C omet Atlas is racing toward the inner solar system, and it could become the brightest comet seen in the night sky in over two decades. The comet, discovered by an observatory designed to protect Earth from asteroids, may even be visible during the day just two months from now.
Also known as C/2019 Y4, this comet was discovered by astronomers at the Asteroid Terrestrial-impact Last Alert System (ATLAS) in Hawaii in December 2019. At the time, the comet was exceedingly dim — but the comet became 4,000 times brighter in just a month. This increase is far greater than astronomers predicted, and could potentially signal the comet may soon be exceptionally bright.
NASA may have sidelined the Lunar Gateway for a return mission to the Moon, but it is not stopping the momentum. NASA has awarded several contracts for the Lunar Gateway including the most recent one to SpaceX. This demonstrates the growing capabilities of New Space companies to capture contracts and complete missions.
“This contract award is another critical piece of our plan to return to the Moon sustainably. The Gateway is the cornerstone of the long-term Artemis architecture and this deep space commercial cargo capability integrates yet another American industry partner into our plans for human exploration at the Moon in preparation for a future mission to Mars.”NASA Administrator Jim Bridenstine in a press release statement about the award to SpaceX.
NASA Awarded SpaceX the first Artemis Gateway Logistics Services (GLS) contract. The award for resupply services to the Gateway will require delivery of goods to a Near Rectilinear Halo Orbit (NRHO). Not sure what a NRHO orbit is? A NRHO is a highly elliptical orbit that takes about 7 days for each orbit. Want some more details, just click here: Near Rectilinear Halo Orbit (NRHO). There are a few options for NRHO orbits, but NASA is leaning towards the L2 9:2 lunar synodic resonant southerly Near-Rectilinear Halo Orbit (NRHO) which would be the likely location of the lunar Gateway. A simplification of the orbit is shown below.
To see distant stars and planets, astronomers must first calibrate their equipment to compensate for Earth’s blurry atmosphere — and that’s a whole lot easier said than done. In fact, to pull it off, they have to actually create artificial stars, dubbed ‘guide stars’, using really, really big lasers.
Now, researchers from the European Southern Observatory’s (ESO) Paranal Observatory in Chile have created the most powerful one to date — a system they call the Four Laser Guide Star Facility (4LGSF).
The new system, which has been tested since last September, works by shooting four 29.9-centimetre (11.8-inch), 22-watt beams into the atmosphere to basically mark the sky.
Parachutes are plaguing space programs. SpaceX doesn’t like Parachutes. They are difficult to design, hard to package, and easy to damage. The larger the mass of the spacecraft, the more effort to slow down. Larger, more efficient, complex parachute systems are needed. Several failures have hit the industry over the last few years, including SpaceX Crew Dragon, ESA ExoMars, Boeing CST-100, and the NASA Orion to name a few.
How do parachutes work and why are they hard?
The idea of a parachute is simple. All falling objects fall the same when under the same conditions… that is so long as no outside force is exerted on it. So two objects dropped from the same altitude, one a feather and hammer will fall equally. Don’t believe me? NASA tested it on the Moon. During Apollo 15 moon walk, Commander David Scott performed a live demonstration for the television cameras. Commander Scott did the Apollo 15 Hammer and Feather test. He held out a geologic hammer and a Falcon feather and dropped them at the same time. Because there is not an atmosphere on the Moon, they were essentially in a vacuum. With no air resistance force, the feather fell at the same rate as the hammer. Ironically, Apollo 15 had a second demonstration of falling objects when one of the parachutes failed to function as planned.
Apollo 15 parachute Failure Credit NASA
On Earth, and any other planet with an atmosphere, air acts as a resistance force for an object moving through it. We can get more air resistance force by increasing the surface area. Depending on the shape of the object, it’s orientation, and the amount of resistance will increase, and therefore slow the object down. Unbalanced and uncorrected resistance can cause the object to start to turn, twist and tumble. A parachute system is deployed to generate air resistance from the atmosphere. (note that the thicker the atmosphere the more resistance) Parachutes designed for use on Earth will not be the same as a parachute designed for Mars.
