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Wednesday, December 9, 2020

Fly like an Eagle...but don't land like one

SpaceX Starship prototype SN8 had a (mostly) very successful first high-altitude test flight today, on (mostly) three engines.
Because most of the press today is a bit fixated on the final few seconds of the flight, I'm instead posting a photo from when it was still flying nominally. It was, in all, a very good test flight. And yes, in future flights, SpaceX will certainly improve on the final few seconds of flight as well, because they're also super important.

Saturday, December 5, 2020

Hayabusa2 Returns

Japan's JAXA Hayabusa2 spacecraft has returned with pristine surface samples from the asteroid Ryugu. A cannister from the spacecraft parachuted to southern Australia earlier today.

Thursday, December 3, 2020

Rock On, Chang'e

At 7:10am PST today, China's Chang'e 5 lander lifted off from the moon, bringing back 2 kilograms of rock samples from Oceanus Procellarum. This is the first lunar sample return since the Soviet Luna 24 mission to Mare Crisium in 1976.

Monday, November 30, 2020

Rip van Winkle

Wow. It's been five years since I posted anything here. Did I miss anything?
Yeah, apparently. Crew Dragon has successfully gotten astronauts to the International Space Station and back, the US Navy has confirmed the existence of UFOs, and we went through an entire presidency. And there's a pandemic?
Okay, well, let me get some coffee going, and see where we go from here.

Monday, August 24, 2015

The Darkest Place

The European Space Agency has for about a decade researched the concept of a "hyper telescope," under the name Exo Earth Imager. EEI would be a fleet of 150 orbital 3-meter mirrors, spread across about 8,000 square kilometers of space, and synchronized to reflect and magnify the image of an earth-sized planet in orbit around a distant star, with high enough resolution to discern oceans, continents, forests, deserts and even major river basins. Maintaining the mirrors in their relative orbits with the level of precision needed would be challenging at least. Not insurmountably so, but certainly not trivial.

A possible solution for this is to instead mount the mirrors on a fixed surface. There have already been proposals for building large telescopes on the far side of the moon, shielded from terrestrial radio interference. NASA has even demonstrated that large astronomy-grade mirrors can be constructed in-situ from lunar regolith. A telescope of this scale would have many applications and purposes besides viewing exoplanets, but this would be its primary purpose.

I would like to propose that instead of the lunar far-side, a better location for an optical (and maybe radio as well) telescope would be inside the basin of Peary crater. I've discussed the unique properties of Peary in this blog previously, in the context of human colonization. But briefly, Peary crater, by virtue of being situated on the north pole, has the triple virtue of a basin which is constantly in darkness and protected from solar radiation, a rim that is in constant sunlight for solar power, and a substantial amount of water ice on the floor of the basin. Shackleton crater on the lunar south pole is similar in many respects, and would similarly be an excellent site for this; however Peary is about 80 km in diameter and Shackleton is only about 20 km, so Peary would afford space for a much larger telescope.

Because the basin is always "aimed" at the moon's northern sky, and the same part of the sky is always visible throughout the month and throughout the year, very detailed long-term observations could be made unhindered of this part of the sky. Yes it would be limited to only this part of the sky; however, many space-based telescopes, including NASA's Kepler Space Telescope, have similarly limited fields of view.

And yes, a small astronomical observation outpost and research facility could provide the seed of a human colony in Peary crater as well. In later posts we'll be discussing the advantages of establishing a lunar colony over either Mars, Venus or orbital stations; a moon-based space telescope (at whatever location) could be a very good beginning to a robust lunar city.

Monday, July 13, 2015

Pluto Day!!!

Some of us have been waiting a really long time for the New Horizons flyby of Pluto (it launched almost a decade ago). However, what we are going to see today is basically NOTHING, other than an endless string of NASA press conferences about how they don't have anything to tell or show us.

New Horizons must first be aimed at Pluto (and it's companion planet Charon; apparently NASA has officially stopped calling it a "moon") in order to get photographs and other data during the flyby. Closest point of approach to Pluto will be at 4:49am pdt, but it will continue photographing and collecting data on Pluto for at least several hours after the flyby. Then New Horizons will realign itself to aim its antenna back toward earth. It will first send a short ping to tell the mission team that the spacecraft made it through the Pluto system without mishap, and that the data was collected and is safely in NH's memory banks. This ping will take about four and a half hours to travel from Pluto back to Earth at the speed of light.

Then New Horizons will begin transmitting its preliminary data package. These will include low resolution (about the quality of a JPEG) images of Pluto and Charon during the flyby. Due to the highly attenuated signal crossing some three billion kilometers of interplanetary space, the baud rate of the transmissions will be maddeningly slow. Once received on earth they must be processed and analyzed.

Wednesday (15 July) at noon pdt, NASA will hold a press conference and release the first series of low resolution photos. This is the first new NASA press conference for this mission that will have any real information in it. High resolution photos are forthcoming, but will take about nine months to arrive.