On the morning of February 18th, 2020, observers in most of North America will be able to see the waning crescent Moon pass in front of (occult) the planet Mars. The photo at the right, taken by Andrew Chaikin during the 2003 lunar occultation of Mars, is more dramatic than this event will appear through a telescope. In the 2003 occultation, Mars was just 0.48 astronomical units (AU) from the Earth, while this time Mars will be at distance of 1.81 AU, 3.8 times farther away and correspondingly smaller and dimmer. Still, Mars will shine at magnitude 1.2, one of the brightest “stars” in the sky, and its reddish hue will stand out against the colourless Moon.
This map shows the visibility of the occultation. The occultation will be visible in the area delimited by the cyan shape at the top and the multicoloured curve at the bottom. The event will thus be visible in most of North America (except for Alaska and the far north of Canada), Central America, and the Caribbean. In the area of the loop at the top left, covering part of the American northwest and western Canada, the Moon will rise with the occultation already in progress, but observers will be able to see Mars emerge from behind the Moon’s dark limb at its conclusion.... [Read More]
The television series Mars, produced by National Geographic and originally aired on their cable channel in 2016, is a curious mix of present-day documentary and fictional story of the human settlement of Mars, with the first crewed landing mission launching in 2033. The first season is set in the years 2033–2037 and chronicles the establishment of the first settlement and its growth into a fledgling base, similar to scientific research stations in Antarctica. The series cuts back and forth between the present and the fictional future, with the present-day segments interviewing figures such as Stephen Petranek, author of How We’ll Live on Mars, upon which the story is based, Robert Zubrin, creator of the Mars Direct mission plan, Elon Musk of SpaceX, Andy Weir, author of The Martian, and Neil deGrasse Tyson. The mission is mounted by a fictional international consortium called the “International Mars Science Foundation” (IMSF), which has all of the squabbling and politics you’d expect for something with such a name. The fictional part of the first season is pretty good, and in line with capabilities expected to exist in the time in which it is set.
The second season is something else entirely. Set in 2042, it chronicles the arrival of the first private venture on Mars, “Lukrum Industries”, aimed at resource exploration and development. Lukrum has negotiated a deal with IMSF in which it will produce solar mirrors from in-situ resources which will be employed in IMSF’s terraforming project, which hopes to warm the planet to release water trapped as ice below the surface. This veers immediately into the “corporations bad, government agencies (especially multinational ones where all of the minions speak perfect English with suitably exotic accents) good” trope. The present-day segments are almost entirely about human despoliation of the Earth, with a concentration on “climate change”. This feeds into the fictional future story, where the evil corporation (eventually in cahoots with the Russians, who were too tempting to leave out as villains), is simultaneously thwarting the noble goals of the taxpayer-funded scientists, while using its lucre to manipulate IMSF back on Earth to acquiesce in its evil schemes.... [Read More]
Fifty years ago, with the successful landing of Apollo 11 on the Moon, it appeared that the road to the expansion of human activity from its cradle on Earth into the immensely larger arena of the solar system was open. The infrastructure built for Project Apollo, including that in the original 1963 development plan for the Merritt Island area could support Saturn V launches every two weeks. Equipped with nuclear-powered upper stages (under active development by Project NERVA, and accommodated in plans for a Nuclear Assembly Building near the Vehicle Assembly Building), the launchers and support facilities were more than adequate to support construction of a large space station in Earth orbit, a permanently-occupied base on the Moon, exploration of near-Earth asteroids, and manned landings on Mars in the 1980s.
But this was not to be. Those envisioning this optimistic future fundamentally misunderstood the motivation for Project Apollo. It was not about, and never was about, opening the space frontier. Instead, it was a battle for prestige in the Cold War and, once won (indeed, well before the Moon landing), the budget necessary to support such an extravagant program (which threw away skyscraper-sized rockets with every launch), began to evaporate. NASA was ready to do the Buck Rogers stuff, but Washington wasn’t about to come up with the bucks to pay for it. In 1965 and 1966, the NASA budget peaked at over 4% of all federal government spending. By calendar year 1969, when Apollo 11 landed on the Moon, it had already fallen to 2.31% of the federal budget, and with relatively small year to year variations, has settled at around one half of one percent of the federal budget in recent years. Apart from a small band of space enthusiasts, there is no public clamour for increasing NASA’s budget (which is consistently over-estimated by the public as a much larger fraction of federal spending than it actually receives), and there is no prospect for a political consensus emerging to fund an increase.... [Read More]
NASA’s Mars InSight lander is now approaching the Red Planet and will attempt to land later today. Here is a timeline of events during the entry, descent, and landing (EDL) phase if everything goes as planned (adapted from the NASA/JPL “Landing Milestones” page). All times are in Universal Time (UTC), which you can see in the title bar at the top of the Ratburger page.
19:40 UTC – Separation from the cruise stage that carried the mission to Mars
19:41 UTC – Turn to orient the spacecraft properly for atmospheric entry
19:47 UTC – Atmospheric entry at about 19,800 kilometres per hour, beginning the entry, descent and landing phase
19:49 a.m.UTC – Peak heating of the protective heat shield reaches about 1,500 °C
15 seconds later – Peak deceleration, with the intense heating causing possible temporary dropouts in radio signals
19:51 UTC – Parachute deployment
15 seconds later – Separation from the heat shield
10 seconds later – Deployment of the lander’s three legs
19:52 UTC- Activation of the radar that will sense the distance to the ground
19:53 UTC – First acquisition of the radar signal
20 seconds later – Separation from the back shell and parachute
0.5 second later – The retrorockets, or descent engines, begin firing
2.5 seconds later – Start of the “gravity turn” to get the lander into the proper orientation for landing
22 seconds later – InSight begins slowing to a constant velocity (from 27 km/h to a constant 8 km/h) for its soft landing
19:54 UTC – Expected touchdown on the surface of Mars
20:01 UTC- “Beep” from InSight’s X-band radio directly back to Earth, indicating InSight is alive and functioning on the surface of Mars
No earlier than 20:04 UTC, but possibly the next day – First image from InSight on the surface of Mars
Here is a description of the entry, descent, and landing phase.... [Read More]