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69 votes

Why does it take so long to transmit an image from New Horizons to Earth?

New Horizons has just passed the Kuiper Belt Object (KBO) 2014 MU69 also known as Ultima Thule. KBOs form a belt of asteroids (the Kuiper Belt) from Neptune's orbit outwards and of which Pluto is the ...
astrosnapper's user avatar
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47 votes

Why does it take so long to transmit an image from New Horizons to Earth?

The other answer mentions it, but this gives a bit more theory as to the why. It's effectively for the same reason that your phone or Wi-Fi don't work as well and slow down when that they are far ...
The_Sympathizer's user avatar
30 votes
Accepted

The newly discovered comet NEOWISE has been given the name C/2020 F3. What is the meaning of the F3 and the C in this name?

C means "comet": it has a coma which means that volatiles are being released due to solar heating. Other possible letters are "A" for asteroid, "P" for (short) periodic ...
James K's user avatar
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29 votes
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How was Trappist-1 discovered?

The star at the center of TRAPPIST-1 is called 2MASS J23062928-0502285. It was discovered by the Two Micron All-Sky Survey (2MASS), which imaged the whole sky in the infrared between 1997 and 2001. ...
Phiteros's user avatar
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28 votes
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Why does the Earth have a z-component at the start of the J2000 epoch?

You made the same fundamental mistake that Anton Gromov made in his question on the sister Space Exploration StackExchange network site: You used the solar system barycenter rather than the Sun as the ...
David Hammen's user avatar
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19 votes

Will JWST be as durable as the hubble telescope?

Hubble was in low earth orbit, and was always intended to be serviceable. In fact, the original plan for Hubble was to have the space shuttle carry it down from orbit and take it back up, but they ...
Sean Lake's user avatar
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18 votes

How was Trappist-1 discovered?

Trappist-1 was first catalogued by the 2MASS survey about 17 years ago and has the catalogue number 2MASS J23062928-0502285. It was identified as an ultra- low-mass star with a spectral type of M7.5 ...
ProfRob's user avatar
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16 votes

Why does it take so long to transmit an image from New Horizons to Earth?

On top of the slow data transmission rate (explained in astrosnapper's answer), I think it is worth pointing out that New Horizons will enter solar conjunction next week, meaning that we won't be able ...
walen's user avatar
  • 286
15 votes

Why does it take so long to transmit an image from New Horizons to Earth?

Just to put some perspective on things: 1. New Horizons is really far away from the Earth. At the moment of closest approach, New Horizons was over 6,600,000,000 kilometers away from Earth. This is ...
ahiijny's user avatar
  • 471
10 votes
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Use MOXIE on Earth

By thermodynamics, to produce O2 and C from CO2 it will require more energy than what was delivered from producing the same quantity of CO2 by burning O2 and C1. It produces oxygen at a rate that is ...
SJuan76's user avatar
  • 216
8 votes
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What produces gravitational waves with "periods between about 100 - 8000 seconds"?

Any binary system produces gravitational waves at twice it's orbital frequency, i.e. with periods of half it's orbital period. So binary systems with periods between 200s and 16000s will produce ...
ProfRob's user avatar
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7 votes
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Did NASA/JPL get "waning" and "waxing" backwards in this video?

I think they did make a mistake. The moon waxes after a new moon and wanes before a new moon. To wax means to grow bigger or stronger (and is cognate with "waist"!). To wane means to become smaller ...
James K's user avatar
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7 votes
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Which observatories help NASA find 5 new asteroids per day?

Given that the article seems to be referring to NASA's Near Earth Object Program, it appears that there are five subprograms scanning the skies: Catalina Sky Survey (CSS) (four telescopes: 0.50 m, 0....
HDE 226868's user avatar
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7 votes

How are image credits expressed in Astronomy presentations?

There is no conventional format, really. For publications purposes if one uses data from a telescope or image or code created by someone else or similar, the source usually requests being cited or ...
MeL's user avatar
  • 111
6 votes

How was Trappist-1 discovered?

The dwarf star 2MASS J23062928-0502285 was first catalogued in 1999, if I've got that right. In May last year (2016) the Transiting Planets and Planetesimals Small Telescope–South (TRAPPIST) facility ...
GBowman's user avatar
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5 votes
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What is the coordinate acceleration for pure radial motion?

As Rob Jeffries suggested in a comment, formulating a solution for arbitrary dr/dt requires another parameter, either the energy per unit mass, E/m, or the radius of the shell where the object was ...
amateurAstro's user avatar
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5 votes
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How official is TNO 486958, 2014 MU69's new name Arrokoth?

The International Astronomical Union describes this minor planet naming process: Minor Planet Center assigns provisional designation MPC assigns permanent designation Discoverer suggests name IAU ...
Mike G's user avatar
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4 votes
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What are the most popular galaxies for which we have images?

Any such list is going to be terribly subjective. Since I'm an astronomer who studies galaxies, I'll go ahead and throw out a subjective list of the more famous, photogenic, and/or scientifically well-...
Peter Erwin's user avatar
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4 votes

What produces gravitational waves with "periods between about 100 - 8000 seconds"?

Says @uhoh “I'm curious how the strain scales with M” If $m_1$ and $m_2$ are the respective masses of an orbitally bound binary body, and we define $M_c$ as the chirp mass: $$M_c=\dfrac{(m_1 m_2)^{3/5}...
Albert's user avatar
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4 votes
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Does anybody know date of publishing of following spirit rover image in NASA apod?

It was posted on November 26, 2002, with the caption "Name This Martian Robot." There was an essay contest to name the two Mars Exploration Rovers to be launched in 2003. The winner was Sofi Collis, a ...
Mike G's user avatar
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4 votes
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How are image credits expressed in Astronomy presentations?

I'll note that the only use of "/" in your list seems to be in "ESA/Hubble", and I suspect this is supposed to mean something like "the part of ESA [European Space Agency] ...
Peter Erwin's user avatar
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4 votes

How can Voyager have left the solar system while at the same time there are solar system objects much farther?

It's a fair question! How can Voyager 1 have left the Solar System if there are comets and other trans-Neptunian objects much further away, which orbit the Sun and which therefore are part of the ...
uhoh's user avatar
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4 votes
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For how many solar system bodies do recent JPL Development Ephemerides include libration?

The short answer is, at the moment, only for the Moon. I include below a brief description of the JPL DE format to arrive to this conclusion. This link explains quite well the format of JPL DE ...
Rafa's user avatar
  • 351
4 votes
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Calculating velocity of Earth from JPL DE

It should be quite obvious that you compute the velocity of the Earth the same way you compute the position. It's multiplying a function by a constant, and that constant will be unaffected by the ...
Greg Miller's user avatar
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3 votes

How was Trappist-1 discovered?

The discovery, reported in the journal Nature, was made by astronomers using Nasa's exoplanet-hunting Spitzer Space Telescope. The telescope operates at the infrared wavelengths which glow brightest ...
Mohammad Zain Abbas's user avatar
3 votes
Accepted

Does the KBO 2014-MU69 have two numbers and entries in asteroid databases? How did it get promoted to Major Body designation?

The 3713011 object (that is the internal SPICE/SPK id) is a special trajectory computed by the New Horizons team at SwRI which included data which is not in the ...
astrosnapper's user avatar
  • 8,432
3 votes

High quality, detailed images of planets on web

The best NASA images of planets are not from the Hubble Space Telescope; they are from the spacecraft that flew by or went into orbit around them. For Uranus and Neptune, this means Voyager 2; for ...
Peter Erwin's user avatar
  • 17.2k
3 votes

Difference in Sunrise times between Horizons and NOAA

(Figured it out) The Horizons system is showing the times in UT, whereas NOAA is showing in local time. Also, Elevation of 180 degrees is not sunrise. Additionally, that first column is Apparent ...
Pradyumna's user avatar
  • 171
3 votes
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How did NASA choose "James Webb" as the name of the telescope?

I would suggest reading some articles such as this somewhat recent NPR one or this NYT one from back in 2002, when the fromer NASA administrator Sean O'Keefe made this decision. This paragraph from ...
SpaceCore's user avatar
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