The Astronomy Thread

meStevo · Jan 19, 2017

Yeah, they showed it from before the boost-back burn all the way to touchdown, very few frames lost. Was pretty awesome.

Ukerric · Jan 20, 2017

Trump + Musk (twice now) = Mars 2024?

If he gets reelected, that'd be the crowning moment of his presidency.

1987 · Jan 21, 2017

Tuco said:
What resources does the moon have you could make fuel with?

Didnt we discover water ice on the moon within the last few years. I thought it was contained within polar craters that basically never had an angle that would recveive sunlight and thus wouldnt be subject to evaporation. And since water is H2O, the hydrogen would be available to make the slush-hyrdrogen propellant many modern rockets run on.

Lunar water - Wikipedia
"In November 2009, NASA re-confirmed water on moon with its LCROSS space probe which detected a significant amount of hydroxyl group in the material thrown up from a south polar crater by an impactor;[10] this may be attributed to water-bearing materials[11] – what appears to be "near pure crystalline water-ice".[12] In March 2010, it was reported that the Mini-SAR on board Chandrayaan-1 had discovered more than 40 permanently darkened craters near the Moon's north pole that are hypothesized to contain an estimated 600 million metric tonnes (1.3 trillion pounds) of water-ice.[12][13]"

Big Phoenix · Jan 22, 2017

Well unless you plan on building your moonbases at the poles, it would require significant amounts of infrastructure to make use of.

Ukerric · Jan 23, 2017

Big Phoenix said:
Well unless you plan on building your moonbases at the poles, it would require significant amounts of infrastructure to make use of.

Given the thermal variation between night and day, the poles are almost certainly among the best locations for any permanent base.

Take a lunar telescope, for instance. It's the easiest "use case" for lunar bases: you get the advantages of a ground-built telescope (large base, maintenance) and the advantages of a space telescope (no atmospheric distortions). Building it on the earth-facing side is stupid, you have this large and bright object permanently in the sky. Building it on farside is better, but you still have 15 days per month where the other large and bright object (the sun) interferes. A polar telescope in a crater is protected from both glares. But, alas, it can observe only half of the sky, whereas the entire sky is visible from the farside over the year.

meStevo · Jan 23, 2017

NASA's latest GOES sat is up and running, first images here: GOES-16 Data and Imagery

I like this moon shot they captured from geo-sync orbit. Apparently they use the moon to help w/ calibration.

Dandain · Jan 25, 2017

Direct Imaging of Exoplanets.

This evocative movie of four planets more massive than Jupiter orbiting the young star HR 8799 is a composite of sorts, including images taken over seven years at the W.M. Keck observatory in Hawaii. The movie clearly doesn’t show full orbits, which will take many more years to collect. The closest-in planet circles the star in around 40 years; the furthest takes more than 400 years. But as described by Jason Wang, an astronomy graduate student at the University of California, Berkeley, researchers think that the four planets may well be in resonance with each other. In this case it’s a one-two-four-eight resonance, meaning that each planet has an orbital period in nearly precise ratio with the others in the system. The black circle in the center of the image is part of the observing and analyzing effort to block the blinding light of the star, and thus make the planets visible.

Source:
A Four Planet System in Orbit, Directly Imaged and Remarkable – Many Worlds

meStevo · Jan 25, 2017

Holy shit that's awesome.

spronk · Jan 25, 2017

damn that is pretty fucking dope. didn't expect shit like that so fast

A Brilliant Green Meteor Lights Up India’s ‘Sky Islands’
IT IS REALLY hard to photograph a meteor. Even though some 25 million of them hurtle toward Earth each day, most of them are too small to track. Those you can see are tough to spot during the day, and most people are sleeping when they streak across the sky at night. But Prasenjeet Yadav managed to get one anyway, entirely by accident.

Yadav was asleep when this bright green meteor exploded over Mettupalayam, a small town in the mountainous Western Ghats region of southern India. But the time-lapse rig he’d set up on a nearby hilltop captured this beautiful image.