Astronomers turn eyes to New Horizons target beyond Pluto

Cosmos ^ | 11 Jul, 2017 | MICHAEL LUCY

[MtnClimber]

The New Horizons space probe, which made headlines around the world in 2015 when it beamed back humanity’s best-ever views of Pluto, is currently hurtling through the outer reaches of the solar system on its way to a rendezvous with a lump of ice known as MU69.

New Horizons won’t get to MU69 for another year and a half – the flyby is expected to occur on 31 December 2018 or 1 January 2019 – so the spacecraft is hibernating to preserve its energy.

Meanwhile, scientists on Earth are doing everything they can to find out as much as possible about MU69 before New Horizons gets there.

MU69 sits in the Kuiper belt, a broad disc of small floating bodies out beyond Neptune at distances between 30 and 50 times as far from the Sun as Earth is. In some ways it mirrors the asteroid belt that occupies a ring between the orbits of Mars and Jupiter, though Kuiper belt objects are on the whole much icier than the rocky asteroids closer to the Sun.

Very little is known about MU69: it was only discovered in 2014, when astronomers pointed the Hubble Space Telescope at the Kuiper belt to look for something interesting beyond Pluto that New Horizons might be able to manoeuvre itself towards, and because it is so tiny and distant it’s hard to get a good look.

[MtnClimber]

It is amazing that we can send radio signals that far. I bet the data rate is really low.

[Telepathic Intruder]

"...so the spacecraft is hibernating to preserve its energy."

New Horizon's power comes from the radioactive decay of plutonium. You can't stop or slow radioactive decay, so I wonder what they mean by "hibernating".

[Mr. K]

They probably have battery systems on board for the sudden total energy it needs when it is time to do some science stuff with all the instruments at once.

Then it goes to sleep and recharges them.

[BenLurkin]

NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute/Alex Parker - Article: http://astronomynow.com/2015/08/28/nasas-new-horizons-team-selects-potential-kuiper-belt-flyby-target/ Direct links to file: Medium-resolution (used in the article): http://astronomynow.com/wp-content/uploads/2015/08/nh-path_940x542.jpg High-resolution: https://planetary.s3.amazonaws.com/assets/images/9-small-bodies/2014/20141001_WithPluto_labels.png The orbit of 2014 MU69 with the path of New Horizons.

[fishtank]

They’re already WAY past Uranus!!!

[BenLurkin]

NASA Pluto probe’s next target may actually be ‘swarm’ of objects
By Mike Wall Space.com
“The fact that we accomplished the occultation observations from every planned observing site but didn’t detect the object itself likely means that either MU69 is highly reflective and smaller than some expected, or it may be a binary or even a swarm of smaller bodies left from the time when the planets in our solar system formed,”
http://www.foxnews.com/science/2017/07/07/nasa-pluto-probes-next-target-may-actually-be-swarm-objects.html

[Army Air Corps]

New Horizons has no on-board batteries, but it does have a bank of capacitors.

[Mr. K]

which are sort of like batteries, aren’t they?

[Army Air Corps]

Kinda.

[fishtank]

http://news.stanford.edu/news/2010/august/sun-082310.html

Stanford Report, August 23, 2010
The strange case of solar flares and radioactive elements
When researchers found an unusual linkage between solar flares and the inner life of radioactive elements on Earth, it touched off a scientific detective investigation that could end up protecting the lives of space-walking astronauts and maybe rewriting some of the assumptions of physics.

BY DAN STOBER

It’s a mystery that presented itself unexpectedly: The radioactive decay of some elements sitting quietly in laboratories on Earth seemed to be influenced by activities inside the sun, 93 million miles away...........

[Magnum44]

New Horizons’ uses radioisotope thermoelectric generator (RTG) as its power source, as it is way beyond being able to get enough solar energy to charge batteries. Capacitors are almost always used in power systems to condition the source, i.e. hold it at a steady level, like 28 volt for example.

[Telepathic Intruder]

Sort of what I was thinking.

[MikeD]

Hibernation for New Horizons means the science instruments are turned off, the high gain antenna is pointed toward Earth, the spacecraft computer system is put in a low power mode, and the thrusters are fired to put the spacecraft into a gentle spin. The instruments are turned off to save wear and tear on the electronics. The spin helps the spacecraft maintain course.

MD, who worked on the Alice instrument on New Horizons

[Telepathic Intruder]

Ah. Well the article said “to preserve its energy”, and you don’t know my knack for nit-picking. Spinning doesn’t help maintain its course, by the way, it helps maintain its attitude.