APOD: Interstellar Interloper 2I/Borisov (2019 Oct 18)

Comments and questions about the APOD on the main view screen.
User avatar
APOD Robot
Otto Posterman
Posts: 3921
Joined: Fri Dec 04, 2009 3:27 am

APOD: Interstellar Interloper 2I/Borisov (2019 Oct 18)

Post by APOD Robot » Fri Oct 18, 2019 4:05 am

Image Interstellar Interloper 2I/Borisov

Explanation: After the 2017 detecton of 1I/'Oumuamua, comet 2I/Borisov has become the second recognized interstellar interloper. Like 'Oumuamua, Borisov's measured hyperbolic trajectory and speed as it falls toward the Sun confirm that its origin is from beyond our Solar System. But while detailed observations indicate 'Oumuamua is a rocky body with differences from known Solar System objects, Borisov is definitely a far wandering comet. Taken on October 12, 2019 this Hubble Space Telescope image of Borisov reveals a familiar looking comet-like activity and concentration of dust around around its nucleus. Not resolved in the image, some estimates suggest the nucleus could be between 2 and 16 kilometers in diameter. At the time of the Hubble image, comet 2I/Borisov was about 418 million kilometers away. Borisov is still inbound though and will make its closest approach to the Sun on December 7 at a distance of about 300 million kilometers (2 Astronomical units).

<< Previous APOD This Day in APOD Next APOD >>

Don Bruns

Re: APOD: Interstellar Interloper 2I/Borisov (2019 Oct 18)

Post by Don Bruns » Fri Oct 18, 2019 4:18 am

The aliens are onto us. After we figured out where Oumuamua came from, they added a dust and gas envelope to hide their secret. :D

daddyo
Ensign
Posts: 74
Joined: Tue Feb 10, 2015 4:48 am

Re: APOD: Interstellar Interloper 2I/Borisov (2019 Oct 18)

Post by daddyo » Fri Oct 18, 2019 5:17 am

Wondering if the speckled coma appearance is an artifact of the imager itself, or actually comes from particles.

TheOtherBruce
Ensign
Posts: 92
Joined: Wed Jul 17, 2019 6:07 pm

Re: APOD: Interstellar Interloper 2I/Borisov (2019 Oct 18)

Post by TheOtherBruce » Fri Oct 18, 2019 7:34 am

Something I suspected when I saw the perihelion distance of 2AU — the hyperbolic orbit (there are diagrams on the Wikipedia page) is very open and flat. I'd guesstimate it's going to be deflected only about 30° or so as it passes the sun; definitely going at a considerable rate of knots, even faster than ʻOumuamua.

Has anyone seen any estimated maximum brightness figures? I don't see anything on the Wiki page.
This universe shipped by weight, not by volume.
Some expansion of the contents may have occurred during shipment.

User avatar
bystander
Apathetic Retiree
Posts: 19740
Joined: Mon Aug 28, 2006 2:06 pm
Location: Oklahoma

Re: APOD: Interstellar Interloper 2I/Borisov (2019 Oct 18)

Post by bystander » Fri Oct 18, 2019 9:18 am

Know the quiet place within your heart and touch the rainbow of possibility; be
alive to the gentle breeze of communication, and please stop being such a jerk.
— Garrison Keillor

Boomer12k
:---[===] *
Posts: 2663
Joined: Sun Apr 22, 2007 12:07 am

Re: APOD: Interstellar Interloper 2I/Borisov (2019 Oct 18)

Post by Boomer12k » Fri Oct 18, 2019 10:12 am

A friend and I were discussing this the other day...I did not know there had been an earlier one... very interesting...

:---[===] *

User avatar
orin stepanek
Plutopian
Posts: 5431
Joined: Wed Jul 27, 2005 3:41 pm
Location: Nebraska

Re: APOD: Interstellar Interloper 2I/Borisov (2019 Oct 18)

Post by orin stepanek » Fri Oct 18, 2019 11:56 am

My guess is that when you have a Nova; there is probably debri that interlopes! :mrgreen:
Orin

Smile today; tomorrow's another day!

User avatar
Chris Peterson
Abominable Snowman
Posts: 14996
Joined: Wed Jan 31, 2007 11:13 pm
Location: Guffey, Colorado, USA

Re: APOD: Interstellar Interloper 2I/Borisov (2019 Oct 18)

Post by Chris Peterson » Fri Oct 18, 2019 1:47 pm

daddyo wrote:
Fri Oct 18, 2019 5:17 am
Wondering if the speckled coma appearance is an artifact of the imager itself, or actually comes from particles.
It's just noise. A longer exposure would appear smoother. A long enough exposure and it would be perfectly smooth at the level of our visual perception. This is gas more than dust, but even for the dust the particle size and spacing is far below the resolution of the optics or the imaging device.
Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

Joe2579

Re: APOD: Interstellar Interloper 2I/Borisov (2019 Oct 18)

Post by Joe2579 » Fri Oct 18, 2019 4:54 pm

Could we, i.e. our solar system, be entering a radial section of the galactic rotation disc, that has large asteroids doing static polar orbits (as opposed to equatorial orbits that orbit with the galactic rotation), and as such are coming into the galactic radial section during which, on one of our orbits, an asteroid ended the dinosaurs ! There would need to be several places around the 250 Million year galactic rotation orbit where these polar orbit asteroids intersect, in order for 65 Million years ago to have intersected one, as we are possibly now about to do so again !!

User avatar
Chris Peterson
Abominable Snowman
Posts: 14996
Joined: Wed Jan 31, 2007 11:13 pm
Location: Guffey, Colorado, USA

Re: APOD: Interstellar Interloper 2I/Borisov (2019 Oct 18)

Post by Chris Peterson » Fri Oct 18, 2019 5:12 pm

Joe2579 wrote:
Fri Oct 18, 2019 4:54 pm
Could we, i.e. our solar system, be entering a radial section of the galactic rotation disc, that has large asteroids doing static polar orbits (as opposed to equatorial orbits that orbit with the galactic rotation), and as such are coming into the galactic radial section during which, on one of our orbits, an asteroid ended the dinosaurs ! There would need to be several places around the 250 Million year galactic rotation orbit where these polar orbit asteroids intersect, in order for 65 Million years ago to have intersected one, as we are possibly now about to do so again !!
There's really no need to invoke interstellar bodies when considering impacts with planets. There are vastly more bodies within our own solar system that can become planetary impactors, and an impact from a solar system body is billions of times more likely than an impact from the occasional interstellar visitor.
Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

TheOtherBruce
Ensign
Posts: 92
Joined: Wed Jul 17, 2019 6:07 pm

Re: APOD: Interstellar Interloper 2I/Borisov (2019 Oct 18)

Post by TheOtherBruce » Fri Oct 18, 2019 5:39 pm

Chris Peterson wrote:
Fri Oct 18, 2019 5:12 pm
There's really no need to invoke interstellar bodies when considering impacts with planets. There are vastly more bodies within our own solar system that can become planetary impactors, and an impact from a solar system body is billions of times more likely than an impact from the occasional interstellar visitor.
Agreed, but I think we need to get a better handle on "occasional". Remember the estimates that were developed after the discovery of ʻOumuamua — there are likely thousands of interstellar objects passing through the solar system at any given time, most likely coming from completely random directions. It's that randomness and their small size that's let them escape notice until now.
This universe shipped by weight, not by volume.
Some expansion of the contents may have occurred during shipment.

User avatar
Chris Peterson
Abominable Snowman
Posts: 14996
Joined: Wed Jan 31, 2007 11:13 pm
Location: Guffey, Colorado, USA

Re: APOD: Interstellar Interloper 2I/Borisov (2019 Oct 18)

Post by Chris Peterson » Fri Oct 18, 2019 5:48 pm

TheOtherBruce wrote:
Fri Oct 18, 2019 5:39 pm
Chris Peterson wrote:
Fri Oct 18, 2019 5:12 pm
There's really no need to invoke interstellar bodies when considering impacts with planets. There are vastly more bodies within our own solar system that can become planetary impactors, and an impact from a solar system body is billions of times more likely than an impact from the occasional interstellar visitor.
Agreed, but I think we need to get a better handle on "occasional". Remember the estimates that were developed after the discovery of ʻOumuamua — there are likely thousands of interstellar objects passing through the solar system at any given time, most likely coming from completely random directions. It's that randomness and their small size that's let them escape notice until now.
Yes, but we observe tens of thousands (millions if we include meteoroids) of Solar System bodies for every interstellar body. It isn't randomness that has caused them to escape notice, it is rarity. We miss most Solar System bodies which are not in short period closed orbits, as well. Technology is allowing us to catch more rare objects... both local and interstellar. The ratio of the two isn't likely to change.
Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

Amos

Re: APOD: Interstellar Interloper 2I/Borisov (2019 Oct 18)

Post by Amos » Fri Oct 18, 2019 7:42 pm

Will someone kindly explain the coordinate system in use represented within this image? Or for that matter the actual meaning of any of the supplemental information included within the image, the only parts of it explained seem to be the name of the comet and the date the image was taken. Apologies if I'm coming across as obtuse but I'm just genuinely curious and don't recall seeing these elements explained over the past few years of browsing apod.

User avatar
Chris Peterson
Abominable Snowman
Posts: 14996
Joined: Wed Jan 31, 2007 11:13 pm
Location: Guffey, Colorado, USA

Re: APOD: Interstellar Interloper 2I/Borisov (2019 Oct 18)

Post by Chris Peterson » Fri Oct 18, 2019 7:57 pm

Amos wrote:
Fri Oct 18, 2019 7:42 pm
Will someone kindly explain the coordinate system in use represented within this image? Or for that matter the actual meaning of any of the supplemental information included within the image, the only parts of it explained seem to be the name of the comet and the date the image was taken. Apologies if I'm coming across as obtuse but I'm just genuinely curious and don't recall seeing these elements explained over the past few years of browsing apod.
The "N" arrow represents the declination axis, and points towards the north pole. The "E" arrow represents the right ascension axis, and points eastward. Declination on the sky is analogous to latitude and right ascension is analogous to longitude. The reason east is to the left, and not the right as we are accustomed to on terrestrial maps, is because we're looking at the inside of the celestial sphere, as opposed to the outside of the terrestrial one.

If you were to travel in a straight line in this coordinate system (that is, a straight line drawn on a sphere) in the direction of the "Sun" arrow, at the time the image was taken, you'd intersect the Sun, which explains the asymmetry of the coma.
Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com