Outer Space

Exploring the final frontier.

New Horizons

Artist depiction.

Today in space exploration…

January 19, 2006, saw the launch of the New Horizons probe. It was the first probe in a program called New Frontiers, that was designed to explore various aspects of the outer solar system. New Horizons is also among the fastest artificial objects ever made, and is the fifth human made object to achieve escape velocity from the solar system.

The primary objective for New Horizons was the enigmatic dwarf planet, Pluto, and it’s frozen companion, Charon. In this respect, New Horizons picked up where the Voyager program left off. Pluto and other objects beyond the orbit of Neptune weren’t included in the Voyager program, though I remember hopeful talk on this point. The Voyager probes made frequent use of gravity assisted slingshot maneuvers around the outer planets to reach their next target. It’s likely that Pluto just wasn’t in a location where a slingshot off one of the ice giants (Uranus or Neptune) would be effective. So, Pluto ultimately had to wait for a dedicated mission.

Pluto

New Horizons was launched at 2:00pm EST (19:00 UTC) from Cape Canaveral, on a rapid trajectory toward the outer solar system. It cleared the Earth-Moon system a mere nine hours after launch. Its first stop was Jupiter, where it received a gravity assisted speed boost from the gas giant, to hasten its journey to the outer solar system.

Charon

New Horizons completed it’s slingshot maneuver around Jupiter on September 4, 2006. While in the Jovian system, the probe took several readings and photographs of Jupiter and its moons, mostly to answer questions raised by previous missions. At the speed it was going it couldn’t do a lot of research, but since it was in the area, why not take a quick look?

Infrared closeup of Jupiter

After barnstorming Jupiter, the probe went into sleep mode for the bulk of its journey. On January 4 of 2015, the first clear images of Pluto were being relayed, and the probe was fully awakened by mission control. At the same time, New Horizons was receiving navigational support from the Hubble telescope back at Earth. Pluto was found to have not one, but a total of five moons. All of them are very small, and along with Pluto they perform a complex square dance around one another. I suspect navigating through such a place would be a nightmare!

The direct flyby of Pluto and its companions occurred in July of 2015, and provided not only excellent photographs of the distant world, but extensive information about atmosphere and geology. Scientists were also provided with insights into the early ages of the solar system, and the nature of the interstellar void. NASA scientists considered all of the primary and secondary objectives, and most of the tertiary objectives, of the Pluto flyby to be a success. The information gathered by New Horizons is still being analyzed today, almost ten year later.

There was a contingency for additional targets for New Horizons, if circumstances permitted. The Kuiper belt is the collective name for a torrid (doughnut) shaped cloud of materials orbiting beyond the orbit of Neptune. There was hope that New Horizons could do a flyby of one of these objects, after visiting Pluto. Again with some help from the Hubble telescope, such a target was located. The Kuiper belt object 486958-Arrokoth was visited by New Horizons on January 1 of 2019, providing even more insight into the nature of the interstellar void, and the various materials within the Kuiper belt.

486958-Arrokoth

Controllers predict that the onboard power cells will allow New Horizons to continue operating until the early 2030’s, so an additional flyby of a Kuiper belt object may be possible. Both the Hubble telescope and the Webb telescope have periodically searched for a suitable and reachable targets. But at this writing, such a target hasn’t been found.

Currently, the craft is collecting data on deep space radiation, heliophysical data, and other characteristics of the Kuiper belt. It has also been conducting long-range observations of two nearby stars, Proxima Centauri and Wolf 359. Most of its instruments are currently in sleep mode, but if a suitable flyby target is located, they can be restarted. New Horizons will exit the Kuiper belt some time in 2028. At that point it will join Pioneer 10, Pioneer 11, Voyager 1 and Voyager 2 in the interstellar void. It should be noted that the two Voyager probes still occasionally send back data, decades after they were expected to shut down. We may continue to hear from New Horizons for many years to come.

Several follow-up missions for the exploration of Pluto have been suggested. While such a mission has not yet been scheduled, the most popular plan under consideration is modeled on the highly successful Cassini-Huygens mission that visited Saturn. It involves a “mother probe” settling into an orbit around Pluto or Charon, and then use the gravity of those two bodies to bounce around the planetoid cluster visiting points of interest. Small drones, or even a lander, would be dispatched along the way.

I suspect distant Pluto and it’s posse of tiny moons still have many stories to tell.

All images are from Wikipedia and Wikipedia Commons.

Friendship 7: Godspeed

Today is the anniversary of a milestone in space exploration, particularly for Americans. On this day in 1962, United States astronaut John Glenn was launched into space on a Mercury-Atlas rocket named Friendship 7. Over a period of just under five hours, Glenn circled the earth three times before splashing down in the North Atlantic.

The iconic phrase “Godspeed, John Glenn,” was said by fellow astronaut M. Scott Carpenter, immediately after launch.

The first human to make a complete orbit of the Earth had been Yuri Gagarin in 1961. Aboard his capsule Vostok 1, Gagarin made one complete orbit of the Earth before returning to earth. The longest manned mission thus far had been Vostok-2, where cosmonaut Gherman Titov made seventeen complete orbits, in August of 1961. The next human to fly in space would be M. Scott Carpenter on Aurora-7, in May of 1962.

John Glenn was a distinguished pilot in both World War II and Korea. After his time with NASA, he went on to serve for 24 years in the United States Senate. This included time on the Senate Foreign Relations Committee and the Senate Governmental Affairs Committee. His political interests included energy policy, nuclear non-proliferation, and environmental issues. He eventually became the oldest man to date to fly in space, when he flew on the space shuttle Discovery during mission STS-95.

He died on December 8, 2016. He had received a heart valve replacement shortly before his death, and his health had been in general decline for much of that year. He was the last surviving member of the Mercury Seven. After laying in state at the Ohio Statehouse, he was laid to rest at Arlington National Cemetery.

The Friendship-7 capsule is on display at the Smithsonian National Air and Space Museum in Washington, DC.

Apollo 8: Christmas at the Moon

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Apollo 8
A depection of Apollo 8’s insertion into lunar orbit, by artist Mark Karvon.

Humanity has staged, to date, nine manned missions to the moon. On six of these missions, people walked on the lunar surface. December 21 is the anniversary of the first trans-lunar launch, and the first manned mission to another celestial body, Apollo 8. Her crew was Frank F. Borman, James A. Lovell, and William A. Anders.

Apollo 8 crew portrait

Apollo 8 was, in many ways, a hardware test. Even as late as 1969, the nature of the lunar surface wasn’t totally understood. The moon was by then known to be covered with a very dusty soil that we now call regolith. There were still doubts about the possibility of landing a human on the moon, the fear being that any lander would sink into the regolith and become trapped as if in quicksand. This was one of the many questions that Apollo 8 was sent to answer. Was the hardware of the Apollo program suitable for the task of sending humans to the moon and back? Observations from the three astronauts, the first humans to get a good, clear view of the lunar surface, concluded that the existing lander design would work.

But as big a question as the lunar surface was, an even bigger question was the navigation of a trans-lunar flight path. Navigating in outer space is very difficult, even when you’re only in Earth orbit. But when you need to deal with not one celestial body, but two, the potential for problems gets very high, very fast. The flight calculations for Apollo 8 were extensive, and needed constant adjustment. But the crew of the spacecraft, and the ground support crew, handled everything in stride. It took Apollo 8 three days to reach the moon. The craft orbited the moon ten times over a roughly eighteen-hour period, then broke orbit for the three day journey home. The return flight began early on Christmas morning, shortly after 6 AM UTC. The craft splashed down on December 27.

The flight of Apollo 8 has been largely overshadowed by the later flight of Apollo 11. But it still had great historical significance. Some of the most famous photographs from the early space program, including the iconic Earthrise, were taken by Apollo 8. It was also the first time that humans had traveled beyond the gravitational influence of Earth. The year 1968 had been riddled with tragedies and turmoil all over the world, but many in the press felt that the success of Apollo 8 allowed the year to end on a relatively high note.

The mission also created some controversy when, during their final television broadcast before leaving lunar orbit, the three astronauts took turns reading the creation story from Genesis. This prompted atheist activist Madalyn Murray O’Hair to sue NASA for having astronauts – government employees – pray on the job. This struck her as violating the separation of church and state. (O’Hair was notorious for doing stuff like that.) The suit was eventually thrown out of court, but NASA did tone down such actions on later flights, wanting to avoid more negative publicity.

The information gathered during the flight of Apollo 8, especially the computation of a trans-lunar round trip, proved vital in the success of the successive manned missions to the moon, including Apollo 11. The command module of Apollo 8 is on display at the Museum of Science and Industry in Chicago, Illinois. Other artifacts from the flight are in museums and science centers around the world.

Venera Seven

venera7
An artist’s portrayal of Venera Seven on the Venusian surface.

Today is another anniversary in space exploration, though not one of the better known ones. This day in 1970 was the first time a vehicle from earth landed on another planet. That vehicle was Venera 7, and it was part of the Soviet Union’s program to explore the planet Venus. The Russians had attempted to send probes to Venus before, but Venera 7 was the first one to successfully reach the planet and send back data.

The craft was launched at Baikonur on August 17 of 1970, and entered a rapid trans-planetary course toward the second planet. It is believed to have reached Venus around December 10 of that year, and the lander portion of the probe entered the atmosphere on the 15th.

When the lander entered the atmosphere, the transmission suddenly became garbled, and receivers couldn’t tell what was going on. Their worst fears were that the probe had been destroyed on impact. But, they allowed the recording tapes to keep rolling, in hopes that something could be found.

As it turns out, the probe did reach the surface of the planet, and transmitted for almost 23 minutes. It is believed that either a malfunction in the parachute system, or the high Venusian winds, caused the probe to land on it’s side. This put the transmitter antenna in a very poor position, curtailing it’s functionality. But even so, Venera 7 sent back several temperature readings of both the surface and the atmosphere.

F**K me! It actually worked!

The Russians were understandably disappointed at the mediocre performance of Venera 7, but at the same time, the information they did receive proved invaluable. Theories about the nature of Venus had been floating around the scientific community for almost a century. Venera 7 sent back hard facts about what the second planet is like. The incredible atmospheric pressure and exceedingly high temperature (an average of 885° F) was a far cry from the “wet Venus” theory that was still popular as late as 1970. Earth’s twin proved not to be a moist, pastoral land, but a hellish hothouse.

In short, Venus is not a nice place. The unforgiving and corrosive atmosphere of the second planet eventually damaged the probe, causing it to break down. Venus has developed a reputation for destroying probes in this way. Of all the probes send to Venus, both American and Russian, none have managed to last more than a couple of hours.

Venus is still an object of study because it’s a casebook example of what runaway greenhouse gases can do to a planet. The full history of Venus’s atmosphere hasn’t been settled yet, but there is evidence to suggest that it wasn’t always so heavy on carbon dioxide, and may have been more Earth-like in the distant past.

Will humans ever visit Venus? I suspect in time they will, but the nature of their visit is likely to be pure science. Science fiction writers (myself included) like to imagine a terraformed Venus serving as a home for space faring humans, but empirically speaking the likelihood of that is very small. There is evidence to suggest that Venus holds enormous mineral wealth, which could be useful for many human endeavors. But the hellish climate of Venus pretty much renders such wealth inaccessible, unless a way is found to either clean up the atmosphere, or develop robots that can operate under the extreme conditions.

If humans want to colonize another planet, Mars would be much better candidate. But the strange allure of Venus, the Evening Star, persists.

Don P. Mitchell’s website has some good information about the exploration of Venus. One of his essays, entitled Plumbing the Atmosphere of Venus, has information specific to Venera 7.