October of 2020, which it will deliver to Earth on Sept. 24, 2023, for further scientific investigation.
But OSIRIS-REx’s precise observations of Bennu’s motions and trajectory allowed for the best estimate yet of the asteroid’s future path.
“The OSIRIS-REx mission has provided exquisitely precise data on Bennu’s position and motion through space to a level never captured before on any asteroid,” said Lindley Johnson, planetary defense officer at NASA’s Planetary Defense Coordination Office at NASA.
The researchers took into account all kinds of small influences, including the tiny gravitational pull of more than 300 other asteroids, and the drag caused by interplanetary dust. They even checked to see if OSIRIS-REx pushed the asteroid off course when the spacecraft briefly touched its rocky surface with its Touch-And-Go (TAG) sample collection maneuver. But that event had a negligible effect, as expected.
The researchers especially focused on a phenomenon called the Yarkovsky effect, where an object in space would, over long periods of time, be noticeably nudged in its orbit by the slight push created when it absorbs sunlight and then re-emits that energy as heat. Over short timeframes, this thrust is minuscule, but over long periods, the effect on the asteroid’s position builds up and can play a significant role in changing an asteroid’s path.
“The Yarkovsky effect will act on all asteroids of all sizes, and while it has been measured for a small fraction of the asteroid population from afar, OSIRIS-REx gave us the first opportunity to measure it in detail as Bennu travelled around the Sun,” said Steve Chesley, senior research scientist at JPL and study co-investigator, in a press release. “The effect on Bennu is equivalent to the weight of three grapes constantly acting on the asteroid – tiny, yes, but significant when determining Bennu’s future impact chances over the decades and centuries to come.”
They also were able to better determine how the asteroid’s orbit will evolve over time and whether it will pass through a “gravitational keyhole” during its 2135 close approach with Earth. These keyholes are areas in space that would set Bennu on a path toward a future impact with Earth if the asteroid were to pass through them at certain times, due to the effect of Earth’s gravitational pull.
The team wrote in their paper that “compared to the information available before the OSIRIS-REx mission, the knowledge of the circumstances of the scattering Earth encounter that will occur in 2135 improves by a factor of 20, thus allowing us to rule out many previously possible impact trajectories.”
“The orbital data from this mission helped us better appreciate Bennu’s impact chances over the next couple of centuries and our overall understanding of potentially hazardous asteroids – an incredible result,” said Dante Lauretta, OSIRIS-REx principal investigator and professor at the University of Arizona. “The spacecraft is now returning home, carrying a precious sample from this fascinating ancient object that will help us better understand not only the history of the solar system but also the role of sunlight in altering Bennu’s orbit since we will measure the asteroid’s thermal properties at unprecedented scales in laboratories on Earth.”
Further reading:
Paper published in Icarus
NASA press release
Want a LEGO James Webb Space Telescope? It Even Folds Up
As we all anticipate the launch of the James Webb Space Telescope (JWST) later this year (hopefully), LEGO designers are hoping for a “launch” of their own. A new LEGO design of JWST is currently gathering supporters on the LEGO Ideas website. If it gets enough support, LEGO will review it and possibly create it.
As of today (August 12, 2021), the idea has just under 1,500 supporters, with the goal of 10,000. If you want your very own JWST model, cast your vote of support!
Continue reading “Want a LEGO James Webb Space Telescope? It Even Folds Up”