Considering how long telescopes have been around and the limitations imposed by our atmosphere, it boggles the mind to think there are new discoveries – lots of new discoveries, from Earth based telescopes.
The planet is a typical member of the Kuiper belt, but its sheer size in relation to the nine planets already known means that it can only be classified as a planet, Brown says. Currently about 97 astronomical units from the sun (an astronomical unit is the distance between the sun and Earth), the planet becomes the farthest-known object in the solar system, and the third brightest of the Kuiper belt objects.
“It will be visible over the next six months and is currently almost directly overhead in the early-morning eastern sky, in the constellation Cetus,” says Brown, who made the discovery with colleagues Chad Trujillo, of the Gemini Observatory, and David Rabinowitz, of Yale University, on January 8.
Yale – wow! That means some of these discoveries are being made by people who work down the block from me. I decided to drop David Rabinowitz a congratulatory note.
Before we go on – I am not shy about using email to reach out, especially when there’s more information I want. I have corresponded with Nobel Prize winners, famous scientists and journalists, producers I’ve wanted to work for… even actor/lawyer/game show host/commentator Ben Stein¹.
I just want you to know, every time I read about this amazing discovery, I am pleased to see there was a New Haven/Yale connection. Congratulations on your work.
When things calm down and you get a few minutes, could you tell me how this evaded detection for so long? I would have assumed there would be some gravitational component that was seen yet unaccounted for and would have led to an earlier search. Of course my knowledge of planetary physics leaves lots to be desired.
All the best,
A few hours later, there was a reply.
It is amazing that this new planet, which I am still getting used to calling a planet, was not detected before. But it doesn’t have anything to do with the orbital dynamics. It is too small to have an effect on the orbits of the other planets. So it wouldn’t show up that way.
Really, the short answer is that nobody ever looked before. For the first time, we are using a large telescope and a large digital camera to search the whole northern hemisphere for distant planets. Building the camera was a major accomplishment – it was a team effort at the Yale Physics Dept and Indiana Univ. in Bloomginton IN. Called the Palomar-Quest camera, it is one of the worlds largest digital camera – 160 Megs. In combination with the special wide-field optics of the 48″” Samuel Oschin Schmidt at Palomar Observatory, we can search the whole northern hemisphere more efficiently than anybody else.
Now nobody ever though it would be very productive to search for distant planets far from the plane of the planets — the ecliptic plane. Our competitors, in fact, mostly search only within a few degrees of the ecliptic. But because we can search so much area with Palomar-Quest, we decided to search everywhere. We started at the ecliptic, believing this would be most productive. But strangely, the most intriguing discoveries have been out of the plane. We found Sedna 12 degrees below the plane, we found our new planet 14 deg below the plane. One of the new objects reported on Friday, called 2003 FY9, is the brightest (but not biggest) object in the Kuiper Belt. It is 30 degrees above the ecliptic plane.
What makes astronomy so exciting, there is so much out there left to be discovered. Building a new instruments helps. But just looking where nobody expects to find something, you can get lucky. We still have more area to search even farther from the ecliptic. So there could even be more exciting things to find.
Basically, the team took a succession of photos and then analyzed them for movement. From our perspective, distant stars stand still while much closer planets (or asteroids, comets and meteors) move in the sky. Look for something moving like a planet and you just might spot a planet! Or, you might just be picking out some noise in the telescope’s sensors. That’s where astronomers come in.
The picture on the left represents what you would see, looking at the Sun from this distant planet. It’s just another very bright star in a very dark sky.
To me, the “magic keys” to this discovery are both the laser guide star adaptive optics, which allows astronomers on the ground to take images as sharp as the images from the Hubble Space Telescope and the ability to have much of the grunt work of comparing images done by computer.
In any event, as more and more objects are discovered, there will be more and more controversy over what exactly is a planet? Lots of astronomers don’t think Pluto is a planet! And this new sighting, though larger than Pluto, is in some ways similar – especially its orbit.
In the meantime, the word is the discoverers are waiting for approval to call this planet, “Xena.”
¹ – After the “Deep Throat” unmasking, I wrote Ben to disagree with a commentary he had written. We went back through three or four sets of emails, airing our opposing views. I enjoyed the discussion, and was meticulous in sourcing my conclusions. Ben also seemed to enjoy the ‘fight’ and gave back without hesitation.
Though we disagreed strongly, I have a great deal of respect for him and was more than a little pleased he was willing to engage me in this manner.