Welcome to DU!
The truly grassroots left-of-center political community where regular people, not algorithms, drive the discussions and set the standards.
Join the community:
Create a free account
Support DU (and get rid of ads!):
Become a Star Member
Latest Breaking News
General Discussion
The DU Lounge
All Forums
Issue Forums
Culture Forums
Alliance Forums
Region Forums
Support Forums
Help & Search
Science
Related: About this forumPluto: Preparing for the Perfect Alignment (earthsky.org) {CORRECTED}
Last edited Wed Jul 4, 2018, 11:31 AM - Edit history (1)
By EarthSky Voices in Human World | Space | July 3, 2018
On July 12, 2018, Earth will cross the suns face, seen from Pluto. Doing so requires a near-perfect alignment that hasnt happened since 1931, around the time of Plutos discovery. Astronomer Anne Verbiscer explains why, around this event, earthly telescopes will be aimed Plutos way.
This article by astronomer Anne Verbiscer at the University of Virginia was originally published by NASAs Pluto New Horizons website. Reprinted here with permission. {links to older page}
Every year, planets orbiting the sun beyond Earths orbit reach what astronomers call opposition, when they appear in the sky at the position opposite that of the sun. At opposition, the planet, satellite or asteroid and the sun line up with Earth between them. Pluto and its moons will be at opposition in 2018 on July 12 at 09:42 UTC; translate UTC to your time. Sometimes these alignments are so precise that if you were standing on the surface of one of these bodies and looking back at Earth, you would see our planet transit (or move across) the solar disk.
These special oppositions take place when the planet is near what is called the line of nodes. The line of nodes is the intersection of the plane of the Earths orbit and a planets orbit. Look back at the image above. The line of nodes is the intersection between the orbital plane of Pluto (purple) and that of Earth (white). Because Plutos orbit is significantly inclined relative to the ecliptic plane, node crossings are rare, and because Plutos orbit is eccentric, they occur in 87- and 161-year intervals.
If the planet is near one of these intersection points at the time of its yearly opposition, it is in near-perfect alignment with the Earth and sun. Such is the case in 2018.
Pluto was last near one of these intersection points in 1931. On July 12, 2018, as seen from Pluto, Earth will cross the suns face. It will not be a central transit, but it will be a transit nonetheless.
***
more: http://earthsky.org/space/pluto-july-12-2018-opposition-nodes-earth-transit
InfoView thread info, including edit history
TrashPut this thread in your Trash Can (My DU » Trash Can)
BookmarkAdd this thread to your Bookmarks (My DU » Bookmarks)
3 replies, 917 views
ShareGet links to this post and/or share on social media
AlertAlert this post for a rule violation
PowersThere are no powers you can use on this post
EditCannot edit other people's posts
ReplyReply to this post
EditCannot edit other people's posts
Rec (2)
ReplyReply to this post
3 replies
= new reply since forum marked as read
Highlight:
NoneDon't highlight anything
5 newestHighlight 5 most recent replies
Pluto: Preparing for the Perfect Alignment (earthsky.org) {CORRECTED} (Original Post)
eppur_se_muova
Jul 2018
OP
Thanks for catching this -- I tried to post from the original source, messed it up.
eppur_se_muova
Jul 2018
#2
Princess Turandot
(4,787 posts)1. This is from 2016; you might want to add '2016' to the title...
...especially since the article references 'July 8' as being in the past.
BTW, New Horizon's next planetoid rendezvous is coming up fast: it's on track for its Kuiper belt object reconnaissance on New Years Day!
eppur_se_muova
(36,261 posts)2. Thanks for catching this -- I tried to post from the original source, messed it up.
The article originally posted is linked in the new post -- apparently it was intended for background info.
Judi Lynn
(160,526 posts)3. This image at the link is amazing, as well:
When the Earth and moon transit the sun, seen from an outer planet, they might
be seen as dark dots crossing the suns face. On July 12, 2018, though, an
observer on Pluto would need special equipment to detect the transit, because
at Plutos average distance of 3.67 billion miles (about 6 billion km) the sun
appears only marginally larger than Jupiter does from Earth. Image via P. Molaro,
et al., from arXiv 1509.01136, 2015/NASA New Horizons blog.
Thank you for the information.