“The Search for Planet 9” by Dr. Michael E. Brown
HTML-код
- Опубликовано: 25 янв 2024
- In 2006, Pluto was demoted to a “dwarf planet”. Since then, a team of planetary scientists at the California Institute of Technology (Caltech) has been searching for a hypothesized planet on the edge of the solar system. This is Planet Nine, and its search will be discussed by no other than Dr. Mike Brown, a professor of planetary astronomy at Caltech.
Dr. Michael E. Brown scans the skies searching for and intensely studying distant bodies in our solar system in the hope of gaining insight into how our planet and the planets around it came to be. In this quest, he has discovered dozens of dwarf planets (and demoted Pluto from planet to dwarf planet) and is currently hot on the trail of Planet Nine - a hypothesized body that is possibly the fifth largest planet of our solar system.
Dr. Brown has been on the faculty of the California Institute of Technology (Caltech) since 1996 and has authored more than 150 scientific papers. He has also won many awards and honors, including the Urey Prize from the American Astronomical Society’s Division of Planetary Sciences, a Presidential Early Career Award, a Sloan Fellowship, and the 2012 Kavli Prize in Astrophysics. He was inducted into the U.S. National Academy of Sciences in 2014.
Abstract: In the past 175 years, more than 30 separate astronomers have suggested the existence of a giant planet beyond Neptune. They have always been wrong. In 2016, Konstantin Batygin and I joined the list, suggesting that Planet Nine, at a distance perhaps 20 times greater than that of Neptune, is the only plausible explanation for a wide range of phenomena in the distant solar system. I’ll talk about why we think Planet Nine is real, how we are continuing to develop our hypothesis, and what we are doing to track down this elusive planet and when we might find it. Or why we, too, might be wrong
11:16 - Dr. Brown starts speaking
Awesome update on the search!
Excellent presentation
What are the reasons he mentions that it probably isn't in the perihelon where the milky way is
I think because of the effects on certain Kuiper Belt bodies …. The simulations put its orbit outside the Milky Way’s plane…
The orientation of the scattered TNOs gives an approximate orientation of the P9 orbit - with error bars ; it's probably ("probably" - with error bars! ; not "certainly") somewhere fairly close to the plane of the Solar system. Which is not the same as the plane of the galaxy.
Like all objects orbiting under Kepler's laws, it travels faster at periapse (perihelion, here) than at apoapse, which gives the "heat map" he overlaid on the orbital projection on the sky.
Why cant you use james web to look for planet 9
Answered 1:21:21
Please run the simulation for period of 3600 years (semi-major axis of 234.9 au).
Some interpretations of Sumerian text point to a civilization that came from Planet 9 (from the direction of Orion) to Earth many thousands of years ago, and they carried nuclear devices that were user for blasting asteroids on their way to Earth. If true, it would indicate that the planet was somewhere within the Kuiper Belt.
A recent publication "Is There an Earth-like Planet in the Distant Kuiper Belt?" by Patryk Sofia Lykawka and Takashi Ito (伊藤孝士)" _The Astronomical Journal, 166:118 (20pp), 2023 September_ does indicate that it is indeed most probable location of Planet 9.
I wish you could collaborate with the authors because your own publication also does nearly include the range of 234.9 au.
What about GAIA?
GAIA the pseudo-geological principle, or the astrometric satellite?
GAIA the satellite will improve the positional data for when (if) we get an orbit for P9, particularly for predicting future occultations - which will improve the orbit's accuracy fairly rapidly. But for *identifying* blips on the sky as being a P9 candidate ... much harder. On successive apparitions a putative P9 candidate could appear in a star cloud (looking like a point of light); then appear in the PSF (Point Spread Function - how accurate the sensors on GAIA are) of another star, mimicking a variable star ; then appear in a cosmic ray "blot" ... sorting out moving targets form natural variability in complex pictures is a seriously hard computational problem.
GAIA is finding hundreds (thousands?) of asteroids and TNOs each year, but may be seeing millions of them.
I haven't RTFM for GAIA, but if it's anything like KEPLER, the radio has nothing like the bandwidth to download every frame taken by the camera every minute of every day ; it'll send a digest of the data having pre-crunched the images onboard.
Remember - the computers on GAIA are state of the art - for about 10 years before launch date. It takes a considerable time for radiation-hardened versions of processors and memory chips to be manufactured and tested.
[self/R's TFM for GAIA - the Wiki version] OK - that's far enough : "Gaia targets objects brighter than magnitude 20 in a broad photometric band that covers the extended visual range between near-UV and near infrared; " At *best*, Brown's model for P9 has it's brightness about 21st magnitude. More likely 22 or 23. It's just not going to be bright enough for GAIA to see it.