New Horizons Trajectory

New Horizons Mission -History, Route, Success and Future -4- Launching to Pluto Encounter

On previous 3 articles of this New Horizons Series, we have mentioned about:

  1. New Horizons Mission – Historical Background
  2. New Horizons Mission Goals
  3. New Horizons Spacecraft

So this means we have tracked the journey of New Horizons till the launching and we are ready to take off with the spacecraft.

This articlewill mostly follow the plans of the mission stated on Article #2 from New Horizons Spacecraft launching date till the Pluto approach and preliminary preparations in 2015.

Seperate articles focus on the Pluto Flyby and Ultima Thule Flyby.

Our aim is to investigate which parts of those goals are accomplished, which plans have failed and which additional plans have been applied. While doing this, we will follow New Horizons Mission timeline till the Pluto encounter.

Are you ready for a meteoric journey?
We will start the countdown for the fastest rocket launching in the history!

New Horizons Spacecraft Launching
11..10..9..8..7..6..5..4..3..2..1. Lift off! Image Credit: JHUAPL-NASA

New Horizons Mission – Launching

As mentioned on Article #2, the schedule for the New Horizons launching had deadlines. Daily launching periods were limited with 2 hours per day. In addition, the optimum launching date were between 11 and 27 January 2006 for earliest Pluto flyby.

Due to unpredicted delays, New Horizons’ launching rocket could be moved to the launching pad on 16 January 2006.

On 17 January 2006 all was set and launching was to be attempted. However, the operation had to be postponed for one more day due to heavy wind .

And during the attempt on next day, there was another unfortunate incident: A blackout in Mission Operation Center – JHUAPL. There were only 9 more days and within those 9 days, only 18 hours more for a successful launching. Time was running out!

Luckily on 19 January 2006 at 14:00 LT (19:00 UTC), New Horizons Spacecraft was successfully launched aboard the Atlas V 551 (AV-010) from Launch Complex 41 of Cape Canaveral Air Force Station in Florida.

Here is how New Horizons Probe rises in the sky inside the Atlas rocket. Credit: NASA/Lockheed Martin

New Horizons Mission – From Launching to Jupiter Encounter

If the deadline 27 January was slipped through the fingers, that was going to lower the scientific expectations and would be a big depression for the New Horizons Team. Thankfully that did not happen!

A well-done launching of New Horizons Spacecraft was achieved, and the spacecraft was on the way to its primary target Jupiter both for pre-Pluto scientific preparations and a gravity bounce.

As planned earlier, the spacecraft was released by the rocket with a speed more than 58.000 km/h (58.536km/h) which was the highest launching speed of all times. In less than an hour, the seperation was completed and New Horizons Spacecraft was all alone for its decades of journey.

Following the launching, the spacecraft was immediately waken up and its route was calculated. After 9 hours, the spacecraft was already ahead of Moon‘s orbit. And within 24 hours, the actions were taken to reduce the spin rate of New Horizons Spacecraft and power on most of the scientific payload.

New Horizons Scientific Payload
All science instruments of New Horizons Spacecraft. Source: JHUAPL

Thrusters of the probe were ran on 28 January, 30 January and 9 March for corrective action. The launching direction of the Atlas rocket was so accurate that the corrective action required only 1/10 of what was estimated in terms of fuel.

From mid February till second week of March, electrical tests of all scientific equipments were completed.

Only 11 weeks after the launching, New Horizons Spacecraft outran the Mars orbit.

In Asteroid Belt – A Surprising Visit

During the long way to Jupiter, preoccupations for the spacecraft would keep it busy in the Asteroid Belt. While the mission and the probe were running, New Horizons Team caught a good opportunity for an initial test: A glance to the asteroid 132524 APL.

132524 APL Asteroid
132524 APL imaged by New Horizons Spacecraft’s Ralph from 1.3 million kilometers. Credit: NASA/JHUAPL/SWRI, Image source here

The closest encounter with 2.5 kilometers wide asteroid 132524 APL took place on 13 June 2006 from 101.867 kilometers away. This encounter was an unplanned, initial and encouraging chance for planning future flybies and playing with some toys for both scientific and navigational purposes.

On 24 August 2006, International Astronomical Union (IAU) announced a new set of requirements for being a planet and demoted Pluto from an ordinary planet to a dwarf planet. Pluto was not a planet aymore!

On 29 August 2006, cover of the only remaining inactive scientific device LORRI (Long Range Reconnaissance Imager) was opened for the first time. Its first image was from the Messier 7 Star Cluster.

Messier 7 Cluster
Center of Messier 7 Star Cluster as seen by New Horizons – LORRI. Source here, Credit: NASA/JHUAPL/SWRI

LORRI was targeted to Jupiter for the first time for initial images on 4 September 2006 from a distance of 291 million kilometers. Hence the planned Jupiter System studies and the pre-planned instrumental condition checks were initiated.

Jupiter as seen by New Horizons
First Jupiter image by LORRI of New Horizons Spacecraft. Shadows of Europa (on left) and Io (on right) are also visible. Source here, Credit: NASA/JHUAPL/SWRI

On 28 November 2006, New Horizons’ LORRI captured Pluto for the first time. Below series of images were taken from 4.2billion kilometers away from Pluto.

Pluto Image
Say hello to Pluto! Source here, Credit: NASA/JHUAPL/SWRI

New Horizons Mission – Jupiter Encounter and Studies

For speeding up the spacecraft, the gas giant Jupiter was planned to be used. And as mentioned earlier for seizing this opportunity, a detailed scientific study was planned on Jupiter System.

That was a great chance for worldwide researchers as well: It was going to be the first close-by analysis of Jupiter System after the Galileo Spacecraft‘s visit in 2003 and the cameras of New Horizons were remarkably advanced comparing to Galileo’s.

Although the instruments onboard the probe started to capture Jupiter in last quarter of 2006, detailed images and studies of Jupiter System were initiated after new year as New Horizons Space Probe caught up with.

Major Jupiter System moments of New Horizons Mission are listed as follows:

Initiation of New Horizons’ Jupiter encounter is considered to begin with the image of Jupiter together with moon Io on 8 January 2007 from 81 million kilometers away.

On 10 February 2007, a more detailed photo of Jupiter was taken. During the shot, the probe was only 29 million kilometers away from Jupiter and it was the last chance to have a full view of the giant.

Jupiter Image
Jupiter, as seen by New Horizons Spacecraft. Details as wide as 290km are visible. Source here, Credit: NASA/JHUAPL/SWRI

Jupiter Moons Targeted

As the spacecraft came closer and closer, more details of the planet and its moons were becoming visible.

On 26 February 2007, New Horizons Spacecraft captured Io from 4 million kilometers proximity while a huge volcanic dust was swelling over its surface.

Io Moon Volcanic Dust
Moon Io and the volcanic plume over it. Source here, Credit: NASA/JHUAPL/SWRI

The plume was 240 kilometers high all over the Tvashtar Volcano, which was previously detected and captured several times. Right after the imaging, John Spencer, team leader of New Horizons Jupiter Encounter Science Team said “This is the best image of a large volcanic plume on Io since the Voyager flybys in 1979“.

Next day (27 February 2007), two more Jupiter moons: Europa and Ganymede were captured.

New Horizons took a photo of Europa 3.1 million kilometers away from it, with details 15 kilometers/pixel visible.

Jupiter Moon Europa
Jupiter’s bright moon Europa via New Horizons Spacecraft. Source here, Credit: NASA/JHUAPL/SWRI

Few hours later, Ganymede‘s best image was shot from 3.5 million kilometers to moon surface; as detailed as 17 kilometers/pixel. Picture of the largest moon in our Solar System was downlinked to Earth on same day.

Jupiter moon Ganymede
New Horizons Ganymede image. Source here, Credit: NASA/JHUAPL/SWRI

The last Galilean Satellite Callisto was also captured by New Horizons cameras on 27 and 28 February 2007. Since the moon was located behind Jupiter during the closest approach, those images were captured from 4.7 and 4.2 million kilometers away from the moon.

Jupiter Moon Callisto
Callisto captured on 27 (on left) and 28 February 2007. Source here, Credit: NASA/JHUAPL/SWRI

New Horizons Mission Jupiter Studies

28 February 2007 (UTC) has another importance: That’s the date when closest Jupiter flyby of the New Horizons Space Probe takes place! This move boosted the probe’s speed around 14.000 km/h and reduced the time to reach Pluto for about 3 years.

Before and after the closest Jupiter approach, New Horizons Spacecraft studied the Jupiter System approximately 6 months. During this period, the major scientific goal on Jupiter System studies was examination of Jupiter atmosphere, weather, rings and moons.
Here is a brief list of New Horizons Jupiter flyby studies:

The biggest lesson learned from Galileo (2003) to New Horizons (2007) was: “That’s not the same Jupiter System anymore“!

The huge storm activities of Jupiter were analyzed and the systematic changes over years were calculated.

The Little Red Spot of Jupiter (having 70% of Earth‘s diameter) was formed around years 1998-2000. New Horizons was the first probe to image this feature at Jupiter’s foot. Invaluable information about this spot was collected.

Little Red Spot on Jupiter
Not the magic ball: This is the little red spot on Jupiter as captured by New Horizons Spacecraft. Details down to 15 kilometers are available. Source here, Credit: NASA/JHUAPL/SWRI

Ring system of Jupiter was broadly imaged by New Horizons cameras. Although signs of young residues of collisions were explored, no additional moons could be discovered.

Particle analysis of Jupiter’s magnetosphere performed and signs of eruption of material from Io surface were spotted.

New Horizons Mission Jupiter Moons Studies

All Galileo Moons were in challenging positions during the Jupiter flyby.
Despite this handicap, the enhanced cameras of New Horizons Spacecraft took spectecular photos of all 4 moons.

Because of its similarity to Pluto and Charon, Callisto’s surface was examined as a rehearsal of pre-Pluto encounter studies.

The next moon with scientific importance was the volcanic and helpless moon of Jupiter: “Io”. 36pcs volcanoes on Io were spotted. Lava temperatures were examined and found to be close to the ones’ on Earth.

Eclipse on Io
On this fantastic shot, Jupiter completely blocks the sunlight by standing in between Sun and Io. So what might possibly be glowing during an eclipse? Its the lava and the magnetic interaction with Jupiter! Source here, Credit: NASA/JHUAPL/SWRI

As stated above, Tvashtar Volcano was active while New Horizons was looking and the plumes raised up to 330 kilometers high.
In addition, the surface was checked, compared with Galileo maps from 1999 and this served a great opportunity to analyse re-surfacing effects of the volcanic activities.

In addition to above, the mission observed some of the smaller moons for fine-tuning their orbit calculations.

The last but not the least, by comparing with Galileo Spacecraft data; the scientific instruments of New Horizons were tested “on field” and verified to be working properly. In that perspective, New Horizons Mission was a unique one: The only interplanetary mission to successfully perform an extensive self-check before its primary targets.

Moon Io with a volcanic plume
A giant mountain of volcanic dust over Io. Now look to 9 o’clock direction: There’s an other, smaller one! At one glance you can easily see how Jupiter agonizes Io. Source here, Credit: NASA/JHUAPL/SWRI

Jupiter Data Downlinking and “An Issue”

After the closest encounter with Jupiter on 28 February 2007, downlinking of the collected data was initiated. However on 19 March 2007 there was a setback: Multiple bits were “flipped” on the primary CDH processor of the spacecraft and it was trying to re-boot itself all the time. Eventually this led to a pre-programmed safe mode for the spacecraft.

That safe mode resulted with a “lost contact” for 1.5 hours however the data transmission was initiated shortly after. Thanks to the autonomous work of the CDH and the ground teams’ interventions, normal operation mode was sustained within 2 days.

On 26 March 2007, mission PI Alarn Stern reported: “What actually caused the spacecraft C&DH memory to be corrupted with a two-bit error in a single C&DH address? We’re still trying to determine that, but early indications are it was related to a burst of four bit errors within a short time that may have been due to RTG or natural space-environment radiation“.

Alan Stern
Alan Stern, Principal Investigator of New Horizons Mission. Source here, Credit: Paul Fetters

Example is better than precept! The team experienced the problem on-hands and they knew how to react for the next time.

Above setback unfortunately obstructed some of the experiments on Jupiter’s magnetosphere and slightly delayed downlinking of all Jupiter data within the planned time. However, there was a huge time till the Pluto encounter: 8 big years!
All data gathered from Jupiter System was successfully downlinked to NASA’s Deep Space Network till June 2017.

New Horizons Mission – The Hibernation Mode

Upon completion of Jupiter data transfer, it was time to switch the spacecraft into the pre-planned hibernation mode. On 28 June 2007, the initial hibernation mode was started. During the hibernation mode, most of the systems together with the scientific payload dropped asleep in regular basis and responses of the instruments were observed.

Hibernation Mode: 2007 to 2011

For all hibernation mode periods, 10 weeks of initiation tests were planned. On 20 August 2007, the first hibernation mode tests were completed successfully and the active hibernation mode was started.

Source here, Credit: NASA/Fred Sayers

On 25 September 2007, another trajectory correction maneuver was performed and a half-awake, long journey for the spacecraft was on the way.

The years between 2008 and 2012 were respectively quiet for New Horizons Team: On 8 June 2008, the probe crossed the Saturn orbit. On 16 December 2008 and 27 August 2009, second and hibernation mode periods were initiated. On 29 December 2009, the spacecraft was already closer to Pluto than Earth.

In June 2010, LORRI was directed to different targets back and forth: It captured some images from Jupiter and its big moons, planet Neptune and to Messier 7 Star Cluster for calibration purposes. Following those calibrations, a minor trajectory correction was applied on 30 June 2010.

Neptune captured by New Horizons
Neptune imaged by LORRI from 2.15 billion kilometers away. Source here, Credit: NASA/JHUAPL/SWRI

Hibernation Mode: 2011 to 2015

On 18 March 2011, the probe was ahead of Uranus orbit. On 28 June 2011 and 26 June 2012, two seperate and exciting news were heard: Two more Pluto moons were discovered, which were later named Kerberos and Styx. Although those tiny moons were going to add more fun to the Pluto System studies, that caused a new concern: Possible debris around. However the team worked on this and calculated the chance to hit to a debris which was less than 1%.

In July 2012, the team decided to wake some of the instruments up for detailed analysis of the heliosphere. Those data were gathered by the team in January 2013 and at the same time minor software corrections were transmitted to the spacecraft.

On 1 July 2013, New Horizons’ LORRI was able to image Charon seperately for the first time.

Charon moon
The bright object here is Pluto. Charon is located at 11 o’clock position. Credit: NASA/JHUAPL/SWRI

On 14 July 2014, another trajectory correction was performed and few days later, more images of Pluto and Charon were captured.. And on 25 August 2014, the last planet on the road: Neptune‘s orbit was behind. And 4 days after on 29 August 2014, the fourth and the last hibernation period before Pluto approach was initiated.

Finally on 6 December 2014, the probe was nudged for a wake up: It was time for Pluto and Pluto facts!

Our next articles in series will include details about the rest of the journey: Pluto approach, scientific results of the Pluto encounter. And the next one will track the Kuiper Belt journey of New Horizons Spacecraft including the Ultima Thule approach.

Stay tuned!

References

  • We aim to build a proper Pluto encyclopedia and your contributions are highly appreciated!
  • Any deficiencies on this article? Please type to below comment box or contact us from this link. We are ready to check and clarify.

One Response

  1. Laurel E. Kornfeld September 28, 2019

Leave a Reply