Finding Pluto is really New Horizon’s biggest problem
As New Horizons speeds towards its planned fly-by of Pluto on July 14, the biggest problem faced by its engineers is making sure the spacecraft actually finds and photographs the planet.
Because astronomers discovered the dwarf planet in 1930, they have seen only part of its 248-year path around the Sun, and they don’t know exactly where Pluto is. And New Horizons is so far from Earth that it takes 9 hours to send and receive a signal, making the spacecraft hard to direct in real time. “Everything is pushed to the extreme,” says Bobby Williams, an engineer at KinetX Aerospace in Simi Valley, California, who heads the mission’s navigation team.
This fact, which has not been mentioned previously as far as I remember, suggests that there is a good chance that New Horizons might fly through its planned window and aim its cameras at the wrong spot in the sky, missing Pluto entirely. It also explains partly why the images released so far have been so fuzzy: They are focused mostly on doing navigation work, and are taking wide angle shots to make sure they catch Pluto in their picture frame. Zooming in too close might actually miss Pluto as they don’t exactly know where it is.
All this only makes the July 14th fly-by even more exciting. Let us hope they do due diligence and get the pictures we all want!
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
As New Horizons speeds towards its planned fly-by of Pluto on July 14, the biggest problem faced by its engineers is making sure the spacecraft actually finds and photographs the planet.
Because astronomers discovered the dwarf planet in 1930, they have seen only part of its 248-year path around the Sun, and they don’t know exactly where Pluto is. And New Horizons is so far from Earth that it takes 9 hours to send and receive a signal, making the spacecraft hard to direct in real time. “Everything is pushed to the extreme,” says Bobby Williams, an engineer at KinetX Aerospace in Simi Valley, California, who heads the mission’s navigation team.
This fact, which has not been mentioned previously as far as I remember, suggests that there is a good chance that New Horizons might fly through its planned window and aim its cameras at the wrong spot in the sky, missing Pluto entirely. It also explains partly why the images released so far have been so fuzzy: They are focused mostly on doing navigation work, and are taking wide angle shots to make sure they catch Pluto in their picture frame. Zooming in too close might actually miss Pluto as they don’t exactly know where it is.
All this only makes the July 14th fly-by even more exciting. Let us hope they do due diligence and get the pictures we all want!
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
Bob, I have been a little surprised by how fuzzy the images so far have been but your explanation must explain it. Do you have any idea what the aperture is of their main camera? A relatively small telescope can get a clearer image of Mars at similar distances and our telescopes have to contend with the earth’s atmosphere.
Apparently my fingernails weren’t bitten down quite enough yet.
Is there evidence of massive objects in the kuiper belt, or beyond, causing perturbations in Pluto’s orbit?
No. The reason they do not know Pluto’s exact position is simply because its 248 year orbit has only been tracked for less than 80 years. We simply don’t have enough information yet to precisely plot out the orbit. We can make some very good estimates, and every minute that New Horizons gets closer to Pluto those estimates improve, but they are still nonetheless estimates.
Note that we are not talking about gigantic errors. The problem is that to point New Horizons precisely, at the speed it will be traveling as it flies past Pluto, requires a level of precision that we simply might not yet have.
Perhaps now is the time to start taking progressively narrower field-of-view so that a more precise location can be determined and they can more accurately point the camera at closest approach?
Up to last week, all pluto imaging came from OpNav Campaigns that LORRI was used for. I would hope that the KinetX team that actually controlls the probe’s trajectory has a solid backroom of engineers, or can reach out to other outsourced teams that serve NASA. If that is wishful thinking on my part, maybe JPL could be pulled in to tap their vast knowledge (New Horizons is ran by APL not JPL) ?